Truma CP Classic panel (gas) — heating & hot water troubleshooting

Your Truma system heats the van's air and your hot water. This guide is for the CP Classic panel — the one you operate with a turn knob, where faults show as red or yellow blinks you count — on a gas heater.

Good to know before you start

• Your heater runs off the gas bottle in the gas locker — the same gas that feeds your hob.
• Air heating takes up to ~80 minutes to reach full temperature; hot water around 20. Give it time before deciding it's faulty.
• On the panel: green = on, yellow = warming up or a warning, red = fault.
• A quick reset clears many faults: switch the panel fully off, wait 5 seconds, and switch it on again.

Try these first — they fix most cases

1. Turn the temperature up.
   Green light on but no heat almost always means the dial is set below the current room temperature. Turn it toward 5 and wait a few minutes.

2. Close every window — firmly.
   A single window even slightly open (including the small one by the table) trips a safety sensor that shuts the heater off. Walk around and give each one a firm push. (Panel showing yellow ×3? This is it.)

3. Charge the leisure battery.
   No lights at all, or a yellow warning blink, is most often a low battery — this is a very common cause. Plug into shore power at the driver-side socket, or run the engine for about 30 minutes, then switch the heater on again. → Charging your leisure battery

4. Check the gas.
   Yellow ×9 (about 30 seconds after you switch on) means no gas is reaching the heater. Quickest test: try lighting the kitchen hob.

• Hob lights → gas supply is fine, so it's the heater itself. Reset it (off, 5 seconds, on); if it still won't fire, contact us.
• Hob won't light → check the bottle isn't empty (lift it — an empty one feels noticeably light), make sure the cylinder valve is fully open, and press the black safety button on the gas hose.
• Cold weather, but the bottle still has gas? A butane bottle can read as "no gas" once it gets cold, because butane stops vaporising. Use a propane bottle where you can, or warm the bottle up. → Fixing the ×9 gas error

What the fault lights mean

• Green flashing after you switch off — normal. It's a short cool-down run and stops on its own within about 5 minutes.
• Yellow ×1 or ×2 — battery voltage low (or, rarely, too high). Do step 3.
• Yellow ×3 — a window is open or ajar. Do step 2. → Closing the window sensor
• Yellow ×4 — airflow is blocked, or (if you're only running hot water) the boiler is empty. Check nothing is covering the warm-air outlets or the intake grille, and top up the fresh-water tank. → Clearing airway obstructions
• Yellow ×9 — no gas reaching the heater. Do step 4.
• Yellow ×5, ×7, ×8, a steady or 1–8× red light, or green and red together — an internal fault we need to handle. Please don't try to open or repair anything. Contact us (below) and we'll arrange the fix.

Still no heat?

Contact IndieCampers roadside support and we'll get you sorted:

We're quickest on WhatsApp or the phone, so reach us there rather than email while you're on the road.

Want the full manufacturer detail? You'll find the Truma CP Classic operating manual (PDF) in the box below.