Webasto Thermo Top Z Notice De Montage page 42

Thermo Top Z / Thermo Top C
Connection to the vehicle cooling system
7.1. To retrofit the circulating pump (retrofitting only)
Make the electrical connection as shown on the circuit diagram. The
circulating pump may be installed either on the space available for it on
the heater or in the water system away from the heater.
Ensure that that water passes through the heater correctly (water outlet
at the top / water inlet at the bottom) (otherwise it will malfunction).
Fig. 6: Circulating pump U4847
Installation positions
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