This is usually a quick fix — let's work through it together. Your camper heats both its air and your hot water from one Truma unit, running on either a gas bottle or the van's own diesel tank. Most "it's not working" cases come down to one of four things, so try these first — they fix the majority, whatever van you're in.
First, two quick expectations
- Heating is slow to build — give it up to ~80 minutes to reach full temperature (hot water around 20). It may be working fine and just warming up.
- On the panel: green = on · yellow = warming up or a warning · red = fault.
Try these four first
- Turn the temperature up. Green light on but no heat almost always means the dial (or set temperature) is below the current room temperature. Turn it up and wait a few minutes.
- Close every window — firmly. A window even slightly open (including the small one by the table) trips a safety sensor that stops the heater. Walk round and give each one a push.
- Charge the leisure battery. No lights at all, or a yellow warning, is most often a low battery. Plug into shore power, or run the engine ~30 minutes, then retest. → Charging your leisure battery
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Check your fuel.
- Gas van (bottle in a locker; the hob runs on gas) — make sure the bottle isn't empty and the cylinder valve is open. Quick test: does the kitchen hob light? If yes, gas is reaching the van.
- Diesel van (runs off the vehicle's fuel tank) — make sure you have diesel and you're parked reasonably level. The heater stops itself before the tank runs dry, so it can cut out with fuel still showing.
Still not working? Find your exact fault
First, which panel do you have?
- A knob you turn, with faults shown as blinks you count → CP Classic
- A screen with numbers → CP Plus
CP Classic — open the guide for your fuel; it reads your blink code and walks you through the fix:
CP Plus — your screen shows a code. Jump straight to it:
No hot water, or water draining under the van?
In cold weather that's usually the FrostControl anti-frost valve doing its job — it drains the boiler when it gets close to freezing (below about 5 °C) so the water can't freeze inside. It's normal, and easy to reset once things warm up. → How the FrostControl system works
Still stuck?
- 💬 WhatsApp — message us here
- 📞 Call us — available in your rental agreement