Bosch Condens 8300i W Installation And Maintenance Instructions Manual page 48

Troubleshooting
Fault text on the display, description
811 A Hot water heating: thermal disinfection
failed
815 W Low loss header temp. sensor faulty
1010 O No communication via EMS BUS connection 1. Rectify wiring fault and switch the control unit off and on again.
1013 W Max. combustion point reached
1017 W System pressure too low
1018 W Maintenance interval expired
1019 W Incorrect pump type detected
1022 W Cylinder temp. sensor faulty or contact
problems
1023 Maximum run time including standby time
reached
1037 W Outside temp. sensor faulty - heating back-
up operation active
1065 W System pressure sensor faulty or not
connected
1068 W Outside temp. sensor or lambda probe
faulty.
1075 W Heat exchanger temp sensor short circuit
1076 W Heat exchanger temp sensor disconnected 1. Connect the plug to the temperature sensor correctly.
2085 V Internal fault
2908 V System fault boiler electronics / basic
controller
2910 V Fault in flue system
2914 - V Boiler electr. system fault
2916
48
Remedy
1. If water is being drawn constantly, take action to stop this.
2. Position the DHW temperature sensor correctly.
3. Check that there is contact between the DHW cylinder temperature sensor and the
cylinder.
4. Vent the cylinder circuit.
5. Set DHW heating to "priority".
6. Check plate heat exchanger for calcification.
7. Check sizing of DHW circulation line and heat loss.
1. Check hydraulic configuration, correct if necessary.
2. Check sensor for breaks or short circuits, replace if necessary.
2. Repair the BUS cable or replace it.
3. Replace faulty EMS-BUS node.
1. Carry out maintenance.
2. Reset service display.
1. Top up water and vent the system.
2. Check the pressure sensor, replace if necessary.
1. Carry out maintenance.
2. Reset service display.
1. Check pump cabling.
2. Check that the correct heating pump type is in the appliance, replace if necessary.
1. Connect the plug to the temperature sensor correctly.
2. Connect the plug to the control device correctly.
3. Check the temperature sensor, replace if necessary.
4. Check temperature sensor connecting lead, replace if necessary.
1. Carry out maintenance.
2. Reset service display.
1. If an outside temperature sensor is not desired. Select the room temperature-
dependent configuration in the control device.
2. If there is no continuity, rectify the fault.
3. Clean corroded terminals in the outside sensor housing.
4. If values do not match, replace the sensor.
5. If the sensor values matched, but the voltage values do not match, replace the control
unit.
1. Connect the plug to the pressure sensor correctly.
2. Check pressure sensor connecting lead, replace if necessary.
3. Check the pressure sensor, replace if necessary.
1. Connect the plug to the temperature sensor correctly.
2. Connect the plug to the control device correctly.
3. Attach the temperature sensor correctly.
4. Check the temperature sensor, replace if necessary.
5. Check temperature sensor connecting lead, replace if necessary.
1. Connect the plug to the temperature sensor correctly.
2. Check the temperature sensor, replace if necessary.
3. Check temperature sensor connecting lead, replace if necessary.
2. Check the temperature sensor, replace if necessary.
3. Check temperature sensor connecting lead, replace if necessary.
1. Unlock.
2. Disconnect power from the system for 30 seconds.
3. Replace the burner control unit.
If the fault persists following a reset, the burner control unit is faulty and must be replaced.
1. Install the flue system.
2. Remove any deposits from the flue system.
If the fault persists following a reset, the control device is faulty and must be replaced.
Condens 8300i W – 6721841533 (2022/12)