Both red LED lights flash alternately. Outside heat pump was running all the time even with the inside thermostat off. Fount that the relay was stuck and released it. Unit stopped. When I set the thermostat to comeon, everything worked fine, but red LEDS sontinue to flash. Unit is a Rheem that was installed in 2008.

The answer should be on inside of door a list of the codes and what to look for

If the outdoor unit continued to run after the indoor thermostat had signaled a shut-off then you found the culprit. The contactor (relay over 20amps) can get stuck but it is surprising for such a new unit. If plunger is staying depressed even after setting the thermostat to off than it is faulty and should be replaced. The error codes are probably high pressure codes. The unit running by itself without the indoor blower motor would cause the pressure internally to go wayyyy up.

Thinking back I saw this on a Rheem this past summer and it might have been an 07 or 08 heat pump.

I wouldn't worry too much about the codes they will go back to normal when the pressure is gradually disapated. DIY'ing a new contactor is easy and straightforward as long as you get the exact replacement and wire it exactly. I take pics before, that always helps me,or label wires. New contactor $25 give or take.



Good luck