E 212 HCombustion air, gas, overheat, or electronics fault
E212H has several possible causes. The code alone does not identify a failed part; start with model confirmation and the external checks below.
Plain-English answer
E 212 H has several manufacturer-listed causes: a blocked combustion-air inlet or exhaust, a closed gas valve, defective gas-pressure regulation, activated overheat protection, or faulty electronics.
What to check first
- 01
With the appliance off, look at the outside combustion-air inlet and exhaust for an obstruction. Do not insert tools or dismantle the terminal.
- 02
If there is no gas odor, check the accessible appliance gas shutoff using its normal control. Do not adjust regulators or loosen fittings.
- 03
Turn the Combi off, let it cool fully, fill the water container with cold water, and clear interior air openings.
Stop and call a technician when
- For gas odor, a carbon-monoxide alarm, soot, or damaged exhaust, leave the RV and obtain emergency or qualified assistance from a safe location. Do not restart the appliance.
- If E212H remains or returns after the permitted checks, stop repeated resets and contact Truma or a qualified technician. Do not replace a regulator or control board from this code alone.
Check the exact manual
Applicability: Truma Combi — US reference; exact model confirmation required. The data plate and specification letter determine which procedure is correct.
Open Truma Combi error-code tech tip ↗Source reviewed September 21, 2026Reference: Truma US, Tech Tip: Truma Combi Error Codes, published October 1, 2025, entry “E 212 H”. This is a web article, not a model-specific manual or a confirmed diagnosis. Use the Truma Download Center to match your appliance manual; select the appropriate regional site for other markets.
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