Heater works intermittently

Strictly by accident I determined this is related to the temperature control "arm" was simply not making good contact. All I needed to do was to put some additional rearward pressure on the temp control "arm" and heat was restored. I now have the option of ordering a new control untit ($500) or in true shade tree mechanic fashion I used an ear loop from my blue tooth device to hold it in place ($2) works like a charm.

Nice work! Thanks for the update.