Mechanical t-stat with bulb inserted in the coil with CI set at 38/39 and a 14-15 differential will solve the freeze up problems. You are sensing coil temp. A CI of 38 coil should be equal to 38 air temp. The differential is based on a 10 degree TD. A 15 degree differential= a 23 degree coil=33 degree air temp for cut out. Most Freeze up issues are, like you said, doors being proped open or gaskets. That being said, I prefer an A419 with a defrost clock. The electronic stats seem to be more accurate. Plus you can set the ASD to prevent short cycling of the pump.
Officially, Down for the count
YOU HAVE TO GET OFF YOUR ASS TO GET ON YOUR FEET
It was working when I left...
Liberalism-Ideas so good they mandate them