E112H / E212H

Truma Furnace: “E112H / E212H”

danger RV furnace fault codes

Safety This is a propane/LP-gas combustion fault. If you smell gas: do NOT operate switches, ignition or flames — close the cylinder valve, ventilate, and leave the area before doing anything else. Do not clear repeated ignition lockouts without finding the cause; repeated failed ignitions can release unburned gas. Internal regulator/electrode/exhaust work should be done by a qualified RV gas technician.

What it means

Gas/flame fault group: the burner did not ignite or the flame was not detected, and/or combustion air supply or exhaust is restricted. E112-type points to no/lost flame (closed gas, poor earth, regulator/ignition); E212-type adds blocked combustion-air intake or exhaust or a defective gas-pressure regulation system. The unit locks out on gas operation.

Most likely causes

Gas cylinder valve closed or the gas shut-off valve switch on the unit is off / out of gas most likely
Gas-pressure regulator failing (other appliances may still work because the boiler needs more gas) common
Poor or missing earth/ground on the power supply or Combi minus connection (interferes with flame detection) common
Combustion-air intake or exhaust cowl blocked by ice, slush, leaves or debris common
Dirty/worn ignition electrode, flame sensor, or faulty solenoid valve less common

Safe checks you can do yourself

Confirm the propane cylinder valve is open and there is gas; verify the unit's gas shut-off switch is on
Check that other gas appliances light normally (helps point at the regulator)
Inspect the exterior combustion-air/exhaust cowl and clear any ice, leaves, or debris
Visually check that the heater's ground/earth wiring is secure
Switch off, wait, and attempt a clean restart on gas

How to reset / clear E112H / E212H

Correct the cause (open gas, clear intake/exhaust, fix earth), then switch the unit off and back on at the panel to attempt re-ignition
On CP plus, press and hold / double-click the displayed code until the menu appears, then back out to clear it
If the lockout persists, some units have a reset button on the control PCB under a side cover of the boiler — only access this if you are competent; otherwise have it done by a technician

When to call a technician

If gas is confirmed open, the intake/exhaust clear, and earth is good but it still will not ignite or the code returns, stop and have a Truma-qualified technician check the regulator, ignition electrode, flame sensor and PCB.

Applies to

Combi 4 · Combi 6 · Combi 4 E · Combi 6 E · Combi Eco Plus · Combi Comfort Plus

FAQ

What does Truma Furnace code "E112H / E212H" mean?

How do I reset Truma Furnace E112H / E212H?

Correct the cause (open gas, clear intake/exhaust, fix earth), then switch the unit off and back on at the panel to attempt re-ignition On CP plus, press and hold / double-click the displayed code until the menu appears, then back out to clear it If the lockout persists, some units have a reset button on the control PCB under a side cover of the boiler — only access this if you are competent; otherwise have it done by a technician

What is the most common cause of E112H / E212H on a Truma Furnace?

The most likely cause is gas cylinder valve closed or the gas shut-off valve switch on the unit is off / out of gas.

Related · Truma furnace

E2H / E16H
VarioHeat ignition/flame fault: the furnace released gas and… E43H
Over-voltage: the supply voltage to the heater is too high (… E44H
Under-voltage: the supply voltage to the heater is too low (… W18H
Warm-air outlet or circulated-air (return air) intake is blo… W25H–W29H
VarioHeat voltage and airflow warnings: W25H = overvoltage a…

Sources

Tech Tip: Truma Combi Error Codes — Error codes E112H, E202H, E211H, E212H (gas/overheat group) (Truma (official US site))
Truma CP plus Error Codes (Combi) — Codes 112/116/117/202/212: flame not detected, bad earth, gas closed, combustion air/exhaust blocked (Ember RV (OEM-hosted Truma table))

Note: Truma's documented codes for the gas/flame group are E112H, E202H, E211H, E212H (and underlying fault numbers 112/116/117/202/212). The exact label 'W543'/'543' appears on some control panels/integrators for a flame-detection fault but I could not confirm '543' in a primary Truma table during this research, so the specific 543 mapping is treated as lower-confidence; the underlying meaning (flame/ignition failure) is well supported.

● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.