Combo Water Boiler/Furnace Heater Now Here in N. America


[Back] Roads Scholar
Found this post on my Class B Forum....this interesting, space saving product may be of interest to some of you DYI’ers?

Truma Combi 4 Propane Combination Water Boiler and Furnace Heater Now Available in US and Canada

“Now available to the North American market to the aftermarket!
Previously these units were only available to OEM's but we have a access to complete Truma Combi Kits (at a significantly lower price than importing from the EU, and these units are actually approved for us in US and Canadian RV's.”

More information available here:

These are Gas (Propane) and they have limited availability of Dual Propane + 120VAC units as well.

Re-Posted from the Class B (camper vans) Forum
Discount code for ClassBForum Members $50 OFF "classb"


[Back] Roads Scholar
From company’s website:
More details about Truma Combi 4

Enjoy twice the comfort with Truma Combi 4: space and water heater in one appliance. This saves space and weight in your motor home or caravan. A 10-litre water tank, which is also heated in winter, is integrated into the system. In summer mode you can heat the water independently of the space heater. The warm air flows into the vehicle’s interior through four air outlets where it is distributed optimally to ensure a pleasant indoor climate. The Truma Combi heater is almost silent and extremely economical to run.
Your Truma Combi 4 is controlled conveniently with a digital control panel. If you also have a Truma air conditioner in your vehicle, you can select the automatic climate control option on the control panel. It automatically coordinates the Combi heater and air conditioner and keeps your preferred temperature constant in all weathers.
  • FrostControl, the drain valve that works without electricity, fitted as standard
  • Digital control panel CP plus iNet ready
  • Automatic climate control in combination with a Truma air conditioner
Dimensions (L x W x H) 510 x 450 x 300 mm

(Sorry, you’ll have to convert those numbers yourself)


Engineer In Residence
~$2,200 may seem a bit pricey. But try building a system for making hot water and air that is anywhere near the compact. You would likely need 2-3x the space for a american style RV water heater and furnace. Both would require large cut-outs in the side of the vehicle. While the Truma unit can vent through the floor or wall with a much smaller footprint. Plus the variable output means much less cycling for heating the cabin.

Cost wise you would still spend $1k in materials minimum, plus your time/labor to install.


The EPA doesn't have anything to do with it as far as I know. It's purely there own choice.
Yeah the EPA would charge thousands just to certify a diesel unit IF it met their standards on the first try. It wouldn't, as-is, so add the cost of redesigning the unit then testing and multiply it by however many times those standards change. It's their choice because they know better. That's why we get new diesel engines in light trucks every time EPA standards change: the engines are designed to those standards and it's cheaper to design a new engine each time than redesign an old one to new standards.

Propane is largely considered a heating/cooking fuel, not a motor fuel, but I'll just betcha the days of unregulated exhaust from RV water heaters and furnaces are numbered.


Well-known member
Propane is largely considered a heating/cooking fuel, not a motor fuel, but I'll just betcha the days of unregulated exhaust from RV water heaters and furnaces are numbered.
I don't doubt it.

[Placeholder for propane fueled RV devices]