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nic0
17-11-2004, 11:30 AM
Hi this is my first post, I only descoverd your forum tonight.

I managed to put a small hole in the aluminium evaporator in my 120 litre bar fridge. A replacement evaporator costs about the same price as the fridge AUS$300.

If I replace the aluminium evaporator with one made out of 1/4 inch copper piping and silver soldered the suction line to one end and the capillary line to the other, would it work and how long would the pipe have to be? I have seen pictures of homemade keg coolers that have sprial copper evaporators.

The fridge is a fisher & paykel P120 which has a matsu****a compressor and had 60 grams of R134a in it.

Thanks
Nico

Brian_UK
17-11-2004, 01:57 PM
Hi Nico and welcome.

Two things spring to mind.... I'm not sure about usingbare copper inside a fridge, possible food contamination problems (I'm prepared to be shot down over that comment but...)

It is possible to purchase evaporator leak sealer for use on fridge evaporators, it may well be worthwhile investigating that first.

chemi-cool
17-11-2004, 03:56 PM
Hi nic0,

Welcome.
It is not a problem to fix the hole if you have any experiance in aluminium welding.
If not, just get a new one or second hand.

Brian, no problems, you are wrong :D

Chemi :)

coolkev
17-11-2004, 06:25 PM
:cool: No probs at all done many of them over the yrs I always put as much as can phsically fit the hardest part is getting both ends to end up in back corner i saddle to old evap with full cu saddles and pop rivet from inside evap put cu tube and saddles on exterior charge to frost line . Has always worked fine also works on chest freezers but i use 3/8 tube

coolkev
17-11-2004, 06:30 PM
:cool: 1/4 cu tube on bar refs 3/8 on freezers 1/2 on really big freezers

nic0
18-11-2004, 12:33 AM
Thanks for the replys, the fridge is only going to be used for beer so there will be no problems with food contamination. Kev the fridge I have has the capillary tube inside the suction line and it's separated by channels on the evaporator. I haven't ripped the back off the frigde yet to see at what stage the capillary tube enters the suction line. Do you separate those lines on the outside of the fridge or on the inside. (pictures of some of your mods would be nice)

I was thinking about using T pieces and reduction fittings to separate them.

Can you still buy R134a without a license in Australia, the refrigeration guys are charging outrageous prices here in Brisbane for a regas.

eggs
18-11-2004, 01:35 AM
MATSU****A, i just bought a new matsu****a telly today.
i wonder why they call it Panasonic in the UK ?
ps, if anyone is in the manchester area, can they come and wire the thing up ?
speakers, dvd, video, ps2, digi box, dodgy free porn ( i mean sport)cable box thing, normal arial, i give up. it's got more interconnecting wires than a cheap chinese (gree, chigo etc) a/c system

cheers

eggs

that there A/C stuff they knock out isn't bad

cheers

eggs

RogGoetsch
18-11-2004, 02:57 AM
It is possible to purchase evaporator leak sealer for use on fridge evaporators, it may well be worthwhile investigating that first.

I agree. I generally avoid the stuff like the plague, but had a customer decline to fix a small office fridge when I quoted him time and material for a proper repair. I offered to take the fridge in payment for the service call, epoxied the hole with the proper epoxy designed for fridge repair.

That was about 8 years ago. It has been doing just fine in my office until last month, when the evap started to frost only partially. I don't want it pulling into vacuum, so have pulled the plug until I can check out the size of the leak.

Welcome, and good luck.

Rog

nic0
18-11-2004, 03:16 AM
It's only a small hole so I will see if I can get some.

Thanks

coolkev
18-11-2004, 12:56 PM
:cool: once you pull the copper out of the alum. i split the suction line for about an inch pull capp. down split squeeze split back together silver solder up when suction end of evap fitted.Then solder capp in feed end no drama. Have used several different epoxies with mixed results, found green stick most sucessful must be very clean no oil at all. CU wrap 100% never fails.

nic0
19-11-2004, 07:53 AM
Well I got some of that leak seal stuff today, it says on the package that it can handle up to 4000 PSI. I also priced a basic system and I can get manifold gauges + hoses, gas bottle + 5kg of r134a for under AUS $500, which is tempting cosidering some people were going to charge over $300 to fix the fridge.

chemi-cool
19-11-2004, 01:31 PM
Hi nic0,

I hope you never go into business because you will lose all your money before you start.

Lets work it out from your point of view,
All the parts you will buy will cost you under $500. You will also need a vacuum pump, a welding torch, silver rods and a drier.

That will add how much?

Repairing will cost you $300.
If you are going into business, never work for free! It will cost you!

Unless you have some spare money or want to make an experiment.

Chemi

Peter_1
21-11-2004, 09:51 AM
He's still soooooo young and has to learn sooooooo much before he can go in the business,... no,... any business.
He forgets that the tech who comes to repair is doing his job so that there is bread on the table.

Are you working for free? Is your boss working for free?

Withstand 4000 psi??? I should say, give it a try man.
How will you apply the leak seal stuff anyway?

You don't need a new dryer in the system? And you don't need a torch for this.
After installing the dryer, will you vacuum it with your vacuum cleaner??

Are you licensed to do this?

You think you're a wise guy now but you're so far from that.

nic0
22-11-2004, 09:07 AM
I have no intention of going into bussiness, I am an electronics technician by trade and I was only thinking of getting into it as a hobby. What refrigeration cant be a hobby? have a look at some of the PC overclockers forums and homebrew forums. Vaccume pumps can be hired or a crude one built, and and a mapp gas torch works for brazing hobbie use anyway. You don't need a licence at this point in time to buy refrigerant in my state but that will be changing to.

Thanks for everyones help.

nic0
22-11-2004, 09:19 AM
Withstand 4000 psi??? I should say, give it a try man.
How will you apply the leak seal stuff anyway?


I don't believe everything written on a packet but thats what is written on it.

The stuff i used is called epox-a-leak made by wagner, I got it from the local refrigeration supplier, i was the only one they stocked. It works on all metals providing its prepaired properly, you apply it by getting the surface back to bear metal with emery cloth, clean the surface, then clean again with alcohol, mix up the epoxy and hardener in equal amounts, then apply with a spatula and let it cure for 8 hours at room temperature.



You think you're a wise guy now but you're so far from that.

Far from it. I am just trying to get advise from people in the industry.

Abe
22-11-2004, 09:49 PM
Whats up with these Aussies???

They cant spell
They cant write
They all want to DO IT Themselves!!!

Is something in Foster Lager or XXX that makes them like that ??

And to think at one time I was intrested about going to live there ?????

Abe
22-11-2004, 09:50 PM
Sorry

its XXXXX Castlemaine!!!

shogun7
23-11-2004, 12:05 AM
[QUOTE=Peter_1]
After installing the dryer, will you vacuum it with your vacuum cleaner??

I say Peter, can he really pull a hi vacuum AND clean it out with that. :D Now that was funny!

rick
23-11-2004, 11:58 AM
Whats up with these Aussies???

They cant spell
They cant write
They all want to DO IT Themselves!!!

Is something in Foster Lager or XXX that makes them like that ??

And to think at one time I was intrested about going to live there ?????

Ease up Aiyub.He was only INTERESTED in your opinion.

coolkev
23-11-2004, 12:28 PM
:cool: Aiyub two goes and still cant get it right XXXX and thats only in Queensland. Sounds like they wouldnt let you in.

Abe
24-11-2004, 07:51 AM
Hi Kev

True, I did have two go's and couldnt get it right!! Hic
Actually I lie..........Ive always dreamed of living in Australia..........if only the buggers would let me in !!!!!!
:)

Abe
24-11-2004, 07:53 AM
So its a bit of " sour grapes" on my part ........... :D

davey1000
26-08-2011, 10:13 PM
[QUOTE=Peter_1]
After installing the dryer, will you vacuum it with your vacuum cleaner??

I say Peter, can he really pull a hi vacuum AND clean it out with that. :D Now that was funny!

Nah he could vacuum it with his car! (a petrol engine that is in good condition can pull a pretty fair vacuum especially on the over-run) I've used this method to vacuum varnish impregnate electronic boards. The vacuum tank was an old Coughtrie of Glasgow exterior light fitting. In the case of electronic components, some will start gassing pretty quickly so you have to be quick. Diesel cars have little vacuum pumps built in but these are nowhere near as good as a petrol engine. By the way I do know about high vacuum, mercury vapour pumps and Bourdon gauges but for a rough job the petrol engine will do it OK especially if the system is double purged.

Brian_UK
26-08-2011, 11:13 PM
Thanks for resurrecting an old post.

As far as
but for a rough job, that's about all it ever will be.

install monkey
26-08-2011, 11:24 PM
least it wasnt hijacked by someone after a carrier service manual!!!