R600 compressor running into a vacuum
I have been running into a issues with R600 freezer running into vacuum after fixing leak. I didn't want to condem the compressor yet. Initially I thought it was a restriction. So I flushed system with nitrogen. I had good flow on my suction line. However after pulling vacuum to 500 microns. Charging by scale. My chest freezer would run and cool to desired temp. But then it goes in to a complete vacuum then stops cooling amps drops as well significantly. No heat rejection. Compressor just runs. When I turn it off it equalize back to normal so no leaks. When I turn it on again. It does the same thing. It can't be undercharged as I charged by weight.
Is this a good question?
Score
0
6 
4 
2 
@aluikpoate What is the brand of the freezer? I assume that "R600" is your model number.
by Theo Grefalda
@user5136121
R600 is a type of refrigerant used in cooling systems.
Supersedes R134, R12 etc
by jayeff
Hi @aluikpoate
Knowing the make and model of the freezer would help.
Is there a filter/dryer in the line?
by jayeff
Yes, year, make, model? R600 is isobutane, used as refrigerant but you're not providing detailed info. Is this is the first repair, presuming you attached fittings to a factory sealed refrigeration system, Flushing with nitrogen may not do anything if the system never leaked. As a general rule, once a system is opened, the receiver/filter/drier is replaced when a compressor is replaced. If two service valves are attached, then you can monitor low and high side for proper pressures. Years of reliable use can generate debris. The receiver/filter/drier serves four(4) functions, the last being the tiny capillary tubing, separating the high pressure side from the low side, releasing liquid refrigerant into the evaporator coils to remove heat as r600 expands back to its gaseous state. While only a guess, this may be the problem if r/f/d becomes blocked from debris.
by F Dryer
Thanks for the response guys. It's actually for a chest freezer fisher and Paykel model number RC719W2. Yes this is the first repair. Compressor gave out due to the condensor fan not working. I replaced the fan, compressor and filter drier. Flushed the discharged line. Installed the drier. Then flushed the suction. Brazed on all the fittings. Leak tested all the joints and left it under pressure. I pulled a vacuum after to around 500microns. Then I scale charged to 110 grams R600a. Because I work on bigger systems. Was trying to see if I missed a step. The drier I installed did not have a service port so it was brazed on directly. Also note the system did not have a leak. Just the compressor giving out. Original compressor was changed like for like. When it was pulling down temp my compressor was around 0.68amps with a suction of -5inhg. As the box got colder the amps dropped and closer it got to -23 the closer it pulled towards. -15ingh. When I woke up in the morning it was in a full vacuum with 0.4amps.
by Aluik Poate
Show 2 more comments