Having a problem with my heat pump system. The thermostat is set to cool but the unit is blowing hot air. If it has been turned off for awhile and we turn it back on to cool (fan set to auto), it will blow at what seems to be room temperature for awhile (5-20 minutes) and then turns to hot air again.

Anybody have any ideas on what may be wrong?

If your outside condensing unit is running and you get a little cold air, you're probably low on refrigerant. Check the outside unit to see if the condenser fan is turning and try to listen for the compressor. You also could be having problems with the reversing valve.

Condenser fan is not turning. When I touch R to Y I get a click outside but that's all.

Check all breakers going to the a/c, inside the house main panel and outside at the unit. It will be a two pole breaker around a 40 amp. Turn it off and then back on to get it to reset.

Reset all the breakers inside and the large t-handle one outside. Had my wife turn unit to "cool" inside and it clicked, paused and then condenser fan started running and almost immediately stopped.

BTW the outside unit is a Bryant 661CT048-C; inside unit is a Carrier; thermosat is a Honeywell manal digital unit (8011?)

Reset all the breakers inside and the large t-handle one outside. Had my wife turn unit to "cool" inside and it clicked, paused and then condensor fan started running and almost immediately stopped.

BTW the outside unit is a Bryant 661CT048-C; inside unit is a Carrier; thermosat is a Honeywell manal digital unit (8011?)
Sounds like it tripped the breaker again. Compressor may be stuck, bad run capacitor or just a shorted wire. Its time to call a service tech, if you know nothing about electricity a unit going to ground can hurt you bad. Sorry I know that's not what you wanted to hear.

Thanks T-Top. Thougt it might come to that but wanted to see if it was something simple like the thermostat first.

I appreciate the help... I'll be calling a tech.