The control unit regulates the operation of the heater and controls the combustion process in accordance with the readings of the flame sensors, air temperature at the inlet and outlet of the heater, the position of the thermostat handle. Built-in temperature sensor can be replaced by an external one. If a malfunction occurs, the control unit diagnoses the heater and issues a malfunction code. Depending on the configuration of the heater, on the display of the combi-timer (in the form of numbers) or on the switch indicator (in the form of a block code - blinking). In addition, the heater can be diagnosed using a diagnostic adapter and a PC. (see relevant instructions).
1. Remove the heater.
2. Disassemble the housing.
3. Disconnect all plugs on the control unit.
4. Unscrew the screws.
5. Slide the control unit in the direction of the blower and pull it up.
6. Work with the removed components.
Note: The repair control unit is not subject to maintenance!
1. Slide the control unit onto the air blower, slide it in the direction of the heat exchanger and fasten with screws.
2. Tighten the screws with a torque of 3.0 + 0.3 Nm.
3. Connect all connectors on the control unit.
4. Assemble the hull.
5. Install the heater.
6. Check the CO2 level and adjust if necessary.