H68.0.02.6C-04
Operating Manual GMK 210
page 11 of 20
_____________________________________________________
_____________________________________________________________________________
9 Rating of Motor Homes and Caravans
Normal humidity should not cause serious problems at faultless and correctly used motor homes
and caravans.
However, the following problems can occur due to increased humidity:
- mildew together with its smell nuisance and health risks
- damage to materials (
wood rots, metals oxidize, “aluminum corrosion”, ...)
The humidity can occur from different sources:
- from the outside: rain water or splash water gets into the structure through leaks in the
vehicle‟s hull
- from the inside: leaky installations and condensation water from humidity disposal of the
passengers, cooking, potted plants, ...
To maintain the value of the vehicle it is important to detect and remove increased humidity as soon
as possible.
The device can detect humidity in structures long before it is visible for human eyes (water
patches). Although the device can even look “into” materials, it does not destroy or damage them.
Exception: metal. If metal structures are very close to the sensor area the device displays too high
values in most cases. Therefore metallic rods, reinforcement, aluminum insulation blankets, metal
wires etc. can cause problems.
9.1 Materials and design
It is important to know the design of your motor vehicle/caravan for well-grounded ratings.
Depending on the actual design there may be different weak points and spots, most likely for water
entry from outside.
Following questions should be answered:
Where are critical points like connection between wall and roof, windows, doors and gates,
shower trays, sealings, gorges)
Are the damages from accidents /repaired areas
Is it a wooden framework construction? Especially common for older models.
Is the hull a sandwich construction? Made of what materials?
Where are metallic rods/reinforcements? Where are metal wires and pipes?
9.2 Defining measuring points for continuous inspection
We recommend to define some measuring points from begin on and check and record them
regularly (at least every ½ year). Humidity risks and impending damages can be recognized very
early then.
Defining the measuring points
The measuring points should be determined deliberately.
Especially weak points (edges/welds, windows, doors, etc.) should be monitored.
An overview of three possible weak points:
roof sealing, window sealing and assembly weld upper to lower trailer body
The reason here: old and porous window sealing
