No 12 V power supply or battery voltage too low (< 10.5 V).

Check battery voltage, check boiler fuse (1.6 A slow-acting) on electronic control unit.

Cowl cover is fitted, no gas supply, incorrect gas pressure, or air in gas supply.

Remove cowl cover, check gas valves and cylinder, and switch appliance off, wait for 5 minutes, and switch on again to bleed air.

Overtemperature sensor has activated.

Check the water content, top up if necessary by closing the drain valve, switch the appliance off, wait for 5 minutes, and switch on again.

Water pressure too high (> 2.8 bar).

Check water pressure and use a pressure reducer if connected to a central water supply.

Hot water flowing back into cold water supply.

Fit a non-return valve to the cold water supply.

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Truma • Water Heaters

Truma Gas Boiler (BGF)

Q: No 12 V power supply or battery voltage too low (< 10.5 V).

Check battery voltage, check boiler fuse (1.6 A slow-acting) on electronic control unit.

Q: Cowl cover is fitted, no gas supply, incorrect gas pressure, or air in gas supply.

Remove cowl cover, check gas valves and cylinder, and switch appliance off, wait for 5 minutes, and switch on again to bleed air.

Q: Overtemperature sensor has activated.

Check the water content, top up if necessary by closing the drain valve, switch the appliance off, wait for 5 minutes, and switch on again.

The Truma Boiler Gas BGF is a liquid gas-powered water heater designed exclusively for installation and operation in caravans, motor homes, and mobile homes. It heats drinking water up to approximately 70 °C and can be operated simultaneously with gas and electricity for faster heating.

Technical Specifications

Gas Pressure Mbar30 mbar

Power Consumption 12vIgnition: 0.25 A, Heating: 0.21 A, Standby: 0.06 A

Water Capacity Litres10 litres

Weight Kg7.5 kg

Master Troubleshooting & Diagnostics Matrix

Error Code / Indicator	Symptom / Meaning	Step-by-Step DIY Fix	Suggested Actions
`Operational Fault`	No 12 V power supply or battery voltage too low (< 10.5 V).	Check battery voltage, check boiler fuse (1.6 A slow-acting) on electronic control unit.	DIY Safe
`Operational Fault`	Cowl cover is fitted, no gas supply, incorrect gas pressure, or air in gas supply.	Remove cowl cover, check gas valves and cylinder, and switch appliance off, wait for 5 minutes, and switch on again to bleed air.	DIY Safe
`Operational Fault`	Overtemperature sensor has activated.	Check the water content, top up if necessary by closing the drain valve, switch the appliance off, wait for 5 minutes, and switch on again.	DIY Safe
`Operational Fault`	Water pressure too high (> 2.8 bar).	Check water pressure and use a pressure reducer if connected to a central water supply.	DIY Safe
`Operational Fault`	Hot water flowing back into cold water supply.	Fit a non-return valve to the cold water supply.	DIY Safe

Frequently Asked Questions

Q: What should I do if I smell gas?

Avoid ignition sources, extinguish naked flames, do not operate electrical switches, mobile phones, radios, or start the vehicle engine. Open windows and doors, evacuate all persons from the vehicle, shut off gas cylinders or gas supply from the outside, and have the gas system inspected by experts.

Q: Can I operate the boiler while driving?

Yes, provided a safety shut-off device like the Truma MonoControl CS is installed according to UN ECE regulation 122. Otherwise, the gas cylinder must be closed during transit.

Q: How do I clear a fault indicated by the red LED?

Switch the appliance off at the control panel, wait for 5 minutes, and switch it on again.