I recently installed a new digital thermostat in my Trailmanor. I had the "more common than you think" issue of nothing happening. So I did a quick fix (push and wiggle...see the video) and then ordered a new digital thermostat. Below is some information about how the heater thermostat works and a simple way to troubleshoot it. One thing I failed to mention when trouble shooting the thermostat is to slide the lever all the way to the right (hottest setting), then use the paperclip jumper or the push and wiggle test!
Thermostat failures are more common than you think! Over time the contact inside the thermostat wears, gets dirty or corroded and fails to make contact when the control lever is moved to the right. There is a plastic V shaped tang on the lever that slides under the contact tab, thus lifting it slightly and separating the two contacts. This kills the heater...or turns it off. When the lever is moved to the right the V tab moves out from under the contact tab and allows the connection to be made. When the thermostat is pushed further to the right it eventually reaches the point where heat is called for and another hidden contact engages and provides a signal to the heater to turn on. Yep...there is a lot going on inside that little box.
Over the years I have used 6 different digital thermostats in my campers for Heat-Only systems. If you have a failure, I strongly recommend a replacement with a simple digital "battery operated" thermostat. Battery operated is very important since that implies that it can work without any outside electrical source.
YouTube Video
https://youtu.be/zOnNO5B2NKQ
Suburban Heater Thermostat Failure and Digital Replacement
Linear Mode
