: > > i recently had to have the condensing unit changed out, in my home. : > > the unit is a 3 ton 13 seer amana condenser. i don't know what the : > > evaporator brand is, but it's about a 10 seer with the same tonnage. CY: Matched for tonnage is good.
: > > The amana unit is only about 2 months old, but when it runs, sometimes : > > it squeals, sometimes the fan does not come on, and sometimes it acts : > > like it's straining to compress the refrigerant. it acted fine, for : > > about a month, then, one day, i walked outside, the compressor was : > > running, but the cooling fan was off, and the compressor was : > > squealing. ever since then, it exhibits the signs above. CY: Something seriously wrong. On most AC, the fan should come on at the same time as the compressor.
i had an a/c : > > tech come out and look at the unit. he advised that the condenser is : > > too inefficient for the evaporator, and the refrigerant is reaching : > > the compressor in a liquid state. CY: A new outdoor unit would have a new condensor, which is as efficient as you're gonna get. Makes me wonder if the indoor unit is a problem. That could cause liquid to flood back to the compressor.
: >
: > > now, i know the basics of how refrigeration works, but i'm no expert, : > > although, i'm a quick study.i do build computers, so i know how to : > > read a wiring schematic. i noticed that the condenser has a
2 speed : > > fan, so i had him buy pass the low speed, to make sure that it wasn't : > > the speed switch. so far, i have not noticed the compressor running : > > with the fan off, but it has only been a day. CY: yes, the outdoor fan should run with the compressor.
: >
: > > does the guy's theory about liquid refrigerant reaching the compressor : > > hold "liquid refrigerant" he didn't take any pressure readings from : > > the lines. CY: It's possible. If there is liquid coming back to the compressor, it sounds like your indoor evaporator is dirty, or low air flow. Or both.
: >
: > i just spoke to someone regarding this issue, that i know i can trust. : > he advised that if the evaporator were not vaporizing the refrigerant, : > the compressor would be making a chattering sound, from the valves, : > not a squealing sound. he seems to think that it overheated or it is : > not getting oiled properly. CY: I'm with you on the evaporator part. As to not oiled, well, the oil is mixed in with the freon.
: >
: > the ac tech is trying to say that because the condenser is seer 13 and : > the evaporator is seer 10, it is causing problems with the compressor : > by not allowing the refrigerant to vaporize. CY: Or, the old evaporator may be totally dirty.
: >
: > as far as i know, seer is just a measurement of efficiency, not a : > measurement of btu or tonnage, and would not have the same effect as : > putting a 4 ton condenser on a 3 ton evaporator, for example. am i : > correct in assuming this? CY: I've heard that it's not good to put a high seer condensor on an older evaporator. Sounds like one of those cases.
: >
: > my condenser and evaporator are both 3 ton units. CY: Best of luck. Let us know how things work out. :