Webasto Air Top 3500 ST Installation Instructions Manual page 10

Installation Air Top 3500 ST / Air Top 5000 ST
A seal (Figure 4) must be fitted between the heater and the vehicle body.
This seal must be replaced each time the heater is installed. The
support area for the heater foot must be flat. A special tools can be
purchased from Webasto to drill the holes and, if necessary, smooth the
support area. The seal can compensate for unevenness of max. 1 mm.
Ensure that all moving parts can move easily.
Fig. 5: Installation
IMPORTANT
After installation, check that the casing is not in contact with any parts of
the vehicle body. A failure to do this may result in the hot air fan blocking.
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