I have a Rheem heat pump. I noticed cold air coming from my vents when the heat was on. I checked the outside unit and the fan was not on when it should be. I pressed the thermal reset on the unit and the fan started and ran for a few minutes before shutting off again. I know that there can be many reasons for the thermal to be tripped, what are some of them and what can I check myself. Any help would be appreciated - Thanks.

 

If you are talking about the button on the unit that looks like a pencil eraser, it is a pressure switch, not a temp switch, and sense I can't think of any other manual reset switches on a Rheem HP I will assume this is what you are talking about.

Make sure your filter is clean.

You haven't messed with the indoor blower speed or anything have you?

Nine times out of ten the reason for this switch to do this is low indoor air flow.

if that is not it then I would suggest calling a tech as it could be the switch is bad, or there is a problem in the refrigerant system.

How old is the unit?
Do you have a model #?

 

The model number is RPKA-024JAZ and it was manufactured in 1997. The filter is clean and I haven't changed any blower settings. I did have the unit serviced about 2 months ago and it was low on refrigerant but the tech stated then that he could not find a leak.

 

may be the reversing valve leaking by.

call the tech back and have him check it again and see if he thinks it is over charged this time.