Truma Varioheat middle of the night ignition failure lockout

[DanielBoondock]

Couple times on our March trip back from the factory the cabin heater got stuck. No heat, loud fan blowing. Consulting with Gemini I found the following, that its probably a lockout state caused by an ignition failure. The heater is running the fan full blast to clear out the ignition chamber of unburned propane. Can be caused by a low 12V line (not the case here with the max battery pack), or a propane line drop. Low nighttime temps cause the propane to contract and lower the pressure, explaining why it only happens then. Another possibility is moisture in the tank. Being new to the trailer and it being middle of the night I didn’t catch an error code, but most likely due to this. 

Possible fixes to prevent are to …

• Go to a place that can put a little methanol in the tank prior to filling to act as an antifreeze (a bother)
• Wrap the tanks (30lb on mine) in a heating blanket (expensive at $500+ each)

The propane lines are set to 11” pressure by RV regs, so increasing that isn’t an option. 

Being out West we frequently travel between temperature extremes so I’d like to be generally prepared to prevent this from happening again. I’m wondering if there’s a low cost way tank heater blanket solution? Or other ideas, we have 30 lb tanks.