BoilerFaultCodes.com

Daikin D2CND Fault Codes

Combi Natural GasLPG 24-35 kW 2017-present
GC Numbers: 47-439-0147-439-0247-439-03

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Most common fault codes

1J-64
Your boiler has shut down because it has detected it is getting too hot, often due to low water pressure or poor circulation.
May be DIY safe · £100-250
8A-46
Your boiler has detected that the water inside it is too cold and has switched itself off to prevent internal pipes from freezing and bursting.
May be DIY safe · £0-120
8H-65
The water inside your boiler is heating up too quickly because it cannot flow through your radiators properly.
May be DIY safe · £0-120

All 46 fault codes

Code Severity Plain English
1J-64 High Your boiler has shut down because it has detected it is getting too hot, often due to low water pressure or poor circulation.
8A-46 High Your boiler has detected that the water inside it is too cold and has switched itself off to prevent internal pipes from freezing and bursting.
8H-65 High The water inside your boiler is heating up too quickly because it cannot flow through your radiators properly.
10-64 High Your boiler has detected a communication issue with its internal gas control system and has shut down as a safety precaution.
10-65 High Your boiler has detected an electrical issue with the gas control system and has shut down as a safety precaution.
11-64 High Your boiler is having trouble lighting the gas to start the heating process and may need to be restarted.
11-65 High Your boiler is struggling to keep the flame steady and will keep trying to restart itself until it succeeds.
11-66 High Your boiler is struggling to light or recognize that a flame has started, causing it to shut down for safety after several failed attempts.
11-67 Low Your boiler has temporarily lost its flame while running and is attempting to restart itself automatically.
12-64 High Your boiler is having trouble managing the flame correctly and has locked itself for safety after failing to stabilise.
12-65 High Your boiler is having trouble starting the burner safely and needs a simple restart to clear a temporary electronic glitch.
12-66 Low Your boiler is having trouble detecting the steady flame it needs to run safely, but it may just be a temporary sensing error.
12-67 High Your boiler's flame sensor is detecting an unusual reading that is outside of its normal operating range, which has caused the system to stop as a safety precaution.
12-68 High Your boiler has failed to correctly detect its own flame during start-up, likely due to a minor sensor reading inconsistency.
12-69 High Your boiler is struggling to automatically adjust its internal settings to ensure the gas burns efficiently, which may lead to it shutting down for safety.
13-64 / 13-65 High Your boiler's fan is not spinning at the correct speed to safely clear waste gases, causing the system to shut down for safety.
16-64 Emergency Your boiler has shut down because the exhaust gases are getting too hot, indicating a potential blockage or safety issue in the flue pipe.
80-01 High Your boiler has detected a problem with the sensor that monitors the temperature of the water returning to the unit, causing it to stop for safety.
81-01 High Your boiler has detected an issue with the sensor that measures the temperature of the water leaving the unit, which usually results in the system shutting down for safety.
81-65 Low Your boiler is still providing heating and hot water, but it has detected a problem with the temperature sensor for your solar thermal system.
E1-64 High Your boiler has sensed a flame inside the system before it was even supposed to start up, causing it to shut down for safety.
E1-65 High Your boiler's internal electronic self-monitoring system has detected a technical fault and has shut down as a safety precaution.
E1-66 Medium Your boiler is struggling to automatically adjust its internal settings for the burner to stay lit and is attempting to restart itself.
E1-67 High Your boiler has lost its internal settings and needs to be restarted to recalibrate itself.
E1-68 High Your boiler has lost track of the basic flame sensor settings required to run safely and needs to be restarted to recalibrate itself.
E1-69 / E1-70 High Your boiler’s internal computer has encountered a software error while checking its settings, which has caused the system to stop working for safety.
E1-71 High Your boiler has experienced a fundamental electronic control failure that has caused it to lock down for safety.
E1-72 High Your boiler has detected an internal communication error with its ignition system and has locked itself out for safety.
E1-73 High Your boiler's internal computer has encountered a software glitch or a technical hiccup and needs a system restart to try and clear the error.
H9-01 Low Your boiler is struggling to understand the outdoor temperature, which may cause your heating to run less efficiently or at the wrong temperature.
HC-01 Low Your boiler has a fault with the thermometer that measures hot water temperature, meaning your hot water may be unreliable although your heating should still work.
HJ-08 Emergency Your boiler has too much water pressure and needs some drained out to reach a safe operating level.
HJ-09 High Your boiler has detected that the water pressure is too low to operate safely, causing it to shut down temporarily.
HJ-10 High Your boiler has lost the ability to accurately measure the water pressure, which prevents it from operating safely to heat your home.
J6-01 High Your boiler is getting too hot too quickly because water isn't flowing through the system properly or the pressure has dropped too low.
J6-20 High Your boiler has detected that the water returning to the unit is too hot, which has caused it to shut down to prevent damage.
J6-21 Medium Your boiler has detected that the water coming back from your radiators is hotter than the water going out, which usually means there is a blockage or the internal sensors are confused.
JJ-64 High Your boiler is not receiving enough electrical power from your home's mains supply to operate safely.
U2-01 Low Your boiler has detected that the electrical supply coming into the unit is currently too high, which could cause damage to internal parts if left unchecked.
U4-65 Low Your boiler is still providing heat and hot water, but it has lost communication with your smart room thermostat, meaning you cannot control the temperature remotely.
U4-66 High Your boiler's internal components have stopped communicating with each other, meaning the system cannot send or receive the signals needed to run.
U4-67 High Your boiler has experienced a communication error that has stopped it from working, and it requires a manual power reset to clear the internal memory.
UA-64 High Your boiler's computer memory card is experiencing a communication error or has failed during an internal update, causing the system to stop working.
UA-65 High Your boiler's main control board is currently unable to communicate with its internal memory chip and needs a software or hardware synchronisation.
UA-66 High Your boiler's internal memory chips are having trouble communicating with each other, meaning the control board doesn't recognise the boiler's specific settings.
UA-67 High Your boiler is unable to start because it cannot detect its internal memory chip, which contains the essential programming it needs to operate.

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