1. A 212 code usually means that there is no LP getting to the Truma.
Both the inside and outside LP switches need to be turned ON in order to use LP inside the van.
In addition, the LP solenoid switch on the top of the Truma itself needs to be turned ON in order to use the Truma on the LP/GAS mode.
If you have an LP stove and if you have LP at the stove and it will run for a long time but the Truma will not work on LP then it’s POSSIBLE that you have an issue with the regulator, usually cured by replacement of the regulator. Note that the stove is much less particular about the gas pressure available so just the fact that the stove works doesn’t mean that the regulator doesn’t need replacing.
Sometimes the 212 code can be cleared by re-setting the Truma itself by using the re-setting the Truma instructions elsewhere in these FAQ’s.
2. A few people have learned that the 212 error can be triggered by issues with the intake or exhaust air connections/lines to or from the Truma, most frequently due to one of the clamps holding the tubes to the Truma having become loose and sometimes due to a kink/blockage in the tube.