The Truma Combi D comfort allows you enjoy twice the comfort with a diesel-powered furnace and water heater in one compact appliance.
Technical Details
Reduce your dependency on propane with Truma Combi D comfort. Truma’s revolutionary two-in-one furnace and water heater is available as a diesel-powered solution for motorhomes with diesel fuel. Take refuge in a cozy camper in the winter months and wash off with a hot shower all year round. Combi D comfort shares the same footprint as other Combi options to save space and weight in your RV. The Combi D comfort features six operating levels to achieve the desired temperature more efficiently.
Truma introduced the Combi to the RV industry in 2007, the first RV furnace of its type. Since then, Truma has continued to innovate and evolve this heating technology. Hot air and hot water from one smart appliance provide the comforts of home while out on the road. The water tank is integrated into the furnace, providing hot water while it produces hot air. When the weather is warm, you can use your hot water without running the furnace.

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Truma Combi owners are just one step away from achieving complete comfort. You can already manage your heat and hot water with one appliance, controlled by the CP plus control panel. Now you can upgrade your RV with a brand new Truma Aventa rooftop air conditioner with its own dedicated wireless remote control.
The Combi D furnace requires ultra-low-sulfur diesel (ULSD) fuel with max. 15 ppm sulfur according to ASTM D975 and SOR/2005-305.
We recommend keeping the gas tank at least 1/4 tank full to support uninterrupted fuel delivery.
Error Codes on the CP plus:
If the system has been sitting for an extended period of time:
If you are above 12,000 feet and are trying to cold start the Combi D:
If the system has recently been running:
If the problem continues, please contact us for assistance.
If your Truma Combi will not stay lit but you are not receiving an error code, check to make sure the tank has not frozen. If the tank freezes, it can become swollen and restrict the air flow into the ducting. This could cause the unit to overheat and cycle off. If the error persists, please contact Truma Customer Care for additional support.
If a generator is installed, start the generator before starting the Combi D. This will ensure the Combi D does not draw air from the generator fuel line.
It is recommended to reduce the risk of condensate dripping down the exterior wall of the RV, which can cause damage to the side wall over time. The spout can also be used for the Combi propane variants, but because propane tends to have lower particulate matter emissions it is not required.
Yes, it can remain attached while driving. Since it just clips into place, it can be removed then reattached once parked and prior to using the Combi.
We recommend it be replaced to help protect the sidewall of the RV. Replacements will be available on our Amazon store.
Please refer to your RV manufacturer’s instructions for winterizing and bypass valves.