Re Gasing a fridge

W

wcarpenter

Member
Joined
16 Feb 2006
Messages
38
Location
Ireland East Coast
Visit site
I have a Danfoss compressor and evaporator unit fitted to fridge on my boat it runs ok but over the past 4 years the cooling has reduced to almost nil. I think the self sealing connection to the condencer is leaking. Can't find anybody locally who wants to repair, all very shy of boats. Doing some research i find kits for gasing air conditioning on cars available on line, right gas and gauges to give correct charge. There is a connection on the compressor so charging should be ok BUT I'm not sure of the connections on the kit sold for cars. Has anybody any experience that they could share with me? please.
 
Hi, car air-con systems use a quick-release coupling on the charge ports (they are all standardised) with different sizes for high side and low side ports. To re-gas your fridge, you really need 2 connections, high and low pressure (one on the suction side of the compressor and one on the high pressure liquid line after the condensor). you can get self-piercing, clamp-on charge ports for copper tube which will allow connection to the system. Most refrigeration systems use standard components, so obtaining parts is fairly easy. Try SRW, they have a good website and mailorder service.

Peter
 
Thanks Peter I thought I could just connect to connection on compressor and run, so the compressor would draw in gas from upright cylinder, the charge is only 60 grammes which seems quite small.
 
Get a professional to do it it's NOT a DIY job if you have not had any training or do not know what you are doing. I have worked on most types of them and AC for over the last 50+ years one way or another. Refrigerant in a confined space is very dangerous to your health. An absolute must is DO NOT smoke or any naked flames. It is not inflammable but when exposed to a flame most if not all refrigerants produce phosgene and that is highly toxic. Mind you we used to use a special adaptor to a gas lamp to search for leak's in the 60s / 70s possibly some Eng's still do. A car chap should be able to do it for you. If you have to go down the line of DIY then read up properly get a good book on refrigeration from the library also contact the manufactures for a service manual if they have one. "Kempe's Engineers Year-Book" is a good one mine is a 1983 copy and section B4 will explain most of it to you.
Just an addition can you remove the whole unit "as one" from you boat and get it on a workbench that will make the job a lot easier .
Cheers and I hope this helps.
 
Just continueing on from Old salt it may be possible (surely possible) to remove the whole system by disconnecting the quick connects. Any fridge mechanic shop shouold be able to do the service in their own workshop. This should include service of the quick connects if that is where the leak is.
It might be practical/possible to pressurise the system with air to check for leaks using detergent before removal so you can identify what needs fixing before regass.
Of course if you get a man to do it in situ you might like to eliminate the quick connects if they are doubtful.
I think you will find if you have a leak and especially if you open the system that you will need a vaccuum pump to evacuate the system before regassing.
good luck olewill
 
Are you sure that is the cause? We had the same symptonsa few years ago and worke dout it HAD to be the gass! When I 'got a man in' to re-gass he found that the thermostat that was faulty - replaced that and everything has been fine since.
 
Thanks, I tried with the stat at max and min BUT if the stat was gone then it could fool me!! my next job is to bypass the stat. Your lucky to get a fridge man to do your boat, I can't get one, to busy with big air conditioning jobs.
 
If the compressor is running the stat is making so no need to by pass it and if the stat had failed to open on cooling the evaporator would be all iced up, Is there 'any icing' on the evaporator (ice box tray). There are basically two things that can be wrong the compressor is not compressing ( if it is a sealed unit replace with a new one is the only way), or it is just short of gas, short of gas is my bet. I personally would not introduce air in to the system air contains moisture and that is a 'no' 'no' in the system you would have to evacuate with a separate vac rig and dryers. There is no doubt the best route to go is to remove the whole unit from the boat. Then in an open space workshop or garage (not outside the open air will let any escapes simply blow away) do a leak test with a test lamp or electronic sniffer is no problem. There probably wont be enough gas to do a bubble test with soppy water, not a good thing to use any way as there is the proper stuff for doing it. If you have a friendly refrigeration engineers local to you try to go and have a chat with them some will talk, some still think its a magic art. As I have said a trip to your library may be worthwhile.
 
You must log in or register to reply here.

Share this page

Top