Operating instructions

4. Installation
4.9 Initial Operation
1. Check your installation for:
- loose nuts and bolts.
- exhaust system routing and clamp tightness.
- loose hose clamps.
- routing and securing of wiring and heater hoses.
- kinked or pinched hoses.
- routing and securing of fuel lines.
- battery connection and polarity.
2. Top off or refill cooling system with coolant as per engine manufacturers recommendations.
3. Open shutoff valves.
4. Set heater valve to max. heat position and turn off Air Conditioning in cab and sleeper.
5. Start the vehicle engine and run it at a fast idle for 10 minutes to purge air from the TTC
and the heat exchanger. While the engine is running check:
- hose connections for leaks.
- coolant level in the expansion tank and add coolant as needed.
6. Shut off the engine.
7. Switch on Webasto heater using the toggle switch or the fiInstan Heatf button on timer and check:
- Switch toggle or instant heat button illuminates.
- circulating pump in operation.
- initiation of start up sequence.
- successful start up and operation.
8. Temperature differential between water inlet and outlet should not exceed 10 °C (18 °F).
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Thermo Top C (TTC) 4 Installation
NOTE:
Coolant temperature must be below 86 °F (30 °C) to start up.
NOTE:
Installation with long fuel lines may need a second start attempt to prime the fuel lines. Cycle
ON/OFF switch to reset control unit.
NOTE:
The engine temperature gauge may read lower than actual heater output temperature. This is due
to the location of the temperature gauge sensor on the engine.