Cabin Heater: Operation: Heating

During the automatically controlled heating operation, when the coolant temperature reaches 76°C (169°F), the heater will switch to a part load operation. When the coolant temperature reaches 83°C (181°F) or if the heater runs for longer than 76 minutes the heater will switch to a control idle period. If the coolant temperature drops to 73°C (163°F) during a control idle period, the heater will perform a regular starting sequence into full load operation. A drop in coolant temperature to 66°C (151°F) during part load operation will cause the heater to switch to a full load operation.