Gas and Oil Home Heating Furnaces - Heat Pump problems

We have a York Heat Pump and York Forced Air Electric furnace. This morning (Christmas eve of course) the house was so cold (16 degrees Celcius) and air conditoned air was blowing out of the vents. I called the service tech. and he finally told me that the valve in the heat pump was stuck in the air conditioned position. He went on to let me know that it was a 5 hour job and the cost (parts and labour) would be $700-$800 (Canadian). This long winded explanation is just to ask: 1) Is his explanation possible (he didn't even take the cover off the pump). 2) If so, is this a "home repair" situation.
Thanks for your indulgence.
From:
Even colder in Canada than normal.:)

the problem.BUT, I am not there.He probably turned power on and off outside or cycled tstat---doing one or the other should have shifted the RV..When it does it has a definite sound.If your unit is not in warranty check on price of replacing entire OD unit---since all components are the same age.Hopefully you have shifted to emer. backup heat.PDF:(

Tks for the reply PDF member. Appreciate your comments.
Kevin

You may very well have a changeover valve problem , but you also could have a bad soleniod for a 20 dollar bill (US).. Was a short circuit in the low voltage wiring check out? COV valves don't usually go bad unless you've had a bad compressor/burnout changeout done and the system wasn't cleaned up. COV's are pretty reliable. I'd recommend getting a second opinion. Yes, I too hope your emergency heat is working.

Tks. for your help. A second opinion is allready in the works. Looks like I will probably just change the whole unit, IF, it is the valve. No use having a new part and a 20 year old unit. And yes, I do have the emerg. heat operating and I find it much warmer without the heat pump working, even when it was working well.