Hello ( re: R22contamination ) I have a TRANE XR12 3.5 Ton R22 Condensor that was shipped with dry gas in it. My installer thought it was charged with FREON. It caused high pressure on the load side to 350lbs..after determining this error he evacuated the system and re-charged the unit with new R22 Freon... ( he did not read the sticker stating it had DRY GAS installed next to pipe ) NOW, the unit is "some what" working. It does not get colder than 75. It was 90 degrees yesterday and it took 5-6 hours that first night to get down to 76..Yesterday I tried to get it down to 72 to check it out and it NEVER got below 75 even at night when it went down to 80 degrees outside. The airflow and meter readings he did seemed perfect, ( 225 lbs and 40 degrees - he stated ) BUT the pipe is NOT cold and NOT sweating outside. The coil is NOT iced over and the inside pipe is NOT cold and icey... My other unit is sweating and cold ? Is it still contaminated ?? I am not comfortable that this unit is working ? All input is apprectiated. ( he is willing to come back, what else can we suggest?) Thanks KMH

I had two new American Standard systems installed last year, 5 ton downstairs and 3 ton upstairs, both with 2-step Scroll compressors and variable speed air handlers. The downstairs air handler is a communicating model (though it's set up for normal 24v control), while the upstairs air handler is not. Incidentally, after noticing very low airflow upstairs when on stage 1, I did some research here on this forum and discovered that it had not been wired properly (was using Y LO and Y instead of Y and BK). The installer came back and fixed it. After that was fixed, we did have some problems with humidity upstairs, which the installer improved by setting a slower fan speed and also by turning off Comfort-R (the early part of the Comfort-R profile was helpful, but the fan-off delay at the end of the cooling cycle was putting a lot of the humidity right back into the space). However, I've just discovered that there is still an fan-off delay. After the call for cooling is satisfied, the blower continues to run (at the same speed) for exactly 60 seconds. That alone seems pretty odd, as the documentation doesn't even list that as an option (1.5min/100% and 3min/50%, along with Comfort-R). I've confirmed that S4-1 and S4-2 are off, which should result in no cooling off delay, right? I will have the installer come back out and have a look, but before I waste his time, I just wanted to make sure that this wasn't normal behavior, even if it's contrary to what the manual seems to indicate. Thanks!