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7.14.9 Preheating unit
Hotstart preheating unit
1 Plastic cap (outlet)
2 On/Off switch
3 Plastic cap (inlet)
4 Shut-off valve
5 Flow heater
6 Vent valve
7 Thermostat
8 Circulating pump
Cylinders
Rated voltage / frequency
Heat output kW
12V
230V / 50 Hz
9
400V / 50 Hz
9
230 V / 60 Hz
9
440 V / 60Hz
9
16V
230V / 50 Hz
12
400V / 50 Hz
12
230 V / 60 Hz
12
440 V / 60Hz
12
Function
The preheating unit heats up the engine coolant. The circulating pump (8) ensures the circulation of the
preheated engine coolant through the engine.
The flow heater (5) comprises a heating element. The thermostat (7) switches off the preheating unit via
contactors when the engine coolant temperature has reached the setting of the thermostat (7).
In the event of excessive coolant temperature, the temperature limiter of the thermostat (7) opens the
control loop. The preheating unit is switched off.
The unit must be reset manually after the fault has been rectified.
204 | Task Description | MS150066/02E 2013-02
TIM-ID: 0000014749 - 004