Why is my Carthago boiler not producing hot water?

A Carthago camper is standardly equipped with a Truma Combi boiler (a combination of heating and hot water) or, in the higher segments, an Alde hot water system. Some older models have a separate Truma boiler. Each system has its own typical faults, but the basic checks are similar.

Step by step: how to find the cause

Always start with the simplest checks:

• Power supply: Is the boiler switched on? Is the green LED lit? Check the fuse and the residual current device.
• Water pressure: Is there enough water in the boiler? An empty boiler can damage the heating element. Check the water pump and the fill levels.
• Safety valve: Is the pressure relief valve open? If so, water will leak out and the boiler cannot reach temperature.
• Ignition (gas): Do you hear a clicking sound when starting? If not, the ignition electrode or the gas control unit may be faulty.

Specific problems per system

With Truma Combi boilers, the most reported faults are: defective circuit board, worn burner, or a blocked gas line. With Alde systems, the issue is often a broken heating element (230V), a faulty circulation pump, or air in the system. Consult our general explanation about boilers without hot water for more background.

What does a repair cost?

The costs depend heavily on the part. A new heating element typically costs between 100 and 250 euros, a circuit board for a Truma Combi can go up to 400 to 600 euros, and replacing a complete boiler quickly costs more than 1,000 euros. Labour rates at a dealer vary from 60 to 90 euros per hour. Sometimes a repair is no longer economically viable, especially with older campers.