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”