Thanks for the replies.
I ended up calibrating the thermostat.
When I got there it was turning on when I rotated the dial to the 65 deg mark and shutting off when the dial was rotated t the 60 deg mark. The actual temperature was reading 75 deg. I adjusted the calibration using the allen head adjustment pot. It now kicks on at 75 deg. and shuts off at 65 deg.
As I increased the upper set point the span increased as well. There didn’t seem to be any way to decrease the span separately but I think it’s going to work fine. The real test will be next winter when it gets cold again.
I’ll just have to wait and see if he’s happy with it.
