Heat Pump Occasionally Emits Cold Air

I have a 9 year old heat pump on my roof (a Trane) that is being temperamental and I would appreciate an experts guidance. In the past few months there have been times when it is emitting cool air when the heat is on and/or it emits hot air when the A/C is on. Sometimes the temp is OK, but it feels like there is very little air at all coming out of any of the vents. A couple of months ago I had an HVAC tech out for an annual check up and described the problem to him. He cleaned the filter and said that the freon was fine. He also suggested that the outdoor fan bearing is worn and a contactor is worn. His recommendation was that, if it got worse, I should replace the motor and contactor. When I try and research the "symptoms" myself via the web, I get very different information. I don't want to be taken advantage of or replace the wrong part and would appreciate some guidance and/or recommendations from other experts in the field. Thank you so much.

It does sound like a stuck reversing valve, but that is not usually intermittent. It could be a loose wire/bad connection somethere in the B/O thermostat wire circuit.

What is Your Model Number ?

It does sound like the HVAC tech blew some smoke.

Jimbo's answer sounds a lot closer to me.


Could also be something as easy as replacing the Thermostat batteries if it is Electronic.

A heat pump WILL do that when it goes into "defrost/antifreezing" mode to send hot gases through the system to melt an icing condition.

And furnaces have off delays, some blow a lot of cool air to extract heat from the coil or plenum.