GF83.70-P-4205T STH Switchover Valve Component Description

GF83.70-P-4205T STH Switchover Valve Component Description
- with CODE (228) Stationary heater

Component Identification:

Location
The switchover valve on the STH heater unit (A6) is located in the front area of the right wheel well.

Function
The switchover valve is a solenoid valve which, depending on actuation from the STH control unit (A6n1), regulates the flow of coolant (large or small coolant circuit).

Coolant temperature less than 60 °C (heater operation started)
The switchover valve is permanently actuated and thus only releases the small coolant circuit.

Coolant temperature as of 60 °C (heater operation started)
The switchover valve is actuated by pulses. With this, the large coolant circuit is also heated.

No heater operation:
The switchover valve is opened (not actuated) and releases the large coolant circuit.