The Truma gets power from Liquid Propane gas, from 110v electrical power, or a combination. The Truma uses 12 volt power for control circuits and blowers only.
The Truma has several heat source modes:
- GAS: propane
- EL1: single 110v heating element
- EL2: two 110v heating elements
- MIX1: gas burner on low, plus one electric element
- MIX2: gas burner on low, plus two electric elements
The Truma will never, ever draw energy from your batteries to energize the electric heating elements.