From this morings inspection… 2 heating and air units, both functioned well. The pictured unit was very hot, both on the fan exhaust air and on the actual unit housing. 9:00 AM inspection only 89 degrees and the other unit was in the 90’s temp wise. The pictured unit was 127… Thoughts, comments… problem, no problem and lastly what would cause it to run this hot…


If that compressor is runing low on freon and about to go into a thermal overload or is in overload you might not know if you don’t put gauges on it.


What is thermal overload?

I wouldn’t worry about a temp like that. Was the suction line cold? The temperature you read could be easily be generated by a unit under load working normally. Was the coil dirty?

Here is a T and P chart

T and P Chart.jpg

I worked on a AC the other day it looked like the line was sweating and cool. However it was really hot out the line was really trying to freeze up because the compressor was out.

What causes high discharge air temp from a condenser?

Reduced air flow. Dirty coil (even if it looks clean, it’s dirty).

What should the temp split be on a condenser?

There are a bunch of “temp-split” guys out there.
30 degree delta T ?

Why is the motor heating up?

Your trying to cool it with 127 degree air.

I think there is something to worry about with a 37 degree temp split between the two units. One of them are off.

If you didn’t use an IR Thermometer, you would likely find the temps even higher! I think what you are seeing with the IR thermometer is a good indication that this needs to be serviced.

I would never use an IR to take a temp from a condenser. A stick thermometer or a digital thermister is the way to go. We can’t be sure 127 is the true temp he was reading. We really can’t troubleshoot the system from our computer chairs. :slight_smile: We don’t have enough info.
If I had suction and discharge pressures, temp readings from liquid and suction lines, indoor and outdoor ambient temps I could.