German Truma Combi is an RV Game Changer

While technology and the sciences continue to advance at a rapid pace, the same can’t be said for the technological advancements in the American RV industry. Indeed, with the exception of the slide-out and the Toy Hauler, advancements in the RV industry have been pretty much nil lately. If any breakthroughs have occurred, it’s been due to either European innovations—like the DC compressor refrigerator, Seitz window, and folding bathroom sink—or innovations outside the RV marketplace like the LED light, the lithium ion battery, and solar power.

Fortunately, our friends in Europe have kept the technology train moving by developing revolutionary products for the RV industry. The latest, and most significant advancement comes from Germany, the so-called Truma Combi. What’s great about this amazing little unit is that it functions as both a water heater and a furnace and does so with a 97 percent efficiency. There’s no doubt about it, the Truma Combi is an RV game-changer.

The benefits of the Truma Combi are numerous. First, the dual capable unit takes up half the space in your RV since only one appliance is needed rather than two. Small rigs, like truck campers, can really benefit from the smaller footprint so that the extra space can be utilized for storage or other goodies like an extra batteries. The other savings, of course, is in weight. The smallest offering by Truma—the Combi 4—weighs only 31 pounds. The combined weight of your typical American 30,000 BTU furnace and American 6 gallon water heater is 54 pounds (30 pounds of the furnace and 24 pounds for the water heater with an empty tank). That’s a pretty significant savings in weight, especially for truck campers when every pound matters. Moreover, the versatile Truma Combi Eco Plus can run either on propane (a diesel version is also available) or 110 volts AC power. The amp draw of the unit is quite low, too, with an average 12 volt power consumption of only 1.1 amps for air heating and 0.4 amps during the water heat-up cycle.

Cutaway view of the Truma Combi.

The Truma Combi offers additional benefits to the owner. The Combi 4 utilizes a two-burner flame, making it more efficient by providing two temperature settings (the larger, more capable Combi 6 provides a three burner flame for three temperature settings). Moreover, the unit is nearly silent when it operates—being awakened in the middle of the night by the roar of your furnace is a thing of the past. In addition, the heating elements of the Truma Combi are mounted outside the water tank not inside like the traditional water heater. If you’ve ever had to replace a corroded anode rod in a traditional water heater, you’ll really appreciate this feature. Not only that, but draining the 2.6 gallon water tank for winterizing is easier, too—all you have to do is flip a switch. Finally, the Combi has an easy-to-use control panel that makes operating the unit a breeze.

Truma Combi Control Panel

The Truma Combi is now being sold here in the USA with an office recently opening in Elkhart, Indiana. RV industry giant, Winnebago, has recently gotten onboard and is now offering the versatile, little unit in their Travato traveling van. Likewise Airstream is now installing them in their portable Basecamp models. Unfortunately, due to the $1,500 price tag, truck camper manufacturers have been slow to move. To my knowledge, only one truck camper company—BundutecUSA—currently offers the Truma Combi as an option with industry giant, Lance, reportedly to pull the trigger soon. Yes, the Truma Combi is expensive, but when you consider the amount of space and weight that it saves and how efficiently it operates, it makes a lot of sense to have one in your rig, especially if you do a lot of boondocking and overlanding. It’s time for truck camper manufacturers to get on board on what really is a no-brainer product and stop using antiquated 1960’s technology.

Truma Combi ducting and Pex water connections.
About Mello Mike 899 Articles
Mello Mike is an Arizona native, author, and the founder of Truck Camper Adventure. He's been RV'ing since 2002, is a certified RVIA Level 1 RV Technician, and has restored several Airstream travel trailers. A communications expert and licensed ham radio operator (KK7TCA), he retired from the U.S. Navy in 2004 as a CWO3 after 24 years, holds a BS degree, and now runs Truck Camper Adventure full-time. He also does some RV consulting, repairs, and inspections on the side. He currently rolls in a 4WD Ram 3500 outfitted with a SherpTek truck bed with a Bundutec Roadrunner mounted on top.


  1. Can’t some retro-fitter get a Truma combi comfort plus and install it in my RV? I am willing and prepaired to pay good money for it!!!!

  2. I am trying to buy a TRUMA combi comfort (in Europe and Australia: Truma combi 6 e plus) with propane & electric (110V) operation. I will need it for my Thor Four winds in which the interior stinks from propane and exhaust fumes as we switch the heating on.
    It still does not seem to be available from TRUMA USA nor Canada.
    Any idea how I can purchase one – with the installation included if necessary. I do really need a TRUMA!

    • Truma won’t sell you one for a DIY install. You have to go either through Truma HQ in Elkhart or through an authorized Truma dealer. I recommend giving Truma HQ a call.

  3. Mike,
    There is a fair amount of info and reviews of the Truma Combi propane, but almost nothing on the diesel D6E. Is there any way you could get hold of a D6E for a thorough evaluation? You could have the ONLY rock-solid review on the web.

  4. Last I read they were only available to OEMs. Has this changed? I would be interested in a retrofit potentially.

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