AC Servicing & Cleaning Questions!

Hi All,

Novice here so apologise in advance for my ignorance on AC matters!

I have a Fujitsu ARY14ELA/AOY14EMA AC System that uses R407C & feeds into my upstairs bedroom. The system was fitted about 7 years ago. It is a Ducted system that has 3 diffusers in my bedroom ceiling with the ducting & metal box in the attic which is connected to a Compressor/Condenser fixed to an exterior wall of the house.

Although it has honestly been lightly used, it has never broken down or had any issues - still works to this day but I noticed it kind of struggled to cool the room down as quickly as it used when we had a few really hot days recently. When the temps are not so hot, it seems to cool normally.

Another issue I have had is that my room get covered with dust extremely quickly - it drives me absolutely insane - one can clean the room spotlessly & the next day, a dust layer has already formed on everything - I have no idea why it gets so very dusty so quickly. This happens even if I close off the diffuser vanes.

I have to be honest here - my AC has not been serviced or cleaned in the years that I have had it & I am wondering if this might be a reason why it seemed to struggle to cool down as quickly as it used to when during very hot temps? Could my room dust problem also be down to the system possibly needing a clean?

If a service & clean is warranted & needed:

1) What sort of costs am I looking at with the sort of system I have?

2) How can I ensure I get a honest & qualified person to do things properly & not some cowboy posing as a pro as I know no-one in the industry - sadly the guy who fitted it is no longer around.

3) How would I know if he has done all things needed - is there some sort of list/reference that one can refer to for AC servicing/cleaning so that I ask them about & tick off? I just do not want be at the mercy of their word due to bad experiences with unfamiliar workmen in the past!

4) The ducts in my loft are the flexible silver ones - there are 3 of them - would they have accumulated dust & stuff inside & would they need cleaning & would that be done as part of the service?

5) I guess my system is pretty old by today's standards but how much worse it is in terms of energy use & cost to operate compared to newer ones?

Very sorry to ask so many questions & for the long post but am hoping to educate myself on the matter & not get ripped off as well so would dearly appreciate any help & advice!

Many Thanks,
Bazzy!

Where abouts do you live bazzy? I'm sure someone on here could do you a full service and F-gas checks.

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Originally Posted by Airconking

Where abouts do you live bazzy? I'm sure someone on here could do you a full service and F-gas checks.

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Hi!

I live in NW London - any idea as to what might be involved in any servicing/cleaning etc & what sort of costs I can expect?

In an effort to learn, I've been watching vids on Youtube but there is almost nothing regarding cleaning/servicing ducted systems in the UK that I can find! Also, very little if anything regarding the Outside type of condensers we have in the UK - nearly all are from the USA that have those big floor based square ones which I have never seen here!

Just wanted to also add (as I forgot to mention it earlier), is that I usually always have at least one of my bedroom windows open most of the time to let in fresh air. Whether this might be the major culprit to my dust problem, I do not know but if I close the windows for any considerable length of time, then there is a sort of damp, stale smell that takes over the room - just thought I would mention this in case it might be important & provide some cues!

Many Thanks,
Bazzy!

The unit air filter is probably in need of cleaning as it sounds as though the air flow is reduced.

You have three supply terminals, is there a ducted return grille or does the unit just suck air from the loft?

for your own health reasons get a service done on system, that dust everywhere is not good, can contain all sorts of nasty's including legoinella spores that you breath

I would suggest you just need to clean the return air filter on the back of the unit. If you can access the unit then you should be able to access the filter which can be cleaned with mild detergent etc.

Can you attach any pictures/video upload to youtube showing us the system you have and subsequent ducting in your loft. This would give us a really good idea of what you have on site. The first thing I would do which you can do yourself is to clean the return air filter. I assume one of the diffusers is a return (takes air back to the indoor unit in the loft to be cooled again) the others will be supply (brings air into the room).

The fact you say your room is very dusty indicates the unit is possible bringing that return air from the loft itself rather than your bedroom. The loft can reach sometimes 40/50C when it is hot outside which would indicate also why it is struggling to cool. A dusty room could be down to outside dust coming in but this would affect all rooms if you have doors/windows open.

Several possible reasons:

1. Simply the return air filter is blocked... most likely cause given that you've not cleaned this in 7 years.
2. Return air duct has become disconnected from the unit causing air to be sucked from the loft and in turn dusty air from the loft. There might not even be a return air duct connected which again is unlikely but has been known when contractors cut corners - again would indicate why your room is so dusty. This would in turn cause the evaporator coil to become clogged with fine dust that gets past the ordinary filter and the clog.
3. Unit is short of gas due to leak (unlikely)

Best thing to do is try get some pics taken or a video to youtube showing us your system. Try to clean the filter yourself which should be done every 6 months or more depending on how you use your unit or the location of it etc.

If the system has not been maintained (cleaned) in so many years, it is likely that the main air filter in the loft unit has become mega clogged up and the dirt is obstructing air passage through the filter/unit/ductwork/diffusers. Consequently, less air is leaving the diffusers and thus there less performance showing in the room. Cleaning that main filter would be the barest minimum and if you are up to a trip into the loft you might be able to do that yourself after a quick look at the manual to see how to release the filter (if no manual, get the model number off the loft unit and search internet).

One thing about a loaded filter is that the pressure of the fan will push the dirt through the filter after a while and the dirt will find its way into the heat exchanger, onto the fan unit, and into the silver ducting, and grilles, and some of it will then get blown into the room, settling on your nice clean surfaces. The sleepers will also inhale this dirty dust while they sleep (yuk!).

As it has been so long since it was installed without any cleaning since then, I would replace the dirty silver ducting with new, which is the best way to clean that stuff. And when you contact a maintenance engineer tell him about the lack of past maintenance and ask him what tasks he would do on the loft unit. To many, the answer would be to take out the filter and brush it out. Some would also wash it with anti-bacterial cleaner too. They might even put a dab of Smelly Jelly in the unit to give you a nice fresh smell after they are done -- but that just masks any smells btw - no actual cleaning. There are tablets that can go in the drain pan to deal with nasty bacteria that can collect there, which is quite valid.

Ideally you would get someone to open up the unit and clean the heat exchanger (might need blowing through with nitrogen to get it all out from between the fins) and to clean that fan wheel and inside the casing (box). That should deal with all the dirt and dust inside the unit. Also replace the silver ducting as that is not sensible to try and clean it. But if go with such an engineer, actually watch him do the work to be sure it does get fully done. The salesman might say one thing - the engineer might do something less.

I think it's a bit extreme to go replacing ducting, get the filters cleaned and if there's any smells coming from the unit then clean heat exchanger. You can do this yourself by spraying it with a disinfectant spray from a spray pressure bottle. Very easy to do. Then put the unit into full cooling for a few hours and it's self rinsing.

You can buy bleach tablets from the pound shop type places, pop a couple of these either side of the drain pan etc. The dissolve slowly over time in the condensate pan and keep it all clean.

I bow to your greater knowledge.

Do you really think the work order to change the ducting with new when the filters haven't even been cleaned? You might as well say the same for any other system even if the filters have been cleaned. Good advice I just don't agree with the ducting replacement. There's no need to.

Same kind of row I have with some engineers when I tell them what to do.

The flexes are obviously full of dirt, as the dirt is also in the room. The customer wants to fully handle the dirt so fully handle it.

The plan is to do it once and do it properly. Then no call-backs and fast payment. The customer is happy and will remember that you do a good job.

And the engineer can get off to the next install without a callback.

Why send an engineer twice to the site when he could replace the ducting while doing the other maintenance in one visit? Cost of ducting is about £50. A visit much more.

If the engineer needs to go a second time to sort the flex ducting, you also have a complaint from the customer that the first phase was not a good result, which is no good either.

Engineer should take of ducting if needed and clean out. The op stated it was a dusty room rather than grit and other dirt. Once system is back up and running and cleaned out any dust should reduce as it will escape out the ducting, I know my preference would be to put up with a dusty room for a few days after cleaning than waste the ducting.

I see you thinking though but we don't know how much dirt is in the thing yet. It's likely just a blocked filter and op says unit has been lightly used.

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Originally Posted by back2space

I think it's a bit extreme to go replacing ducting, get the filters cleaned and if there's any smells coming from the unit then clean heat exchanger. You can do this yourself by spraying it with a disinfectant spray from a spray pressure bottle. Very easy to do. Then put the unit into full cooling for a few hours and it's self rinsing.

You can buy bleach tablets from the pound shop type places, pop a couple of these either side of the drain pan etc. The dissolve slowly over time in the condensate pan and keep it all clean.

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That might work on your wall-mounts but simply spraying cleaner into a void unit won't cut the mustard, you can't see the coil for a start.

The drain pan is inside the unit so dropping a couple of tabs in isn't feasible.

Also the cost of the flexible ductwork may well be cheaper than trying to clean it.

Hi All,

Apologies for the delay in responding & thank you kindly for all the helpful responses so far - reading them has given me some encouragement that if I can find out where the areas are, I might be then be able to clean them out easily myself as has been stated!

Fujitsu sent me over a sort of users manual (not a technical/installers one) & there is no mention whatsoever on how to clean the unit(s) or even where the filters are located! I tried to upload it here but sadly the system says it is too big.

I am almost certain the installer at the time stated that one of the 3 vents in my room was a "Return Flow" but I am not sure exactly which one - I have a feeling it might be the one nearest the corner on the window side of the room but would need to make sure somehow - how can I tell?

I went up in the loft today & took a bunch of pics as requested to show what is up there & how it is all arranged (sincere apologies for the bad state up there!) - hopefully this will help identify which might be the "Return Flow" & where the Filters were located so that I can access & clean them as well as the Drain Pan mentioned so I can get those tablets to place within - where are they located?

It seems the installer covered the whole unit in a thick foil type padded insulation - it looks to be in good shape to the eyes of a novice but hopefully you all can confirm - would this have to be removed to access the Filters/Drain Pan? Just want to ensure I will be able to place it all back properly if needed & if It is advisable for me to do so?

One more guilty admission on my part - a couple of years ago I noticed that one of the ducts had sort of partially been ripped at it's sprocket(?) connection so at the time, I sort of pushed it back up as best I could & taped it up with duct tape as best I could - very sorry to have omitted to mention this as I had forgotten myself & only remembered today when I went up to take pics - how bad is this & is it easily solved?

From the unit in the loft there are about 3 lines - two padded black ones & a single white plastic one that run from the side of the unit to the back of the roof line & then across one side of the loft floor, then takes a small turn at the corner and then exits out via the eaves/soffits to the exterior. They then run down an exterior wall about 2m to the outside condenser unit which is located on an exterior wall above a conservatory roof.

I read on the Fujitsu website that if properly installed & assuming no leaks, then the system will never need any re-gassing or topping off - is this true? If so, that would be a very good thing from my side!

I would like to also ask however, what does one have to do to the Outside unit to keep it in good shape? I see videos on You-Tube (admittedly USA ones) where they spray this foaming cleaner into the coils that gets all the gunk & dirt out very impressively but there is very little info out there on there on how to clean/service the type of wall units we have in the UK. I do not know if it would be a good idea for me to mess with the outside unit unless I had very clear instructions on what exactly to do in case I cause any issues but I am assuming that the outside unit also might need some attention/cleaning?

As regards the actual ducts themselves, what & how is the normal procedure for cleaning them & would it be something I might be able to attempt before considering any heavy cost of replacing them by an engineer?

Due to upload limits, I have posted the pics on Photo-Bucket - please kindly see:

http://s296.photobucket.com/user/Baz...20Conditioning

Once again, sorry for the long post!

Bazzy!

It looks to me that the duct that you taped back is the return air duct.

There should be an air filter within the metal box that thry fitted to accept that duct. No guarantees though.

You need to see if there is either an access panel of some sort or some means of removing the duct box.

Perhaps to start with, take off the duct and have a look inside the box.

In an ideal world there should be an access panel but I have known installers in the past who simply rivet the box on with no regards to later msintenance.

You do know the maximum length of a flexible ductwork section should be around 500mm right?

Flexible ductwork has a huge pressure drop as opposed to solid ductwork...your 4kw Fujitsu is probably only achieving 2.5kw.

Circular diffusers also look undersized as I know you always have to go up a size or 2 from your ductwork size to achieve the correct air volume.

Back2space - good luck in trying to clean flexible ductwork!

Quote:

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Originally Posted by Slim R410a

You do know the maximum length of a flexible ductwork section should be around 500mm right?

Flexible ductwork has a huge pressure drop as opposed to solid ductwork...your 4kw Fujitsu is probably only achieving 2.5kw.

Circular diffusers also look undersized as I know you always have to go up a size or 2 from your ductwork size to achieve the correct air volume.

Back2space - good luck in trying to clean flexible ductwork!

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I don't see why ductwork would need cleaning at this stage, best to check that the filter is not blocked. If its blocked then less and less air will have gotten through. If no filter has been fitted then it will be the coil that has "filtered" the incoming air. IN a residential setting its not likely that the ductwork is that dirty. Indeed a unit in our building here - the filter had dropped off and was laid on the suspended ceiling. The unit was difficult to get to until I took over the building and has prob run like this 16 hours a day. The coil needed cleaning but all associated flexi ductwork was clean and not dirty. Even supply grills were clean apart from on the outside where the supply air met room air. The coil was however filthy.

If you then inspect supply ductwork and it is dirty then clean replace whatever suites. The return air is the ductwork that has been taped back on, inside that box is the filter. This is what needs cleaning. I expect on a domestic property cleaning the filter should be enough. Once that unit is up and running again and condensate produced will probably rinse the coil. It also appears from the pics that the vent by the opening part of the window is the return grill as this looks dirtier than the other two.

How have you got on op?