Mach Thermostat Problem

We were camping last weekend and it was our fourth camping trip since buying our Sundance XLT. The heater functioned perfectly on all occasions including the first night on this trip. After waking up with the heater running constantly (burning up) I was only able to shut it off with the cool-off-heat switch, adjusting the temp had no effect. I pulled the fuse and reinstalled to see if it simply needed to be reset but that did not fix the problem so I thought the t-stat had failed. I don't know why but I noticed the A/C fan switch was on HIGH and we usually have it on low. So, I switched the fan to low and tested the heater and the t-stat functioned normally. At this point I think it is an incompatibility between the MACH t-stat and the Airxcel Suburban Gas Furnace. Maybe the factory has had some issues with this reported from other owners.

Sounds very similar to an issue we had this past season with our Mach 3. I didn't notice any kind of connection problem. Maybe an internal connection at the T-stat? We replaced the thermostat and that solved the problem for us. I should mention that this was an issue with our air conditioning side of things. We got our thermostat here:
Coleman-Mach Thermostats