so what do you think, my AC was warm today, the suction line was icing up so I shut down the unit and left the fan on to thaw it out. checked the filters for restriction, they were clean. fired it back up after the unit thawed out and now my High pressure line is pretty cold and sweating, the suction line is near ambient temperature.
this is not a reverse cycle unit, electric heat strips, Builder grade Goodman 10 years old.
The compressor is noisy. and the condensing unit fan is pushing cool air as if it were in reverse cycle. could the expansion valve have stuck?
I have a service contract on it, but just curious if anyone has any ideas.
Thanks Bruce, thought about it this am with a fresh head, has to be a restriction causing the pressure drop, The line is sweating all the way to the unit, I will have to look for a change in the temp of the line to indicate where the restriction is.
so the tech was out this morning. low side pressures were 35 high side just over 100. ambient temp today was around 73. The unit was showing about 5-8 degrees of temperature differential. Still cool liquid line and the condenser fan was pushing cool air.
The tech pushed refrigerant into the system and the low side came up to 55 or so and the high side only reached about 120.
He is going to throw a compressor on the unit. (filter, capacitor, fan motor as well)
Not really sure what his diagnosis was in the end, stated that the evap coil could be the cause for the compressor failure.
funny thing is he stated the year of the unit was 1995. House was built in 2000. I looked at the number on the unit, its a goodman first five are 00095. That of course makes it a 2000 model year unit 9th month. Not a 95
anyway we will see what the end result is. But I thought you all would benefit from the process
I recently had a similar problem, and for the reasons David mentioned, I opted for a complete new system (heat and air). The $1500.00 gov rebate did me no good (5 ton units were not part of the program :roll:). My monthly utility bills dropped so much I’m glad I chose to replace.
Ken, if you decide to replace, find a reputable installer. When I researched all the various brands, it all boiled down to how good your installer is.
This is just an experiment in diagnosis and repair. I have a service contract on this, no cost to me. I am certainly not comfortable with the diagnosis, but it will be interesting to see the outcome. So far 24 hours to get a tech for the diagnosis and he called today and scheduled the install for next Wednesday! Good thing I have another house around the corner or I would be putting my Wife and her dogs up at the Breakers for the week!
On the other note, its not due to lack of freon even though it did ice up at the evaporator. The key to this is that the liquid line was cold. That has to indicate either a restriction near the compressor allowing the liquid to transition to a gas prior to the expansion valve/orfice tube.
So just a final on this. They came out and dropped a new compressor, filter and condensing fan motor on the unit. fired it up and all was back to normal. The new compressor sounded quiet and smooth.
Never did I find out definitely what the cause was but I would guess it was valving in the compressor. So back to an 18 degree differential just in time for the cold weather.