Truma CombiNeo 4 (E) / CombiNeo 6 (E)
The Truma CombiNeo is a combined warm air heater with an integrated water container (5.6 litre capacity) designed for installation in motorhomes and caravans. It supports gas, electrical, and mixed operational modes to provide efficient room heating and rapid hot water generation, even during vehicle transit.
Technical Specifications
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|
Appliance will not start | Gas supply disrupted or air in the gas line. | Ensure the gas cylinder and shut-off valves are open. Several starts may be required to fill the gas line with gas up to the appliance. | DIY Safe |
W434H | No more air bubbles in the water container. | Switch off pressure pump, open FrostControl manually for about 15 seconds to drain approx. 2 litres of water, close FrostControl, switch pump back on, open hot water tap to bleed air, and wait briefly for the air bubble to rebuild. | DIY Safe |
Operational Fault | FrostControl is open. | Close FrostControl. | DIY Safe |
Operational Fault | Bottom outlet of FrostControl or L-piece blocked, water pipe frozen, or aeration system blocked. | Check openings for dirt, slush, ice, or leaves and remove; thaw frozen water pipes; check venting hose for kinks or blockages. | DIY Safe |
Operational Fault | Elbow connection valve calcified or dirty. | Descale, clean, or replace the elbow connection valve. | DIY Safe |
Operational Fault | Water pressure too high. | Check pump pressure (max. 2.8 bar / 280 kPa). When connected to central water supply, use a pressure reducer. | DIY Safe |
Frequently Asked Questions
Q: Can the CombiNeo be operated while driving?
Yes, operation while driving is permitted provided that national regulations and rules are followed, and an appropriate safety shut-off device (such as Truma MonoControl CS or DuoControl CS) is installed.
Q: Why does FrostControl open automatically?
FrostControl opens automatically at temperatures below approximately 3 °C to protect the water system from frost damage, or in the event of overpressure in the system.
Q: How do I deal with winter operation using gas?
For operation at temperatures below 10 °C, propane must be used because butane stops vaporizing at around 0 °C.
Q: How often must the water container be descaled?
The water container must be descaled once a year or whenever prompted by the control panel.