Buderus Gas Boiler Error Codes list

-A - The machine is in the "chimney sweep" mode. After 15 minutes, the "chimney sweep" mode is automatically deactivated

 

-H - Buderus boiler is in heating mode.

 

(=) H - DHW unit

 

0A - Clocking active: the delay time has elapsed between the burner shutdown and start (service function 2.3b).

 

0A - Duration of hot support for GB072-24K: the time interval for maintaining hot water is not yet exhausted (service function 2.3F).

 

0C - Burner starts

 

0E - The heat demand is less than the minimum heat output of the boiler. The boiler operates in on-off mode.

 

0H - The device is in the ready state, there is no need for heat.

 

0L - Gas fittings open, first delay time.

 

0U - The boiler starts.

 

0Y - The actual flow temperature is higher than the set temperature. The boiler switches off.

 

2E - Error: The deaeration function is active.

 

2H - The heating circuit pump and the three-way valve are actively protected against jamming.

 

2P - Gradient limitation: too rapid temperature rise in hot water mode.

 

5H - Boiler test with control system

 

H11 - Damage to the DHW temperature sensor (GB072-24K)

 

Remove the temperature sensor.

Check it, and if it is defective, replace

Check the connecting cable for an open and short circuit, replace if damaged.

0Y - The temperature at the flow sensor is more than 95 ° C.

 

This message may appear in the absence of a malfunction if all valves on the radiators are suddenly closed or after the hot water is removed from the GB072-24K.

Check the working pressure in the heating system. Open the service valves.

Electrical connection of the heating circuit pump to the main controller BC20.

Rotate or replace the heating circuit pump.

Correctly set the power of the pump or its characteristic and reconcile with maximum power.

Check for damage or short circuit to the flow temperature sensor and its wire, replace if necessary.

 

0Y - High temperature on the hot water temperature sensor

 

Check the correct position of the sensor.

Check it, and if it is defective, replace

Insert the KIM correctly, replace if necessary.

 

2P - Gradient limitation: too rapid temperature rise in heating mode

 

Check the working pressure in the heating system. Open the service valves.

Electrical connection of the heating circuit pump to the main controller BC20.

Rotate or replace the heating circuit pump.

Correctly set the power of the pump or its characteristic and reconcile with maximum power.

 

3A - The fan does not work. Check it, and if it is defective, replace

 

3F - The burner and fan have been operating for 24 hours without interruption and are switched off for a short time for safety reasons.

 

4C - The heat exchanger temperature limiter or the limiter of the flue gas temperature of the Buderus boiler has tripped. If the blocking fault exists for a long time, then it goes into a locking fault.

 

4U - Flow temperature sensor is faulty (short circuit). If the fault persists for a long time, the display shows fault code 4U and operating code 222

 

4Y - The flow temperature sensor (break) is defective. If the fault exists for a long time, the display shows fault code 4Y and operating code 223

 

6A - No flame detected. After the 4th ignition attempt, the blocking fault goes into the locking.

 

6L - No ionisation signal during burner operation. The burner is restarted. If ignition is unsuccessful, the blocking error 6A will be shown, after the 4th ignition attempt the blocking fault goes into fault

8Y - The AT90 temperature monitoring relay has tripped. Check the adjustment of the AT90 temperature monitoring relay. Check the setting of the heating control.

 

8Y - The temperature monitoring relay AT90 is faulty. Check for damage or short circuit to the temperature sensor and its wire, replace if necessary.

 

8Y - There is no jumper between the terminals of a separate AT90 temperature monitoring relay.

If the temperature control relay is not connected, then install a jumper

 

8Y - Temperature monitoring relay blocked

Unlock the temperature control relay. Check condensate drain.

The condensate pump does not work - Replace the condensate pump.

 

EL - Defective main controller BC20 - Replace

 

3C - Error operating the fan. Check the fan and its cable with a plug, replace if necessary.

 

3L - The fan has shut down during the delay time. Check and, if necessary, replace.

 

3P - The fan is too slow. Check and, if necessary, replace.

 

3Y - The fan is running too fast. Check and, if necessary, replace. Check the flue gas system and clean or repair if necessary.

 

4C - Error of temperature limiter for heat exchanger or limiter for flue gas temperature.

Check: the presence of damage to the heat exchanger / flue gas temperature limiter and its connecting cable, replace the operating pressure in the heating system, the temperature limiter if necessary, replace the pump head, if necessary replace the pump, fuse, replace if necessary.

Bleed the boiler. Check the water circuit of the heat exchanger, replace if necessary.

For Buderus boilers with a splitter in the heat exchanger, check whether the splitter is installed.

 

4U - Flow temperature sensor is faulty (short circuit). Check for damage or short circuit to the temperature sensor and its wire, replace if necessary.

 

4Y - The flow temperature sensor (break) is defective. Check for damage or breakage of the temperature sensor and its wire, replace if necessary.

 

6A - Error: no flame found.

Check: the connection of the protective conductor, the gas tap is open, the gas pressure is being supplied, the connection to the mains, the electrodes with wires, the flue gas system, if necessary, clean or repair. Check the air / gas ratio, correct if necessary. For natural gas: check the gas flow monitoring relay, replace if necessary. When working with the intake of air for combustion from the room, check the air supply to the room and the ventilation openings.

Clean the drain of the condensate siphon. Remove the diaphragm in the fan mixer, check for cracks and dirt on it. Clean the boiler exchanger Buderus.

Check the gas fitting, replace if necessary. Insert the KIM correctly, replace if necessary. Two-phase network (IT): Set the resistance to 2 ohms between PE and N when connecting the electronic board to the mains.

 

6C - In shutdown mode, the boiler registers a flame.

Check the contamination of the electrodes, replace if necessary.

Check the flue gas system and clean or repair if necessary.

Check the humidity of the electronic board, dry as necessary.

 

6C - A flame was detected after the gas supply was cut off.

Check the gas fitting, replace if necessary. Clean the condensate siphon.

Check the electrodes and connecting wires, replace if necessary.

Check the flue gas system and clean or repair if necessary.

 

7L - Time error for the first delay time. Replace the main regulator BC20.

 

7L - Time error when attempting to restart. Replace the main regulator BC20.

 

9L - Defective coil or connecting wire of gas fittings

Check the wires, replace if necessary. Replace the gas fittings.

 

9L - Faulty gas fitting

Check the wires, replace if necessary. Replace the gas fittings.

 

9P - KIM is not recognized. Insert the KIM correctly, replace if necessary.

 

EL - KIM defective or main controller BC20. Replace KIM. Replace the main regulator BC20.

1. The burner does not turn on

 

The emergency switch of the heating system is set to Off - Enable.

The start switch of the control system is in the OFF position.

Defective protective devices - Check their operability, if necessary, replace the defective machine. Damaged boiler water temperature regulator - Check and, if required, replace defective parts. Damaged safety temperature limiter - Check and, if required, replace defective parts.

 

Error message from external safety devices (eg from a safety device for monitoring the water level) - The user must check the Buderus boiler, repair the fault and, if necessary, replace the element

 

The flue gas monitoring system has worked - AW 10: Release the flue gas monitoring system. AW 50: Wait for a maximum of 15 minutes. The boiler will turn on automatically if a request for heat is received. In case of multiple triggering, check the flue gas path and check the efficiency of the flue gas monitoring system. If there is a defect, then replace it.

 

2. The burner starts and switches to fault. There is no spark during ignition.

 

Is there sound when the spark is generated when the ignition cable is removed? - If not, then: replace the ignition transformer. If so, replace the ignition electrode or ignition burner.

 

3. The burner starts and switches to fault.

 

All gas shut-off valves are closed - Open gas shut-off valves.

The feed pressure of natural gas is more than 8 mbar. If not, then: establish the cause and repair the malfunction. Is the air removed from the pipeline? - Ventilate the air until the gas is released.

 

4. The Buderus boiler burner starts and switches to a fault. There is no ionization current.

 

If the N and L connections are reconnected, - Resolve the error.

Is there a voltage between L and PE? - If not, then: Carry out the PE grounding, in this case install the isolating transformer. Poor ionization wire contact - Eliminate the error, in this case replace the defective part. Short to ground on ionization electrode - Repair damage. Burner flame defect - Replace the element.

 

5. The burner starts and switches to fault. The ionization current is less than 1.5 mA.

 

The core or ceramic of the ionization electrode is dirty - Clean the ionization electrode, if necessary, replace the pilot burner.

 

6. Sounds of boiling

 

Lime deposits or scale formation in the boiler - Clean the water circuit of the boiler in accordance with the manufacturer's recommendations. With constant loss of water, establish and eliminate the cause. If necessary, conduct water treatment and install a dirt trap.