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Tigercat
20-04-2021, 06:54 PM
I'm new here as a found some ggle links that suggest I may find some knowledgeable's that may provide me with some assistance. I have searched; YT + ggle + fixya +......++++. I have been at this for days and I'm at my wits end to find a (any/reliable) solution.
The (indoor) AC is as noted. The fan/blower motor bearings are knacked and I wish to remove the motor and replace the bearings (yep can be done) - new motor ~$200 (& $450+ labour), new bearings ~ $20-30. Plus the motor is a squirrel cage (induction mtr), very electrically robust, so re-using no probs.
The mtr lives in the drain pan assembly and with an easy strip down (which I have done) the drain pan separates from the condenser assembly (drops down). Problem being is that the d/pan drain hose going through wall to outside is stopping dropping the d/pan completely. LH side can separate from condenser head but RH side caught due to d/hose. Does anyone know how to remove this hose, please oh please? Apparently it is fixed to the pan with a screw (may also be glued?) but only having < 50mm between the wall and pan hose entry, cannot see + also can't get any tool in there to remove if there us a screw. The hose is flexible (it seems) and has a (insul) covering. Can this hose be cut further down and re-joined (if have to)? Would very much appreciate assistance with removing this hose, once done everything else pretty easy stuff...Thank you

Brian_UK
20-04-2021, 08:35 PM
Those hoses are genrally a push fit, albeit a hard push, try a flat blade as a twisting lever at the top of the hose where it fits the drain pan.

Rob White
21-04-2021, 09:41 AM
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From experience I have only ever known these to be a push fit and if you look up the parts list you
can see the drain with the push fit ends.

I don't think this model should be any different so as Brian says the drain hole fitting is fixed to the
tray and the drain should be a push fit over that (but there is always a first time).

What you call the condenser assemble is the evaporator (the condenser is outside) the drain tray
is flimsy if you are rough with it but if you can hold the pipe with grips and slowly pull and twist the
tray it should come free.

Rob

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Rob White
21-04-2021, 09:49 AM
.

Ps if you are capable of removing all the components and replacing the bearings
why not just replace the whole motor assemble yourself and have done with it?

You won't incur any labour costs that way.

But be warned one way for AC engineers to make money is to follow people who think
they can do the job cheaper themselves.

It is not the dearest option to get a professional to do it right first time, plus you have warranty.

Rob

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Tigercat
21-04-2021, 10:19 AM
Hi Brian, thank you for your reply. Indeed sir, oh, I just wish it were as you described, I would have had it all done and dusted, 10.3 days ago. Yes, I've been trying to get info and advise for this period. I can't find install/service manual, unless I sign up for "free" with c/card-no trust in this.

I can find some Fujitsu docs which have wall mounted units (not this one) which advise hose is attached with what appears to be a saddle(?) clamp and screw. Screw is not side mounted but goes straight in, same direction as hose. This is also backed up, by, there is no cut-out at the side to get to screw as installer would have used this to attach. Have also chanced upon some discussion where others mention pushed on and glued. Also in text others mention steps to take off d/pan, saying "remove drain hose" as one of the steps but don't tell you how. So if I go in there and heave on it I will stuff up the hose. Getting another hose back on will be another pain. So I'm trying to get as much correct info as I can so as to not cause more issues.

The d/pan is encased in polystyrene and the d/hose enters a hole in this and goes all the way to the plastic case inside (depth ~ 45mm)...so you can't get to it, can't see how it attaches (inspect mirror/lamp-no go), no levering with s/driver etc. Photos are attached.

AC shop, I got out initially, thinking their "service" would separate this d/pan to clean (yeah, office "Susan" said they would-but nah) only removed outside cover, fluffed around (temp/current check), charged me $140. I called later concerning d/pan, d/hose removal + mtr ~ $650. Asked how to - for d/hose removal, advised most are glued so they cut further back as hose goes out through wall to connect to solid drain tube (exits outside to ground), then re-join. So if no others can assist this may have to be the way. However the visiting AC dude did not seem too cluey so I'm cautious. However appears to be the only option or pay.

Anyone have an install/service manual for this ASTA24LCC it would be gratefully appreciated + still seeking knowledgeable advise. I'm not in a financial position to afford the shops cost + I've stripped it to the stage where once d/hose off I can complete and re-assemble. Thank you

Tigercat
21-04-2021, 10:46 AM
Thank you Rob...I respectfully hear your words and value what you have stated (thanks for correction on h/ware terminology). And I may have to look at the the AC Eng option. However, I'm out of work (E/Eng) at this point, so $'s tight but heaps of time + have taken on issues above this with no probs. All that is stopping me is a damn hose/lack of info. Reason for mtr repair (and not complete swap) is as noted from experience/knowledge, squirrel cage mtrs, rarely electrically fail. Bearings always eventually fail, easy to replace and cost effective ($20-30) compared to $200 for a new one (+ 20days wait to get). I also like to re-use where possible and not waste resources. Thank you for you tips on hose removal, I may chance it...? Many thanks Rob

Rob White
21-04-2021, 11:11 AM
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Try this.

http://spares.bigwarehouse.com.au/product_info.php?cPath=114_62396_81343&products_id=1679399


https://www.manualslib.com/products/Fujitsu-Asta24lcc-2783246.html

It shows the hose as a separate item with the flexible push fit ends.

Rob

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Rob White
21-04-2021, 11:21 AM
Thank you Rob...I respectfully hear your words and value what you have stated (thanks for correction on h/ware terminology). And I may have to look at the the AC Eng option. However, I'm out of work (E/Eng) at this point, so $'s tight but heaps of time + have taken on issues above this with no probs. All that is stopping me is a damn hose/lack of info. Reason for mtr repair (and not complete swap) is as noted from experience/knowledge, squirrel cage mtrs, rarely electrically fail. Bearings always eventually fail, easy to replace and cost effective ($20-30) compared to $200 for a new one (+ 20days wait to get). I also like to re-use where possible and not waste resources. Thank you for you tips on hose removal, I may chance it...? Many thanks Rob

Oh and that must be the politest rebuttal in internet history. :D

I like you. :D

The drawing I linked is slightly different in model but it give you an idea of what the drain looks like.

Rob

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Rob White
21-04-2021, 11:28 AM
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Try this exploded diagram.

http://spares.bigwarehouse.com.au/images/files/33241_c2c4e3072cc502d7e4c7e851e5240c7b.pdf

Rob

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frank
21-04-2021, 11:43 AM
If you look on page 14, item 50, you can see a small endplate with a hole in it. If your hose does not have one of these then it is just a push fit. https://guidessimo.com/document/321245/fujitsu-aou12rl2-service-manual-22.html

To replace the fan scroll, which I think is your original enquiry, then you are going to have to remove the drain pan assembly, the electrical pcb housing, the fan motor AND lift up the evaporator coil to gain access. This is quite a tricky process which, not only leads to "coil rash" :( (cuts to your skin from the fins), but can lead to fracturing the pipes. Not really a job for the untrained. Doesn't mean that it can't be done but be aware of the pitfalls.

If you decide to tackle this yourself, then good luck, and don't hesitate to drop back if you get stuck.

Brian_UK
21-04-2021, 01:13 PM
Tigercat, having looked at some installation details I can see your problem with needing to access that screw holding the drain hose in place.

Knowing that you have knowledge and tools my next question is - are you up to drilling a new hole in the wall to run a new drain hose?

My suggestiton is this:-

1. Cut the existing drain hose as far from the drain pan as possible.
2. Remove the drain pan from the unit and unscrew the existing drain locking ring.
3. Remove the blanking plug from the other end of the drain pan so that you can fit the repositioned drain hose.
4. Fit the blanking plug in the old drain hole.
5. Make a new hole in the wall to accept your new drain pipe.
6. Make up a new drain pipe to connect with the old existing part that you removed/cut off.
7. Fit the modified drain pipe to the drain pan.
8. Refit drain pan and test run some water through the pan.
9. Have a well desreved coffee or something stronger.

Tigercat
21-04-2021, 02:59 PM
Hahaha good onya mate; dear Rob, I've taken a shine to you as well. Nah, mate, that's no rebuttal. Just a sincere and genuine statement to say thank you for your advise and I'm in thought mode with what you and Brian have suggested. You and Brian are experienced in this area...me = 0, so I'm definitely in the listen up mode.

However my thought process is: 1)I heave on the hose and stuff it=more issues to fix it+new hose, Engineer heaves on it, stuffs it, extra labour+ exorbitant cost new hose + hose still has to be removed (cut and re-joined on outside wall) to re-join. 2)I heave and it comes off-yippee=$0, Eng heaves on it-still=$+450 labour charge. 3) I decide to cut hose (further along) where it routes along the outer wall, pull through wall, then re-join after-none of the above will occur, Engineer rocks up and says, yep I need to cut and re-join (as the advise given, via your ph call to us-which I was not overly trusting but options are limited), again still=$+450.

So, 3) has (appears??) the lowest risk for both. Hose is accessible on outside wall and is easily doable + need to (remember haha) tie cord around severed end to pull back through wall when pan re-installed

If hose is cut on outside wall (~400mm from where it attaches to d/pan) and pulled through the opening in the wall it will resemble the image in the manual you supplied, pan should then come off. I also found and browsed manualslib but the operator manuals do not show how hose is attached to pan...service manual (not available there/anywhere) would do the trick...found one prior for a Fujitsu (similar arrangement as mine?)

http://www.fujitsuklime.com/wf-doc/fujitsu-klima-uredjaj-zidni-inverter-asyg09leca-installation-manual.pdf

Page EN-4, shows how this model attaches drain. And even in this case, how to get to the fastener when unit is <50mm from the wall? No special tooling is noted to achieve this. Still looks like a cut and join unfortunately? I do hate cutting stuff though, always like to avoid.

Hey Rob it's great to be liked, haha, and I think I understand your sense of humour. Great to have a banter with you sir...Tigercat

Tigercat
21-04-2021, 03:27 PM
Hey thanks Brian. Yeah mate it is a PITFA. Yeah mate, I have a feeling it has this locking ring arrangement + funnelled down inside a 45mm styrene cavity until it meets the attachment point on d/pan. You are also where I 'm at. From the pics I sent the drain hose is visible going through wall to the d/pan. I was going to cut/remove unit drain hose (as supplied d/hose is not overly long) where it meets up with pvc (to drain to outside) on the other side of this wall (access no probs). Tie a length of cord around this end, then go inside and pull this hose through (with cord attached) the wall hole. It's a double brick wall, so approx 20cm distance from inside to outside wall + hole is large with space to maneuver hose through. Hopefully fix mtr issue, attach hose to d/pan and pull hose, via cord back through hole, refit d/pan. Haha, theory is always a tease though...

I very much appreciate your detailed, informative suggestions Brian. I could not go wrong in following what you have outlined...thank you

Tigercat
21-04-2021, 03:47 PM
Thank you Frank for the info. I can't see up inside where the hose attaches to the d/pan, it's buried in 45mm of polystyrene <50mm away from a wall. I sent Brian_UK (my first reply, so top of thread) x3 pics which show the situation. Yeah mate AC is all stripped down as you have outlined. Removing d/hose and all should be good to go....haha, and that sir, is where I'm caught and yes I'm a bit hesitant; I'm sure I can fracture pipes better than most ...very much appreciate your input and guidance, your points are noted, as I am very much untrained...Thank you

frank
21-04-2021, 04:56 PM
What you will find is that the plastic drain pipe which is moulded as part of the drain pan, travels through the polystyrene so that the drain hose can push onto it. The drain hose doesnt extend into the polysyrene.
Have a close look at the other end of the drain pan that currently has the stopper in it and you should see what I mean.
The drain pan is moulded this way so you can choose which end to attach the drain hose to suit your installation.

You can remove the drain pan with the hose attached so that it swings down out of the way but in my experience it is best to remove it to change the fan rotor.
I'm not sure that the drain hose is going to be your biggest problem on this project.

Tigercat
21-04-2021, 05:46 PM
Yeah, sorry Frank I did not choose my wordage correctly. Post #13 (to Brian_UK) explains better. Yes, the hose does enters into the cavity moulded into the p/styrene d/pan "shroud" and goes to spout on d/pan (can't see it but assume this is the way). And yes sir either end of d/pan can be used for drain purpose, I did note the LH side option. Indeed I thought the d/pan would swing out with the hose attached as you have suggested...but alas it did not.

Haha, that's why I'm chatting to all you nice folks because the brstd didn't/wouldn't do this, swing down. All the attachment points have been removed and the d/pan needs a gentle pull down to separate it from the evaporator (thanks Rob), from what I have gained from discussions on web (but no instructions given though-haha), just general chit-chat saved on forum boards from a few years back.

Sounds like you have had experience with this situation Frank?

Frank, I'm pretty sure you're spot on mate! It also may not be my biggest problem. Thank you Frank. I'm going to wait for a wee while and gauge all my options before any attempt(s)

frank
21-04-2021, 07:21 PM
What is on the other side of the wall where the drain pipe exits? Can this be disconnected to allow the original flex hose to be pulled back?

When we install these units, the lower half of the unit is pulled away from the wall on it's bracket to allow us to make the pipework connection. Seems strange that yours is only 50mm from the wall with no 'play' to allow access to the joints

Tigercat
21-04-2021, 07:57 PM
Hi Frank, yes indeed, that was what I had in mind. Yeah, I just don't think I had the guts to push areas around even though I have read (discussions) noting that the evaporator should move up a bit on it's mountings, allowing lower half to "drop down". I'm wanting to approach with the low risk mode if possible, I can fracture piping better than most I'm sure, haha.


Below is what I noted to Brian in post #13, concerning what I had in mind...Thank you Frank, I appreciate your knowledge and info, we all closing in on the same "page".


Hey thanks Brian. Yeah mate it is a PITFA. Yeah mate, I have a feeling it has this locking ring arrangement + funnelled down inside a 45mm styrene cavity until it meets the attachment point on d/pan. You are also where I 'm at. From the pics I sent the drain hose is visible going through wall to the d/pan. I was going to cut/remove unit drain hose (as supplied d/hose is not overly long) where it meets up with pvc (to drain to outside) on the other side of this wall (access no probs). Tie a length of cord around this end, then go inside and pull this hose through (with cord attached) the wall hole. It's a double brick wall, so approx 20cm distance from inside to outside wall + hole is large with space to maneuver hose through. Hopefully fix mtr issue, attach hose to d/pan and pull hose, via cord back through hole, refit d/pan. Haha, theory is always a tease though...

I very much appreciate your detailed, informative suggestions Brian. I could not go wrong in following what you have outlined...thank you

Tayters
22-04-2021, 10:35 PM
Hi fruity.

I've emailed a few manuals to the address on your vcard. There's the install, service and technical manual and also a file for getting access to the motor on newer units which might be of interest although it looks you are pretty much there anyway.
They are from my company email and might go to the junk folder so check there if nothing turns up.

From what I recall I'm fairly certain it is a push fit donkey dik (correct terminology!) on those units. If you can get a mirror on the spigot on the left hand side to confirm there is/isn't a hole to screw it in should confirm.
If so it could well be the rubber/plastic has stuck together and best way is to twist it free although I can see that is easier said than done.

Cheers,
Andy.

Edit: correct terminology falling foul of the language filter but you get my jist. :cool:

Tigercat
23-04-2021, 06:21 AM
Hello there Andy,

Thank you very much sir for the manuals (wow), very much appreciated. I have received them (x5 files) and will have a lookie. I'm hoping this ASYA model info has the same set-up as my ASTA(?). And also thank you Andy for your own info RE: hose fit. A massive help and a lot of effort from your side.
Yes from what I found here;

http://www.fujitsuklime.com/wf-doc/f...ion-manual.pdf

Not my model but similar, maybe...?
It indicates a screw access hole (on LH side as you suggested) combined with the styrene tunnel that accepts the d/hose. I cannot see this on the LH side (of my AC) but I can (I think) see an extra access port on the top (not side) of the styrene tunnel...will investigate further.

I will report back to this thread on what I find/where I'm at (have not tackled that pesky hose yet) ...as I'm still mulling over options and going through the fantastic response/info that all have supplied....
Many thanks Andy

Tigercat
23-04-2021, 09:52 AM
Howdy all....ah, some progress. Got back to having some more play to drop that damn drain pan before moving onto the drain hose. And I now have the complete d/pan dropped to where I can get to the screws (hopefully??).

Photos attached...

Previously, the LH side dropped no probs (basically without any force at all). Applied the same technique to the RH side but it seemed snagged, did not want to force it. So hopped onto this forum to see what others could provide to assist. A big thank you to all for engaging with me, as I'm new here and posses none of the following; knowledge, experience and information, however you guys do and provided much need assistance, guidance.

Ok. so here is the go to ----> I re-seated the d/pan to it's original level position ie. d/pan re-engaged to the evaporator (LH and RH side flush and level set under the evap) all fasteners still removed. Instead of having a go at the LH side then trying to move the RH side. I gave a gentle firm pull/wiggle (first) to the RH side and down it came, the hose allowed itself to bend down with the pan....yippeee. The LH side then became a bit of a brstd and needed some extra pull/wriggle but at least the d/hose is not there, therefore not the reason for snagging.

Now just have to maneuver screwdriver(s) to get the mtr holding screws out and then mtr should be free. Will take more snaps when mtr out and dismantled....Thank you once again

frank
23-04-2021, 10:45 AM
Well done so far......

To remove the motor/fan rotor, you will need to split the motor from the rotor.

If you look carefully into the rotor middle at the motor end, you will see the head of an Allen key or screw. The rotor design is cast to allow you to introduce a tool to loosen this. This is how the rotor is attached to the motor shaft. Once loosened, not removed, you can remove the motor by sliding it out to the right, leaving the rotor in place.

These rotors are 'balanced' to prevent vibration, and are easily knocked out of balance by either chipping bits off while removing or not cleaning them fully. Due to the cost of the replacement part and from experience many times of stripping, cleaning and re-building these units during routine servicing, only to find that they then vibrate, I used to always install a new rotor assembly if there was a need to strip them down. Saves no end of time and heartache.

The opposite end of the rotor to the motor end has a small shaft that locates into a small bearing that is located into a rubber bush mounting. This was also always replaced.

Tigercat
23-04-2021, 02:31 PM
Thanks Frank, no worries mate. Once I dropped the pan, Mr Newton assisted me with swinging the pan to the RH side and the whole pan came away (yes disengaged the hose as well). So yep, the hose was a push on (as others of knowledge have suggested). AC dudes advised it would be glued, many doc's showed it fixing with a fastener. So difficult to access and proceed.....

This hose and how it was attached was what was causing me all the issues...now I know how it goes, I'm pretty much sorted to re-furbish.

Yeah Frank, I did dis-assembled before I got your instructions, however, took great care with the blower scroll and the end bushing, have had experience with all this type of stuff before. I can see where they have added "weight" crimps (for balancing)to the scroll fan + it has some crude build up.

I note your tips RE: replace scroll/rotor + rubber mounted bushing and thank you. I'm in scrooge mode, so I'm going to v.carefully wash/clean scroll and re-use end bushing ($25 + 14+ days delivery/new)---I will re-grease end bushing with silicone grease. I can understand AC Eng replacing these though. But for me now knowing what I'm in for I will try re-using, as now taking apart AC is easy. If I run into probs can get back into it ok. Will get into splitting the mtr, swap out the bearings and all should be sweet. Thank you Frank for your valuable knowledge. I will post some more pics as I progress, hopefully may help others.

Tigercat
25-04-2021, 11:17 AM
OK - for those that may have an interest. Drain pan removed as per my last previous post. I have stripped it down, making sure that electronics (tether to frame with a tie) is not left dangling via it's conductors. Cover with a protector, preferably an anti static bag.

I've cleaned all the covers with a very mild detergent solution and used a directional garden hose sprayer to flush off/clean. BE VERY careful with the d.pan and keep e'tronics upright in a bag out of the way. I could not remove e'tronics due to hassle removing stepper mtr couplings. Using directional g/hose sprayer hopefully (+others as per photo) stops parts other than the pan itself from being flushed/spayed. Also X2 pivot points for the louver system were seized, stopping swing from operating correctly - used silicone spray to release, after d/pan dry, lubed all these pivot points with this spray.

The scroll/blower fan was a chore as it was covered in tiny (<1mm) flies (hundreds of them), stuck on big time. Put this in my bath + water/deter with a thick towel under it to stop any damage when moving it around. I used a very mild detergent + paint brush + a gentle blast from the g/hose (after bath)1581215813158141581515816 to get those brstd's off. Installer did not seal hole in wall that's how they got in.

Fan/blower mtr is out (pic). Just above the Panasonic sticker a divot/gap is seen, there are x3 of them around mtr housing. This is where a "punch" of sorts (s/driver) can be placed. Bore a hole in a piece of wood to accept and support motor spindle, insert spindle and tap punch at divots with hammer and the cover should come away. Will post more once I get this mtr cover off (haha, hopefully).

Tigercat
25-04-2021, 11:27 AM
Photos continued....1581715818158191582015821

And Frank's suggestion to replace with a new end bush is a damn good idea (thank you Frank) even though I was going to reuse the old one...new one makes good sense, even having to wait to get it.

Forum brd s/ware only allows x5 photos/post, so more photos in next post.

Tigercat
25-04-2021, 11:34 AM
Fan/blower mtr removed. Cutout/divots in mtr housing noted above Panasonic sticker. Can tap with "punch" (x3 around circumference) and remove the aluminium coloured mtr cap....yep, there will be a circuit brd under this + top bearing. Will post more when into mtr1582215823

Brian_UK
25-04-2021, 02:21 PM
Now you know why we servicee technicians always looked forward to a full service on a split when it is mounted in a shop or office with minimum working space and limited time.

Glad to hear that you're making progress.

Tigercat
25-04-2021, 03:17 PM
Yeah Brian_UK, hat's off to all you AC Engineers. I have far more time to play with this AC. All of you professional's will be on a time budget. And I appreciate why you would swap out old for new - time, difficulty and you need to supply a warranty...can't do that with old refurbished parts.

Sheeez, I'm glad I won't be at this again too soon...haha, have not got it back together yet and it might knob itself when I test it...has been good learning new stuff and meeting others of knowledge though...

Tayters
25-04-2021, 09:47 PM
A sterling effort so far, those Fujitsu drip trays aren't for the faint hearted!

The difference in the model number denotes the region or voltage supply so you are all good there.
I've stripped similar fan motors just to take a look and bearing replacement looks pretty straightforward. Like you say there will be a circuit board in the motor but the rotor will pull out easy. Not sure about the rear bearing, not taken one of those apart but guess that cover pops off somehow.

Cheers,
Andy.

Tigercat
29-04-2021, 03:12 PM
Hey thanks for the encouragement Tayters (and Brian_UK). And yes you are spot-on RE: manual mod#'s. As I had a quote for mtr replacement, at my request, just prior to me attempting. And your mod# (manuals) is also stated on the quote together with my mod#, thanks mate.

Haha, yeah that drip tray does have a lot going on.....

Indeed, cct brd will have some solder points to remove. Then brd can be removed (needs to, for bearing clearance) from mtr casing and the rotor will come out completely, with, front and rear bearing retained on the shaft.

Been a bit crook, so have not split mtr. Maybe tomorrow? Will add some pics soon

Brian_UK
29-04-2021, 08:02 PM
Struggle on dude, you'll get there. ;)

Tigercat
30-04-2021, 11:02 AM
Ok my AC friends, here we go with the split. Bore hole in a some wood to act as a holder for mtr shaft, deep enough (+ diameter just > than shaft) to hold shaft but not too deep to stop cast mtr cap from moving down. I must thank a Y/tuber for this idea.

Put some datum points (marks with screwdriver/indelible marker etc) that will allow cast metal cap to align correctly with the rest of the mtr body when re-assembling. As there is a driver chip (white mark = heat sink paste) that needs to be resting on metal cap (to dissipate heat)+ always good to re-assemble in the same orientation as originally assembled.

Use a s/driver and gently tap (downwards) at the divot points (shown in previous pics) and cast metal cap will then come away. Hahaha, now I did this as gently as I could, however, some of the plastic making up the rest of the mtr body came (broke) away with the metal cap. This is the dark material visible inside of the cap on the circumference. I may not have been consistent in applying force around the whole cap, I think....damn you stupidity, you always follow me. Should not be an issue as it will be assembled back as per original location.


A small dab of glue (high temp) should secure this area and hopefully shaft alignment will remain ok. I will use a high temp super glue to do this as I don't want any volatiles associated with the glue to cook off and seep past the new bearing seals.


There is a compression washer that sits on top of the front bearing (photo).

The cct brd has x3 solder points and some plastic welds holding it in. I will tackle these soon and document...hopefully this evening, got to hit the pool now for some laps.

Tigercat
01-05-2021, 12:03 PM
Alrighty then...Removal of fan mtr pcb. I used a decent soldering iron that I normally use when I populate a pcb and subsequently solder components to the board. Mine has an adjustable heat setting that I cranked up reasonably high (photo).

We want to de solder those x3 solder points (photo showing black dots at points), as they are chunky points we need some high temps. This is needed to melt quickly and clean the solder, limits the amount of time applying heat (too much heat is destructive). I then used a pneumatic solder sucker to vac up the molten solder. Reasonably straightforward, if you have experience....potentially disastrous if you do not. The x2 plastic welds (photo black dots) can have their tops carefully broken away using flat blade jewellers s/driver. Then carefully pry up the pcb, access to remove the complete rotor is now available.

Photos show tools used etc and rotor out, showing bearings. Bearings seem rather "dry" with some axial/slop movement. I don't have a small enough bearing puller to get them off so have to have a think what to apply to remove them. There is a c/clip behind each bearing, best to remove these before bearing removal. Also be wary, rotor is very magnetic and will find any ferrous material lying around to suck-up. Yeah, like fine little bits that will stick to rotor. Just BTW, same place where my soldering iron (photo) was made is where the bearings were also made...so, there's ya problem. I will be back with bearings off, haha, hopefully...

Tigercat
02-05-2021, 01:37 PM
OK, bearings have been removed.

I'm very aware that you guys/gals will know all of what I'm doing (or have done-as it is your profession). And my documenting, is only to show others, such as me, with limited knowledge, limited appropriate tools, limited $'s but good amount of time available, a way to go about repairing (hopefully-not there yet) an AC fan mtr (+other things along the way).

Big problem is/was I don't have mini gear/bearing pullers, I have pullers for auto use - too big. So had to improvise with what I had available.

Front bearing I used all that is in photo#06 (+piece of wood to tap mtr shaft). Clearance/distance from rotor to bearing is limited to fit tools into. Used an old bike multitool (#1) to slide under bearing (via gap in tool). Make sure to protect rotor - hence bubble wrap. Held the longer end of the m/tool and supported smaller end on the edge of my desk. Arrow on m/tool is where shaft + bearing supported. Applied some spray on lube to shaft, gave the mtr shaft some (non forceful) hits to move the bearing further up the shaft. This allowed tool #2 (auto ball joint splitter) to then be used. The piece of inner tube rubber used to cushion shaft end - to not burr or distort it.

Rear bearing as per photo#05. Same arrangement as front bearing, however could not fit #2 into clearance. So kept #1 under bearing supported via tool box corner (as needed more than two hands) and tapped on mtr shaft with tool #3 (brass plumbing valve extender).

All good, bearings off, no distorting of mtr shaft ends and no damage to rotor. Keep the b/wrap under the #1 tool to stop damage when tapping.

Keep in mind hard hits to magnetic items, IE the rotor, may disrupt their magnetic properties (heat will also affect as well), so go easy on the hits to shaft and no heating.

If I had appropriate brass drifts would have been better. Took < 8 minutes to remove bearings. Time to cook up a scheme on how to do it took the time...if one has mini pullers etc, would be easy as.

Just out of curiosity I weighed the old bearing(s) = 12 grms. I'll weigh the new bearing(s) and see what they come in at. Bearing specs; OD=22mm, ID=8mm, D=7mm. When I have new ones, will add more documentation. Photo#06 in following post...

Tigercat
02-05-2021, 01:39 PM
Photo#06. Shows what I used to remove front bearing...15842

Brian_UK
02-05-2021, 03:29 PM
(as needed more than two hands)

I always maintained that our assistants should come with arms containing seven elbows if they wanted to be of any use at all.

Tigercat
04-05-2021, 05:22 PM
Haha, that gave me a good chuckle Brian. Get a move on evolution....I've got things to juggle. OK, I have got the bearings. They are, an ubiquitous, # 608zz (Timken for me + many other brands available), easy to get and cost effective. I'm still waiting on the blower fan end bearing/bushing to rock up...a 2,700km journey from South Oz. We wait for many days/wks for goodies, I think in the UK, you get goodies in a matter of days....?

Hopefully will have a go putting new bearings on rotor shaft tomorrow. Thinking a 10mm deep socket (as inner race od ~ 10mm) + F clamp should do the trick(?), we'll see how it goes + will include some tips to allow the "motor drive" chip (on cct brd internal to motor) to have a more effective heat-sink.

CarolynVJ
05-05-2021, 07:25 PM
Hahaha a joke with seven elbows, I appreciated, or it was not a joke ... In any case, I was reminded of this one funny story. I had an air conditioner since 2010, no one followed it. It so happened that I had to call the guys from airconservicingsingapore.com (https://www.airconservicingsingapore.com/installation/). One guy came to me, he was so pleased, called him to service the air conditioner. Everything would be fine, but my air conditioner is in a hard-to-reach place. Together with this guy, we somehow got him, but this poor fellow hit his elbow, apparently a nerve hit or something. He portrayed such a face, I suggested that he take a break and take a break, but with a smile he said it’s not worth it, although it was clear that he was in great pain. If possible, he would use foul language. Oh, he was a funny guy, of course, after the renovation, I offered him a cup of tea, and we got into conversation, as he worked the last day, that's why he came to me so happy.

Tigercat
07-05-2021, 03:46 PM
Apologies to all...have been busy, and have not got to the bearing install + the blower end bearing has just rocked up today. Will give it a go tomorrow and can now assemble the motor + can install the motor + blower into the d/pain and get that section completed.

And, Brian_UK, CarolynVJ (do you bounce a lot?); don't forget, Chernobyl has not yet finished providing "gifts". So 7 elbows might be available in the near future....

Photos of internal motor circuit board shows chip with white on it. The white is a thermal conducting paste. The chip is involved in driving the inductance magnets (coils) in the stator. So we have v.fast current switching with respect to time (di/dt), therefore lots of energy = heat. Upper chip surface will be designed as a dissipation area and the paste thermally "connects" the IC to the mtr metal cap, which will act as a heat sink and release the heat to the outside.

However, I have noticed, that the paste on the top of this IC is now pretty much dried up (solidified). It should be a pliable paste to work effectively. This needs to be replaced. I will do this when assembling the mtr (& advise how to). Because at this point it's doing bugga all for the IC and chucking the heat back inside the mtr housing and will be the same in motors that have some age. Plus I have some (easy) info on testing these motors (+others), might be useful. I will post the link next post...

frank
07-05-2021, 06:47 PM
A good job takes time. Any 'coil rash' yet 🤣

Tigercat
07-05-2021, 07:06 PM
Yeah, mate if I'm reading you correctly (??), I have found some. I can see where the laminations that form the core of the electro-magnets, that face the rotor surface are missing a bit of their "coating". Looks as if the rotor has just scrapped the surface, but I don't see any marks on the rotor surface.

Hey Frank, would this be consistent with bearing wear? Could it also be due to blower bearing end wear? With these two in mind, maybe a combination of both(?)...enlighten me please.

Tigercat
08-05-2021, 12:07 PM
OK, bearings are now installed. Photos will show what I used. Unfortunately, the 10mm deep socket was not viable. Instead I used the expansion sleeve that is used on a "hold fast" bolt. It is 10mm and I put some cable ties around the outside so it did not deform when clamp applied...that was for the front bearing.

Rear bearing, used a washer, hole diameter just over 8mm (to distribute the load), placed a 9mm socket on top of washer, which is sitting over bearing inner race and gentle tap with hammer.

Haha, make sure c-clips are on shaft first, applied wee bit of silicone lube on mtr shaft, then install bearings + they must sit flush with c-clip. Motor assembly next post...

I did weight the old bearings, came in at 12grams. New bearings, also = 12grams. And I could not see any bearing lube/grease inside mtr housing, so assuming the old bearings did not de-lube.

Tigercat
09-05-2021, 08:09 AM
Ok chaps, here we are, re-assembling the motor. First off, I will need to rescind two bits of info I discussed in my prior posts; 1) way back I noted that the fan motor was a squirrel cage (inductance) motor...this is not the case. Because as I continued dis-assembling this mtr, I did note to be wary of the strong magnetic field of the rotor. I was then aware that due to this, we have a (permanent magnet) brushless DC mtr (it still works via inductance) as the stator (electro magnets) are DC pulsed, influencing the magnetic field of the rotor ---> squirrel cage uses AC and induces rotor and stator.
And as with the squirrel these DC mtr's are also pretty electrically robust, can handle stall conditions reasonably well-until protection sense circuit kicks in.

2) more recent post, I discussed that the heat-sink compound (white, on top of mtr drive IC) had dried up and was not doing the job. I started to remove this compound and noted that it was rubberised, normal h/sink compound goes flaky/crumbly. So, this may be a more specific compound to "form" around components/heat-sinks and still transfer heat. Therefore I have not removed it but I have added some more h/sink paste...this will assist in a more efficient transfer of heat to the mtr cap. Not really necessary but while I'm in there, might as well. If it dries up the original h/sink compound will still do the job.

I used my normal vacuum cleaner with small nozzle to clean rotor and inside mtr housing (stator poles) to remove any rubbish. Then sprayed rotor with small bit of silicone and wiped around rotor with clean cloth. Because rotor to stator clearance is extremely small, don't want any crap in that gap.

Photos added showing assembly, #01 h/sink compound used + plastic shield that fits just under mtr cap. #02 shows scuff marks on stator poles must be from rotor but no visible marls on rotor. Slop due to mtr bearings and blower end bearing probably causing this, as rotor to stator clearance very tight. #03 Rotor in without PCB. #04 PCB in and I re-did the plastic rivets, melting used cable tie to the x2 white points (black dot marks)---maybe not really necessary as x3 solder points should secure it, but easily done. #05 PCB re-soldered, socket used to make sure brd is firmly located in its position. #06 shows mtr cap and plastic shield + front bearing compression washer. #07 shield in place, it is specific in how it fits. #08 shows h/sink compound (added to IC)+ silicone paste, used (v/small drop) this to hold compression washer in place while mtr cap put on, s/glue not used at this point. #09 used a 150mm gear puller to make sure cap goes on evenly, socket (sized to just fit rear bearing protrusion) at rear of mtr to centralise puller. #10 tapped (gentle hammer) on mtr cap to secure it then used puller to pull it onto mtr housing. #11 shows what I will use to keep mtr cap attached to housing. I will secure a few points around the mtr housing circumference, clean these areas with alcohol, scuff up with emery paper and use the s/glue to (hopefully) secure mtr cap.

NOTE: the green (paper) shim indicates that there is a slight gap present between cap and housing. I was not aware of this and cranked up the puller to remove this---yeah, not good, then realised gap was normal (I hope?). Puller is tight enough to secure cap, too tight and the bearings will bind. Can check, by spinning mtr shaft, should be smooth with no mechanical noises. I chose to glue on the outside of motor (to secure cap) so as to not introduce contaminants to the mtr internals, even though s/glue is a hi temp variety. At the moment cap is still secured by puller and I'm about to hit it with the glue---I'm thinking 4-6 spots around circumference should hold it (haha??), have to see how it goes once glued and puller removed. There are 11 photos so they will be spread over x3 posts. Next post will supply a link to a good info resource for these and other motors.

Tigercat
09-05-2021, 08:32 AM
Mtr-assem, continued.

I also hope it is ok to supply this link? And a big thanks to the supplier of this info - Dennis, it seems. It discusses succinctly (because I'm a waffler) this style of motor + others used in Air Con areas. Gives the function of and wiring on connectors. If you are safe/have knowledge with AC mains supply, you could even make a tester, very easily. This will help in evaluating the status of the motor drive circuit and mtr itself. As feedback comes from the mtr and operation can be displayed via the tester (if ya make one, that is) ie: LED to indicate f/back pulses etc.

https://www.whatwoulddennisdo.com/dc-motors.html

Just make sure everything (different voltage sources etc) are tied to the required common ground, which is discussed in this write up.

Anyway, Mtr-assem photos continued....

Tigercat
09-05-2021, 08:37 AM
Mtr-assem continued, last photo #11.

I will now attend to securing the motor cap with the super glue adhesive discussed. And hopefully mtr can the be install onto the drain pan. Will be back to advise if successful and hopefully have it installed on the d/pan...

Tigercat
10-05-2021, 07:43 AM
The fan/blower mtr is now completed, s/glued mtr cap at 6 points on outside of mtr cap. Spins freely with no binding or mechanical noise, so should be a goer. Photo shows mtr with front and rear rubber mounting bushings attached + blower scroll end bearing. One with white dot = new, other = original (old one). Next step is to mount mtr + blower scroll and blower scroll end bearing into drain pan.

Brian_UK
10-05-2021, 12:42 PM
time for a coffee... or a tinnee...

Tigercat
10-05-2021, 02:02 PM
Indeedy Brian_UK, spot on mate. Just back from a swim and have a coffee in hand as I type. A VB will be happening when all completed...might get to installing into the drain pan this evening...? Thanks for your support mate...always appreciated. I have also enjoyed documenting the process/progress....

Brian_UK
10-05-2021, 07:40 PM
As a sideline you could take up technical authorship, when you have a spare minute or two of course.

frank
10-05-2021, 08:47 PM
I'm impressed with the motor repair.

I would have just put in a replacement ������

Tigercat
12-05-2021, 09:09 AM
Motor now installed in drain pan.....

Thank you Frank, and yes sir, I agree 100%, ideally a new motor would be the way to go.
However, for a DIY'er this is an alternative, total material cost = $14 for bearings. Silicone lubricants I had already, if you needed to buy = $20 and re-usable for other stuff.

If you have some appropriate tools, AND were not held up by how the drain pipe attaches, time to do, approx 3+ hrs, maybe. I have (had-haha) a decent "workshop", in my garage attached to the house , with benches, vices, drill press + other helpful goodies etc. But unbeknown to me a hoard of flipping termites found my work benches delicious and devoured them. Leaving them looking untouched on the outside but all hollowed out, so I could not use anything attached to these benches; haha went to tighten the vice and it just peeled up and dropped off. Therefore, I had to improvise and working out an improvised strategy consumed most of the time.

The scuffing to the stator (as per photo previous) should cause no issue in mtr operation.
With the blower attached and mtr secured in the d/pan bracket it spins great. In photo#01 the swing stepper mtr (in-between) green and red steppers (at bottom) needs to be removed completely with the white securing bracket to remove blower mtr shroud when dismantling. In photo #02 the fan to shaft locking screw is visible, this needs to be made secure with a locking compound, haha, your partners nail varnish will do just fine. Also can use her lippie to lube nylon gears and mascara for marking things....no, don't even try it, haha. Photo #03 shows blower end bearing fitted-it just slides into a locator bracket, easy.

All good so far. Next is to fit completed drain pan. In the interim time I'm going to straighten out some evaporator fins, I did not bend them, found them that way when covers came off + vacuum out any dust in the evaporator area + try and pack some foam into the hole in my wall that the installer left bare. Then will re-fit d/pan + re-assemble circuit brd, fit and check electrics. I'll leave the covers off when I test operation as my confidence of complete success is not there. And the main cover is a PITA to remove.

frank
12-05-2021, 10:46 AM
I would suggest that you finish off the wiring and test run it without the drain pan in place. Could save a load of grief if you come across any issues and have to remove the motor again. Running it for 5 - 10 minutes without the drain pan will not cause any damage

Tigercat
12-05-2021, 11:24 AM
That's a good idea Frank, thank you. I will do this...I'll support the d/pan (without connecting it up to evap) with some cord so I don't put wiring under stress and fire it up. Good call mate TA..

Tigercat
14-05-2021, 05:30 AM
OK, so I tired to implement your good idea Frank. Unfortunately the mains power input terminates at an electrical terminal block on the d/pan. D/pan assembly also houses the e'control board, which also connects up to sensors (thermo etc) attached to evap. So to test the mtr without fully mounting the d/pan means extending pwr wiring and then sensors on evap cannot be attached to control brd due to d/pan now being at at distance that does not allow these sensors to be terminated on control brd. Therefore d/pan has to be fully mounted to the air con system....dang it!!

Tried last night with a helper to mount the d/pan. And again I'm caught with not being able to attach the d/hose to the pan spout, limited space to get in there and push it on. As d/pan has to be mounted first and then hose attached.

Again the (only?) option at this point is to remove the hose (connecting to pvc tubing) on the opposite side of the wall and feed enough of it through the hole to allow me to connect it to the pan. Then fit/mount the d/pan completely up to the evap as required, pushing the hose back through to the other side of the wall at the same time and re-connect to the pvc. Problem is, that installer has taped (securely) the d/hose to the refrigerant pipe in the wall cavity, difficult (if not impossible) to get to/remove this taped area, to allow free movement of d/hose.

Any ideas from others most welcome as this is becoming an absolute PITFA...

Tigercat
15-05-2021, 09:26 AM
Arriba!! - righty'o....photos showing finding and cutting that f00k'n drain hose set-up, on the opposite side of the wall from where it exits to mate up with the drain pan. Previously the hose was too short to successfully get it onto the pan. Cutting where it mates up to the pvc drain to the outside now gives some extra length inside to (hopefully) attach to the pan, pic#04.

Pvc was cut with plumbing pipe cutter(pic#03) that I had at home, used previously to do some plumbing mods. I'm sure, no probs using a small saw also. When d/pan fitted, hose will be fed back through the wall and re-joined, with what/how --- will work it out when I get there.

Tigercat
18-05-2021, 02:30 PM
OK, have been procrastinating a bit. So, have just now re-fitted the d/pan onto the evaporator. I had a helper, which I felt was necessary, made it reasonably easy-ish to do. D/pan hose easy to fit with that extra length, pushes on snuggly. Had to wiggle and juggle some-what to get the pan in place. Then as it slides up towards the evap had to bend the plastic tabs at the bottom of the pan up and over the two brackets that the pan rests on. these brackets are part of the wall bracket that secures all onto the wall.

The d/pan hose needed to be gently pulled back through the wall as the d/pan was positioned under the evap and then pushed up to engage the two brackets. I found using some silicone spray was of great assistance to allow things to slide and move.

At either end of the d/pan there are two screws that now need to fitted to secure the pan to the evaporator. At this point the pan is just sitting there, held by the two bracket locators...all good.

I'll be back once I fit the screws, pan to evap. Also need to fit the controller board and plug in motor and sensors +hook up mains pwr. These connector plugs are sized such that they will only fit the appropriate receiving receptacle on the cct brd, so no issues at getting it wrong.

Tigercat
18-05-2021, 04:33 PM
Righty'o then, photos #01-->#04; sequentially shows: cavity to slide pcb into, pcb mounted, pcb with transducers/sensors connected to pcb receptacles + (ac) mains input terminal block, with x2 mains earth(s) terminated, terminal block fitted + (ac) mains input conductors terminated. Mains was pulled through the rear acceptance hole via cord. Difficult if you try to feed through from the rear.

As I can do stupid as good as anyone else, I checked (m/meter) that mains has no short to earth, ie: terminal block with mains fitted, check to air con earth. Check ac earth from air con earth(s) to established mains earth, in my locality ac earth resistance is <=0.5 ohms.

Covers will be left off, in case I have made a stuff up, I'll power it up tomorrow. As it is nearly 12pm, and if issues happen, I would sooner it be in daylight.

Brian_UK
18-05-2021, 06:04 PM
You're getting there...

Tigercat
19-05-2021, 09:52 AM
Hey thanks Brain_UK.....It's all powered up. I've turned on the air con and all is great. Nice and quiet, blower motor is performing well, on, all speeds. Hahahaha, however the x2 vertical louvers are not operational, the lower single large vert flap assembly works no probs. I have used a screw driver to place on this vertical louver stepper mtr and the other end of the s/driver to my ear. I can hear this s/mtr operating each time a command is generated via the remote. So, it appears that the vertical louver mtr is working but not engaging mechanically...muffed it, dang it!

Yeah, had a thought I may have an issue in this area when I disassembled the d/pan when cleaning it. Maybe I have not set-up the louver gearing/stepper mtr engagement correctly. Looks like I can get to this area without removing the pan. Haha, fix one and muff another, so back in I go. Will look into it this evening...at least the mtr and blower assembly do not have issues.

Brian_UK
19-05-2021, 10:11 AM
You know what they say, "90% of the job is complete, the other 90% is snagging".

Check the louvre linkages to make sure that you're not 180deg out and the links can be simple slot and tang joints where the tang has snapped off.

At least you can look at the problem in the cool now. ;)

Tigercat
19-05-2021, 11:41 AM
Haha, a well deserved saying Brian. And thank you for your info sir, much appreciated. I will have a lookie later this eve. I need to bash out some laps at my aquatic centre first, when I get home I will give it a go with your info in mind. It's now winter down here mate, so I'm seeking some warmth...but yes, it heats and cools great..but something I have/or have not done is causing this issue, that's inexperience for you...learning on the run. Will update my progress....

Tigercat
19-05-2021, 04:06 PM
Back to it...easy to remove the vertical louvre/louver stepper mtr. One screw and the mtr pulls out and has a gear on the output shaft, this needs to come out also, as it is a key-way fit.

Mtr is driving, hold in fingers, can feel step of the rotor. However, reduction gearbox attached to mtr has an issue (crack in gear, stripped teeth etc?). And for some time now the louvres have had an issue, top and bottom sticking together....so stressed for some time. Why it has let go now? Louvres were positioned correctly (marked them) and when I started it up today there was no movement at all from louvres....so seemed to be knackered prior to re-fit? Maybe when I cleaned pan, handling applied some force to louvre blades back into the already stressed gear...

A new one no probs ($25+14day wait) and might be the best way.....Buuuut (fixed one-why not another), there are x4 tabs that hold the g/box cover and drive bushing on. I tried to bend these tabs up, thick tabs, starts to distort motor casing when attempted. I'll reduce the thickness (file) of these tabs to allow bending up or remove the tabs completely and solder cover back on, this metal should accept solder.

Cracked nylon gears can be fixed (reasonably easy) and are normally reliable, when done correct. Hmmm, stripped teeth, nah; anyway once inside we'll see what's up and take it from there. If it's doable, I'll give it a crack - don't have to wait the 14 days post, no go --->order a newie...

frank
19-05-2021, 05:23 PM
Without the louvres in place, can you see the motor spindle turn?

Tigercat
19-05-2021, 06:54 PM
If you are referring to the louvre mtr Frank, no the drive spindle does not turn but I can feel the stepper mtr cogging/stepping...so mtr=ok, gearbox=problem, I'm thinking output shaft is has come loose from final drive gear, can fix + be reliable. If asking about blower mtr, yeah working a treat, no probs.

al
19-05-2021, 08:42 PM
Hell of a thread Tiger, keep going!

frank
19-05-2021, 10:31 PM
Yes, sorry it was not clear

I was talking about the louver motor

Tigercat
20-05-2021, 10:56 AM
No worries Frank, I hope I answered you enquiry... Photos show g/box with top cover off. I filed away the tabs holding it to the g/box housing. Trying to bend up the x4 cover holding tabs distorts the g/box housing, so easier to file off these tabs. We can glue or solder this cover back on.

As per photos, all the gears look in good condition, no cracks or munched teeth. The final drive gear with drive shaft is shown. And as I posted previously, my thoughts were that this drive shaft has become loose within the gear (and that seems to be the case), ie: the drive shaft, under load, rotates independent of the gear it should be affixed to...d/shaft should be solidly attached to this final drive gear. But grasping this gear firmly and applying a turning force to the d/shaft causes the d/shaft to turn and the gear remains stationary...so that is our problem.

The fix = clean big time (detergent/alcohol etc) to remove grease etc. Push the d/shaft out of the gear, abrade the area that will be bonding to the location hole in the gear and use some epoxy (2 part) glue. Will also apply glue to the external parts of the d/shaft that contact the surface of the gear. Let glue cure well, then reassemble. To test = installing into air con, leave loose so I can grasp the output d/shaft (pliers) and run louvre cycle and (nearly) stall the stepper mtr a few times. If it can handle that, should be good to go... Photos will be in this post and a following one

Tigercat
20-05-2021, 10:58 AM
OK, the last photo...shows tools that were used...pretty easy to do. Also final drive gear with drive shaft is shown sitting on the g/box cover. I was hoping to show the internals of the stepper mtr because they are an interesting design, alas it's sealed up. I have used stepper mtr's in many circuit designs, haha, but have never split apart small ones such as this. However, I'm confident the repair will be successful... Oh, and thank you, al, for your interest.

Tigercat
21-05-2021, 10:36 AM
All right then --- please disregard what I noted in POST #67, I GOT IT WRONG. Had a bit more of a think last night concerning the final drive gear and associated drive shaft.

The reason why I assumed the d/shaft had come loose within the drive gear, is that, I can grip this gear and applying some turning force (via pliers) to the shaft it turns independent of the final drive gear.

This final d/gear and d/shaft are meant to be this way, so no problem (I failed to examine other/this possibilities) with this system. REASON BEING, this is a clutch. As the louvres move up and down, they need to stop at their maximum deflection, going down and going up. The way this is sensed, is, by the louvers coming to the end of their travel and applying load to the mtr when they do so, thus, current draw by the stepper mtr increases and the protection cct monitors this and sees current increase above the normal running current. Due to this, supply to the mtr is terminated and stops the louvre travel at its end stops (down and up max travel).

And the d/shaft is located in the final gear drive with a clutch mechanism. When the end stop is reached this clutch engages applying extra loading but not completely stalling the d/shaft, therefore current increase is sensed and mtr power terminated. The clutch arrangement stops damage to the g/box and mtr by using a "soft stop" arrangement. That's why I could apply force to the d/shaft and turn it independent of the d/gear.

Ok so I re-inspected the gears under some high magnification and found that the second d/gear had a few teeth with some distortion on the tooth faces and the gear valleys had closed up a wee bit.

Solution is to try and "re-profile" these areas. Use a sharp bladed cutter, such as in photo (scalpel is best but can't find mine). Scrap/shave away very small bits of nylon that look out of place on the gear face and then open up the valleys buy cutting/scraping further down into the V. Photos show how to go about it. This technique can be applied to any nylon/plastic gear teeth. It is mainly the distortion/bunching up of nylon at the bottom of the V that causes gear binding, gear face correction should occur as the teeth interface with another gear. CLEAN out between the teeth with a tooth brush/running water.

Louvre mtr now works great. I have reassembled and applied cable ties to keep g/box cover in place. Before reassembling, silicone paste (as silicone is nylon/plastic safe) was used to lube all gears and metal d/shaft + bushing. I opted to use a Tarzans grip (shock proof) super glue to secure the cover at the points I filed off + the area where the bracket screw holes are. This should be ok + can potentially remove if need be, will solder if this is insufficient. This glue has full cure @ 24hrs, but should be ok later on this eve, so, will refit and test later tonight....

Brian_UK
21-05-2021, 11:50 AM
Okay, so nearly finished.

What is your next project? We can't have you sitting around idly drinking beer and watching TV now can we?

Tigercat
23-05-2021, 10:01 AM
Yes indeed Brian, nearly finished, just need to fit the covers.
I have had the AC running at 25 deg C with the "swing" (vertical louvres) engaged continuously since Friday evening. Unit is running beautifully, blower mtr, responsive and quiet and the little vert louvre mtr that I did some surgery on is operating like a charm, no noise and responding to its end stops/changing direction as it should do. Hahaha, so I'm pretty chuffed as well....as it has just started to get a bit chilly down this way.

Haha, Brian, I try not to have too much happening but I just love machines, whether they be electric, electronic, mechanical, pneumatic or anything else. I give everything a go, gets your brain working, saves $'s and alleviates wastage, machines like to live on (so they tell me).

I'm pretty good at the electronics/electrical area (E/Eng), other areas I learn about by putting thinking hat on and from others, in person, or from areas, such as your fine forum board and from reading about other knowledgeable peoples information/experience. So I thank you: Brian, Rob White, Frank, Tayters and al for personally engaging with me and allowing me to post this repair on your forum board. And thank you to the other members for showing an interest for what I've been up to.

Hahaha, it all started with that flipp'n drain hose.... I rarely join forum boards and have NEVER documented my progress for others. This board has allowed me to do so, even though that was not the plan. However, I always take photos when doing a project (keeps conceptual ambiguity in check) and as I was doing this for my AC and submitting this to your board for response to my questions, I thought I'd keep it going. And, I think it fair and just to add commentary to complement the process and photos to keep others informed as to what is taking place, instead of leaving them guessing...what's this geeza up to/what took place there etc.

So, Brian, I really do like to sit around and do bugger all mate, if I can - but that fleshy processor/control board in my head keeps tempting me to get in there and make/fix things.

Now, I'm onto repairing a verge "chuck-out" 55" Samsung LED flat screen tv. It has ghost/double/lines on screen, image issues. Pretty easy fix. Photo #3 is the T-con (timing and control) brd and the x2 (white/black) clamp connectors at the bottom of the brd supply, via x2 ribbon cable, image signalling to the screen. Clean the "finger" contacts on these connectors with alcohol (cotton swab)+ clean ribbon cable interface contacts. Wait until alcohol evaporates, re-insert r/cables into connectors push down clamps to secure x2 ribbon cable, all should be good.

This is a common issue on flat screens, oxide layer (over time) forms on contacts, increases resistance across this contact area. Then we have a volt drop, Mr Ohm steps up, V=IR, across these connectors, subsequently supplying the screen with a signal it cannot process correctly = bad tv night.

I have a lot of experience in circuit design/analysis/testing + repairing to component level (including surface mount) of many varied e'systems. And I would like to stay around on your forum board, Brian and Frank. I (hopefully?) may be able to assist other members with electronic issues. Once you isolate the offender, it's pretty straight forward (even for novices/limited ability in e'tronics) to get it sorted. Failing Electrolytic capacitors (DC ccts) are the nemesis of all DC systems. These caps are about the only components in the electronics environment that have an actual life span (thousands of hours, cost and manufacturer dictate the good ones), all the rest pretty much indefinite (when kept within parameters). Bad caps, will influence all other componentry operation, leading to false diagnosis if you are not aware....

All righty then, I still need to fit the covers to my air con (have fitted filters for its trial run) and re-join drain hose I cut to give d/hose some length....so will be back with some snaps, when done.

Brian_UK
23-05-2021, 01:49 PM
So glad to hear/read that your AC is behaving as it should do, so well done; service/repair proved, justified and resolved.

Projects like yours are always welcomed as we 1st worlders tend to forget that there are many others who do not have the benefit of spare part suppliers/ spare cash or technicians on hand to keep their equipment running. Many times we have had requests from areas such as the Pacific Rim and Middle/Far East asking about PCB component part repairs which we would not consider a worthwhile repair especially has we aren't privy to the electrical schematics of the OEMs. However there are many talented people out there who can/do and will perform these repairs at component level because that it what they have to do.

I have been amazed at some techs in places like Iraq who kept asking questions about AC faults while being shifted from town to town to get away from the war front. One day a picture of a blown motor capacitor and the next day a video of bombs going off in the next street. Nowhere near my kind of working day at all.

Your exercise demonstrates that these things are possible and therefore encourage others to press on, so thank you.

Sadly in this day and age of instant gratification via social media a lot of repairs are performed through the use of a smartphone and a certain amount of abuse, such is life.

frank
23-05-2021, 02:44 PM
And a great big WELL DONE from me. There is nothing more rewarding when, having carried out a sometimes, 'first time' repair, you re-apply the power and - bingo, it works, sort of moment.

I'm sure that all of us in one way or another, what ever our trade or speciality, have had that wry smile while standing back and admiring our handywork, that we didn't think ourselves capable of.

I can confess to having researched Youtube for knowledge on some non-fridge related repairs that I have then carried out with success and without having to spend a fortune on by engaging a specialist. (last time was re-setting the warning lights on the van dashboard due to it failing the MOT because the Service and diesel exhaust valve lights were showing)

I must admit though that I'm no expert in electronic pcb repairs. I have a basic understanding and have built simple circuits from scratch, changed dry capacitors (daughters piano power pcb) and replaced soldered relays etc. but more involved repairs are way beyond my remit. Finding replacement parts and having the proper test kit are other reasons why I just change boards ;)

Anyway, I'm pleased that you have had success and that your A/C is now back up and working. Time for a tinnie now I expect.

al
23-05-2021, 04:12 PM
Could we benefit from a right to repair law in all our countries, those shows on tv showing repairs / restoration be it of cars or family heirlooms are getting very popular! Well done again mate!

Tigercat
23-05-2021, 05:10 PM
Hey, thanks chaps, I appreciate your response.

Brian, the irony sir, what you wrote, concerning (let's say) 3rd world countries and their access to the spares/technology we are privy to. This was exactly on my mind when typing out my post (#71), wanted to mention it but thought I'd waffled too much. Spot-on mate, there are dudes in these countries/localities that repair just about everything, some under horrendous circumstances, as you mentioned. They really have no option (+ curious minds need to know), and I'm absolutely astounded at what they achieve, with the little they have...

Haha, I read you loud and clear Frank. Yeah, mate youtube has some excellent content from very helpful, smart people...they have helped me many times as well, haha, but not on this one, dang it.

Yes, Frank, good idea to replace your p/supply caps, good onya...you could apply that skill to other e'repairs, no probs. I use a good British Company (est~1920?), so you will have them there , called Radio Spares. They have good quality/range/products/spares (price is higher than local shops), excellent online catalogue. And even here, they deliver (free) the next day, as normally it costs + 7-10 days wait time. The local e'shop is also a great place but may be limited. Keep in mind, any mass produced brds use mass produced components...local e'shop first.

Tigercat
25-05-2021, 06:35 PM
OK, all done. Thank you to all, I was committed to complete, however, my motivation was maxed, due to the interest, comments, manuals and advice that you fellas provided...much appreciated.

A/C, is set at 23deg/c (will be 8d/c ovr/night) , vertical louvres on continuous....all good. Covers come up well with a good clean, as well.

As per photos, joined the drain hose pvc (cut to extnd d/hose) with some very old (all I had) "clear" tubing (works well), electronics bay without cover, e/bay cover installed + bare complete unit, completed with cover + installed new purifying, deodorising filters.

In photo #3, this cct brd contains the power supply (Lo dc - cntrl cct +Hi dc for blower) and control (processor, transducer sense, stepper mtr drive, system protection ..blah, blah....). The blower mtr has its own control brd inside the mtr housing but takes instructions from the main processor, and also provides feedback from the motor: temperature, position, rotational speed etc.

So, it's goodnight from me and goodnight from him...Tiger(Ronnie)cat

Brian_UK
25-05-2021, 07:27 PM
A gentle ripple of applause was heard from around the forum.

If anyone wants to award him some rep points it wouldn't be amiss.

Well done fella, here's to a warm winter for you.

al
25-05-2021, 08:17 PM
Done, what a thread:))