What you can expect in our blog

Starting with general questions about the gas supply, advice about better distribution of the warm air through to advice on how to install products in your vehicle – the blog contains lots of issues related to accessories for your motorcaravan or caravan.

This also includes information about Truma in general or technical reports on day-to-day issues.

Do you have any questions about installing a product or would you like to propose an improvement to one of our products? Then don’t hesitate to leave a comment on the Truma service blog. We would be happy to hear from you.

Heat exchanger

Replacement of the heat exchanger is not necessary for Truma liquid gas heaters

Worried customers frequently ask us about the regulation that stipulates that heat exchangers in vehicle heaters need to be replaced after 10 years.

Here is our detailed explanation: (This can also be submitted to the TÜV/Dekra if they do not have a copy.)
In compliance with the Road Traffic Regulations “Technical requirements for vehicle parts for the type test in compliance with §22a StVZO” dated 05.07.1973 for heaters operated with liquid fuels (diesel, petrol), the heat exchanger must be replaced after 10 years of use.

The reason for this are combustion residues.

In the new version of these “Technical requirements” dated 19.03.1990 the Federal Motor Vehicle and Transport Authority also demands the replacement of the heat exchanger in heaters operated with gaseous fuels after 10 years.

However when liquid gas is combusted, no corrosive elements are created that could corrode the heat exchanger of the liquid gas heaters, so that for reasons of safety, a replacement of the heat exchanger is not necessary.
Knowing this, we are convinced that the safety and quality of the Truma products can always be guaranteed well beyond 10 years, which is why we decided to prevent the enactment of the new version of the “Technical requirements” for the benefit of our customers!

We commissioned a technical report on corrosion to assess the durability of Truma liquid gas heaters from the Research and Material Testing Institute for Civil Engineering, Corrosion Protection department, which came to a very clear result: “Heaters of this type can be operated without problems for 30 years or more, without any signs of leaks caused by corrosion”.

Based on this report we were able to convince the Motor Vehicle and Transport Authority to extend the periods of use of the heat exchangers in liquid gas heaters and the exhaust-carrying pipes from 10 to 30 years in the “Technical requirements for vehicle parts in compliance with §22a StVZO”.

This means that these costly replacements that have no technical relevance and do not benefit the customer are no longer necessary.

This now means that anyone who has installed a Truma liquid gas heater Trumatic C, E or S-K in their motorcaravan is freed of their duty to replace the heater exchangers and exhaust pipes over the next years.


The heater exchangers/combustion chambers in heaters in motor vehicles (lorries and motorcaravan) that were built between 1993 and 2006 must be replaced (after 30 years).
Older heaters have permission to operate in non-compliance and newer vehicle have an E1 code that relieves them of this duty. Example: A replacement duty for e.g. the year of construction 1993 would then come into effect in 2023.
The heat exchangers in caravans are not affected by this regulation.

Diagnosis – frost damage

Maybe the one or other Camper has made the not so nice experience of a leaking waterheater when started up for the first time after the winter.

A reason for this could be that the water was not drained from the waterheater. Or there was still water in the lines that had not been completely emptied because e.g. the caravan was not positioned horizontally.

Always empty the boiler if the vehicle is not in use during periods of frost.

To avoid frost damage to the waterheater, we advise the following:

1. The caravan should be positioned horizontally when draining the water.
2. First disconnect the power supply to the water pump (master switch of transformer)
3. Next, the water is drained from the tank and / or the water pump is removed from the tank.
4. Now open the taps in the kitchen and wet cell, and if your vehicle has pre-mixing valves, set these to warm.
5. Then turn to completely open the drain and venting valve, and pull out.
6. Now check whether the water (5 litres) drains completely.
Our tip:
Use a 5 litre bucket or tank with a filling level scale to check the amount of drained water.
7. You can also blow into the open tap – when set to warm – to blow out any remaining water from the device.

And finally, another bit of advice!
We recommend using agents with active oxygen and silver ions for cleaning, disinfection and care tasks . These disinfect effectively and are gentle on materials and the environment.

Older S-heaters – what you need to be aware of!

Anyone who wants to purchase a vehicle with an older Truma heater should note the following: The device should always be inspected by an expert or qualified workshop to check for faults. After so many years of use, it is possible that there may be gaps in the heat exchanger between the two half-shells that are pressed together with a sealing compound.

If the exhaust fumes (carbon monoxide) leak into the inside of the vehicle, this may, in worst case scenarios, kill the passengers.
Exhaust fumes can also enter the inside of the vehicle from corroded aluminium exhaust ducts. Since 1982 Truma has only fitted exhaust ducts made of stainless steel. Unfortunately, the exhaust ducts cannot be simply replaced 1:1 on heaters built before 1981 because they cannot be connected to the heat exchanger of the old heaters.

More information about “Replacing the heat exchanger”



Winter tips

Wohnwagen in WinterlandschaftFor those campers who do not travel during the winter, it is time to put the caravan into its winter quarters and make it winter proof.

You should remember that both the vehicle and also the installed equipment need to be prepared for the shutdown phase.

Some useful care tips from Truma:

On-board battery

The statistical average battery life is anywhere between 3 and 5 years. However we know of cases where batteries have worked for many more years. Of course, this depends on the type of battery and how it is used. To ensure that the battery does not suffer during the winter, it should be removed from the vehicle before the winter and fully charged.

Five important tips about extending the battery life from Truma

1) For longer periods when the battery is not in use it should be disconnected and recharged every 6 to 8 weeks, at the latest every 12 weeks. Please note that the battery is only fully charged after 24 hours.

2) Adapt the charging voltage to the battery temperature. Depending on type, batteries will heat up more or less during the charging process. The direct ambient temperature also has a significant impact on the performance. If a battery temperature sensor is attached, it will record the operating temperature of the battery and will communicate this to the connected charger. The charger then changes the charging curve based on the sensor measurements. This means, the higher the operating temperature, the lower the output voltage; and the lower the operating temperature, the higher the output voltage

3) Note: The operating temperature range of our charging systems is 0°C to + 50°C. If 50°C is exceeded, the charging process is interrupted.
Using a battery temperature sensor is not only beneficial for the battery, it also increases its service life.

4) For periods longer than 24 hours when the battery is not in use, interrupt the power supply (e.g. with cut-out or disconnection of the battery terminals)

5) The battery should be stored in a cool and dry place protected from frost (e.g. cellar)

Batteries in remote controls or the automatic ignitor of the S-heater
To prevent batteries leaking, they should be removed from the remote control, or automatic ignitor. Store the remote control in a dry place.

Boiler Storage Waterheater
Drain the waterheater via the drain valve.
There are detailed instructions on how to drain the waterheater correctly in this article “Diagnosis – frost damage”.“Diagnose Frostschaden”

Controller System
Always disconnect the pressure controller (or high-pressure hoses) from the gas cylinder to ensure that there is no more gas in the lines.
If there is a gas remote switch, set it to OFF.

1) If the Mover is heavily soiled, spray clean with a soft water jet to remove any mud etc.

2) Ensure that there are no stones or branches caught on the Mover.

3) After cleaning, dry and then apply a light coat of spray oil or a similar water-repellent lubricant onto the guide elements of the drive.

Attention: The lubricant may not be allowed to get onto the rollers or tyres!

Engage and disengage the drive units several times to ensure that the lubricant is distributed across all guide elements. Do not park the caravan with engaged drive rollers.
If cared for correctly, both the vehicle and the Truma products will survive the winter without any problems. And you can start travelling again in the springtime without any worries.

Caution: left-hand thread

Things new campers should know about the gas supply in caravans and motorcaravans

Connection screws to gas cylinders with flammable content always have left-hand threads. This different turning direction ensures that no mistakes can be made.
The left-hand thread screw connections, e.g. hex nuts, are always marked with a notch (see figure links). This is standardised and anchored in the DIN EN 15202 as follows for liquid gas cylinders: “The corners of the hex nuts with left-hand threads must bear a notch for better recognition (e.g. a 60°-V notch).“

This picture shows one of the more rare left-hand thread wing nuts with notches.

In contrast, left-hand thread wing nuts do not always bear a notch, because this is not stipulated in the standard.


Well equipped for the first tour

How should I prepare the caravan for the travel season?

The following contains useful tips for restarting the heater, boiler etc. after the long winter break.

1. S-heater: (cleaning)

To do this, remove the cover from the heater.
Remove all dust deposits on the heat exchanger and base plate.

Use a small paint brush or brush to carefully remove any dust on the fan wheel of the Trumavent fan.
Also, check the exhaust cowl for damage and soiling (e.g. leafs).

1a. Battery in the automatic ignitor of the S-heater:

Insert battery – if you cannot hear a sparking sound, or only at intervals of more than one second, the battery needs to be replaced (only when the heater is switched off)
Only use temperature-proof (+70°C) leak-proof Mignon batteries, other batteries may cause malfunctions.

2. Storage Waterheater

Check the waterheater for leaks.
If there are any leaks, the inner tank can be replaced, either by our mobile service or an authorised Truma service partner.

Anyone who wants to tackle the replacement themselves, can do so by following instructions.

3. Controller system:

Connect the pressure controller, or high-pressure hoses to the gas cylinder.
Set the optionally installed gas remote switch to ON.

4. Mover:

Place the batteries into the remote control.

5. On-board battery:

Charge the battery. Please note that the battery is only fully charged after 24 hours.
During charging, please remember to adapt the charging voltage to the battery temperature.

Depending on the type, batteries will warm up more or less. Also, the direct ambient temperature of the battery has a significant influence on the performance.

If a battery temperature sensor is attached, it will record the operating temperature of the battery and will communicate this to the connected charger. The charger then changes the charging curve based on the sensor measurements.

This means, the higher the operating temperature, the lower the output voltage; and the lower the operating temperature, the higher the output voltage.

Note: The operating temperature range of our charging systems is 0°C to + 50°C.

If 50°C is exceeded, the charging process is interrupted.

Using a battery temperature sensor is not only beneficial for the battery, it also increases its service life.
Truma wishes you a pleasant summer season!


Installation of Truma Mover® – also in your vehicle

It is possible to fit the Truma Mover® into almost any vehicle. Depending on the specification there are accessories available to ensure that it can be fitted to all standards fames.

On a standard frame with an L-profile or U-profile, no further accessories are required if it is mounted in front of the axle. The universal attachment set contained in the delivery scope fits this frame.

If the unitDistanzsatz_30mm_60030_95000 is attached behind the axles, the distance between the centre of the rollers and the tyres may be too large for assembly. The distance kit is used here to compensate the frame height.

If your vehicle has a standard flat frame, a BPW flat frame Vario III one-piece or a BPW flat frame Vario III two-piece, the unit can be fitted easily before or behind the axle. This is made possible thanks to the flat frame kit that is required to compensate the low frame height.

If you have an ALKO Vario III Chassis, the unit need to be fitted behind the axle. To reinforce the lightweight frame, you will need the Assembly Kit ALKO Vario III/AV as an accessory.

The Mover® is attached in front of the axle on the Eriba Touring because, if mounted behind the axle, the waste water pipe system needs to be moved. The Eriba Touring installation kit is required to supplement the rectangular profile.

Selecting the right air conditioning system

The Truma air conditioning systems are imperative to ensure you can enjoy a pleasant and relaxed trip. But what do you need to take into account when choosing a system?

When choosing the rightAventa_Comfort_44090-01_Spiegelung_5cm air conditioning system for your recreational vehicle, you need to take into account your personal preferences and the specifications of the vehicle into account. If you have a long vehicle, it is worthwhile using two Truma air conditioning systems and opting for the comfort models of the Truma air conditioning systems; two of these systems have the benefit of an added heating function (Aventa comfort and Saphir comfort RC). This may be useful between the seasons. You also need to decide whether to opt for a rooftop model or a under-bench model. Rooftop air conditioning systems are installed in a flat, space-saving and aesthetic manner onto the roof from where the air is distributed inside the vehicle. In an under-bench system air is distributed flexibly by fitting coldSaphir_comfortRC_44033_01_Spiegelung_72 pipes. The centre of gravity of is placed on the floor of the recreational vehicle. Think about the fuses in place at the camping sites you visit. Do you travel to areas with low fuses, or is economic use of power important to you? In this case, you could opt for the eco or compact models. All Truma air conditioning systems are compressor systems that both cool and dehumidify the air to create a pleasant room climate.
You should also consider your personal cooling and travel preferences. If you like travelling to the Mediterranean where the air humidity is higher, your cooling requirements will also be higher. If you cook or shower frequently in the vehicle, this will also raise the air humidity. A family vehicle with several passengers heats up more quickly. If you want to cool the entire vehicle, you will need more energy than if you only cool the bedrooms.