Hi James

That's great news that you fixed the cold override switch.

But that wouldn't have been the cause of your hot air at other settings, so I suspect that in replacing the switch (which did need to be done) and replacing the HVAC controller head, you sorted out whatever connection problem was caused by the original work you did on the head to replace the bulb!

 

Hot air on the other temp settings would have been a failure of either the inside or outside temp sensors.