catsoup
29-04-2017, 02:55 PM
Hi all,
I am an amateur doing this with limited equipment, so sorry if I cant give exact pressures/temperatures etc.
I replaced the compressor in an R600a electrolux ERN2920. Have tested all the joints with pressure, no bubbles in the soap, and vacuumed the system, and it holds the vacuum for over an hour without any sign of leaks.
I vacuumed it out for 2 hours, weighed in the 74g of R600a and the evaporator cooled to -20 degrees. I assumed all was good, but 20mins later it started warming. The compressor was still running okay. The discharge from the compressor had gone from hot to tepid.
Suspecting moisture (I don't have Nitrogen to purge it) I vacuumed it out for 10 hours. (I don't have a way to measure the level of vacuum). I also warmed the various parts with a hairdryer as that seemed a good idea at the time. (But was probably pointless!) I recharged it, and got the same result. ie. It cools well, then after 20-40mins it stops cooling, and the discharge pipe goes from hot to tepid. This time I measured the suction tube pressure throughout the test. It remained at around 8psi when working and after it had stopped working.
I still suspect moisture possibly jamming the compressor valves? But that seems a random event, where this I can reliably reproduce on every test. It works for a while, so I am thinking that its not a full blockage, so maybe moisture is forming ice and is blocking the cap tube? I have not replaced the drier filter, but since it works for a while how can that be the issue. Its also awkward to get at and shield from the torch. I still suspect moisture forming ice, but before forking out 50 quid on nitrogen I though I would ask the experts!
I have argon gas, and I let that run through the system when changing the compressor, no oil or other muck came out. I let it bubble into water. The water was clean after. The flow was steady.
Any help is appreciated :)
Chris.
I am an amateur doing this with limited equipment, so sorry if I cant give exact pressures/temperatures etc.
I replaced the compressor in an R600a electrolux ERN2920. Have tested all the joints with pressure, no bubbles in the soap, and vacuumed the system, and it holds the vacuum for over an hour without any sign of leaks.
I vacuumed it out for 2 hours, weighed in the 74g of R600a and the evaporator cooled to -20 degrees. I assumed all was good, but 20mins later it started warming. The compressor was still running okay. The discharge from the compressor had gone from hot to tepid.
Suspecting moisture (I don't have Nitrogen to purge it) I vacuumed it out for 10 hours. (I don't have a way to measure the level of vacuum). I also warmed the various parts with a hairdryer as that seemed a good idea at the time. (But was probably pointless!) I recharged it, and got the same result. ie. It cools well, then after 20-40mins it stops cooling, and the discharge pipe goes from hot to tepid. This time I measured the suction tube pressure throughout the test. It remained at around 8psi when working and after it had stopped working.
I still suspect moisture possibly jamming the compressor valves? But that seems a random event, where this I can reliably reproduce on every test. It works for a while, so I am thinking that its not a full blockage, so maybe moisture is forming ice and is blocking the cap tube? I have not replaced the drier filter, but since it works for a while how can that be the issue. Its also awkward to get at and shield from the torch. I still suspect moisture forming ice, but before forking out 50 quid on nitrogen I though I would ask the experts!
I have argon gas, and I let that run through the system when changing the compressor, no oil or other muck came out. I let it bubble into water. The water was clean after. The flow was steady.
Any help is appreciated :)
Chris.