At my inspection today I advised my client that I couldn’t start the A/C because of the temperature outside.
He had a large freezer running in the garage and wondered why the freezer operated quite well at low temperature but the A/C could not. It was an unheated attached garage and the temperature, while somewhat above ambient, was still close to the freezing mark. The freezer had been in the garage for several years.
Does anyone know why you can operate freezers in cold temperatures but not A/C?
I believe the freezer is ok because it was running before temperature drop, and was not idle. The A/C is not running so the oil settles in the compressor. Then you start it up and no oil on parts that need it. I suspect you could run the A/C at low temperature if you had it on before it got cold and just left it run. i could be wrong or just not explaining it correctly, but that has always been my logic. Hope that helps. Anyone correct me if I am wrong.
That makes perfect sense. A heat pump which as we all know is an AC that goes both ways:) ] has a sump heater to keep it’s juices flowing in the winter. Now if he turns off his freezer and the compressor oil freezes that is another story…
Also you have to take into consideration that the freezer should be insulated keeping the cold in and apparently the cold out also, so that combined with the fact that it has been running, everything should be ok, hope he doesnt get a blown fuse or power outage for too long of a time…
Guys we need some serious refigeration training here.
Oil in the compressor does not freeze
The major concern about an A/C unit in low ambient temps without crank case heaters is the fact that Freon Migrates to the coldest area of the system which happens to be the compressor where the oil is stored. When you start the compressor that has liquid freon mixed with the oil, the liquid freon can and will damage the valves in the compressor and will also cause the oil to pump out of the compressor. I can go on and on about this but am trying to keep it simple.
BTW refrigerators only have oz.s of freon V/S pounds in a A/C unit and do not have liquid migration as they are not a split system. There has to be two areas with different temps in order to have liquid migration.
I live in a cold area and my freezer is in my garage .
My garage is insulated and has never gone below freezing it is fastened to the home . -20 F and the garage is at 34.
I talked to a repair mechanic and he said the efficiency on the freezer goes down but it does no seem to effect the operation.
Mine is only 20 years and works well .
Well they remove heat from the air right, so maybe there is something to them running all the time.
Kinda like a running car with no battery.
Ok till you turn it off.
Charley, thank you for a better explanation, I was not saying that oil freezes. I said that I may not be explaining it perfectly, just easiest way for me without getting all technical. good post.
OK Scott here is lesson one.