Last Updated: May 10, 2021
Truma Combi D 6 Altitude Kit
When you spend a lot of time in the mountains with your camper or RV you are going to want to consider an Altitude kit for your Truma.
We installed one on our Truma Combi D 6 from the outset, and it has been super handy in the Alps of Switzerland where you are often above 1500 meters (5000ft).
Truma Combi Altitude Kit Switch
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What Does The Truma Combi Altitude Kit Do?
The Truma Combi Altitude kits is a switch you install that runs the heater better at altitude. It is designed to run between 1500 – 2750m (5000-9000ft).
And if you travel anywhere with mountains, these heights are easy to reach! And if you park and camp at these heights your Truma will operate either far less efficiently or not at all.
Why Is Altitude a Problem for Heaters?
If you know anything about engines then you know that they use a mixture of fuel and air to run.
Problems arise when you go to higher altitudes because the air gets thinner – which is to say you get less oxygen.
If you have less oxygen then the fuel the heater is using might be too rich (too much) and not burn well, or not burn at all. The mix of fuel to oxygen needs to be optimized.
Most modern cars cope with this automatically, and to some extent, the Truma heaters do too. However, when you get really high you can start to have trouble running your heater!
Installing the Truma Combi Altitude Kit
The altitude kit is a simple addition to your Truma Combi that comes with a small device and a switch.
The switch should be mounted to a spot where you can easily access it so that you can change it when you camp at higher altitudes.
Our altitude switch is mounted on the back of the box where our heater is and can be easily switched from the rear of the vehicle.
Truma Combi Error Code E121H
This article is not about Truma Error Codes, however, I thought this was worth pointing out because I could not find anything on the internet about it
Truma Error Code E121H is an error that occurs when the Altitude Kit is switched to the wrong setting.
We experienced it last week while camping below 1500m / 5000ft but had accidentally moved it to the higher altitude setting.
Note: I am not sure if the reverse was true (camped at high altitude in the low altitude setting) if it would show the same error (maybe you can tell me in the comments)
The heater functioned normally from the control panel, until it got started and a lot of air was blowing cold through the van.
It then threw that error code on the Control Panel and was hard to switch off.
Another interesting thing I noticed was that I had trouble turning the fans/heater off – which was annoying as it was blowing cold air into our cold van!
I had to hit the back button, switch off all heating settings (heater – off, boiler – off) and then cut the power.
If you don’t turn the heaters off, and cut the power to kill the heater, it will probably come back on.
About the Author Roger Timbrook
Roger is a little obsessed with travel. He has been to over 40 countries, broken 3 suitcases and owned over 10 backpacks in 12 months. What he doesn't know about travel, ain't worth knowing!
