BoilerFaultCodes.com

Ideal Concord CXA 40-120 Fault Codes

Regular Natural Gas 11.7-35.2 kW 1994-2004 Discontinued
GC Numbers: 41-391-4541-391-4641-391-4741-391-4841-391-4941-391-5041-391-5141-391-5241-391-53

Replaced by: Concord CXD

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Most common fault codes

Air pressure switch (if fitted)
Your boiler has detected an issue with the air flow or ventilation system, preventing it from firing up safely.
Gas Safe engineer required · £120-280
Boiler sensor
Your boiler has detected an issue with its internal sensors and has stopped running to prevent any damage or incorrect temperature readings.
Gas Safe engineer required · £140-£260
C/H Sensor Fault
Your boiler has lost its ability to accurately measure the temperature of the water being heated for your radiators, causing it to stop running as a safety precaution.
Gas Safe engineer required · £120-190

All 19 fault codes

Code Severity Plain English
Air pressure switch (if fitted) High Your boiler has detected an issue with the air flow or ventilation system, preventing it from firing up safely.
Boiler on Low Your boiler is working normally and the light simply indicates it is switched on and firing.
Boiler sensor High Your boiler has detected an issue with its internal sensors and has stopped running to prevent any damage or incorrect temperature readings.
Burner on Low Your boiler is operating normally and is currently firing to provide heat.
C/H Sensor Fault High Your boiler has lost its ability to accurately measure the temperature of the water being heated for your radiators, causing it to stop running as a safety precaution.
Detection Fault High Your boiler is failing to start because it cannot successfully ignite the gas after several attempts.
Fan (If fitted) High Your boiler's internal air system is failing to move waste gases out of the flue, which is preventing the unit from firing up safely.
Float switch (if fitted) High Your boiler has detected that a safety device designed to prevent water overflow or blockages has been triggered, causing the system to shut down.
GAS VALVE FAULT High Your boiler is unable to safely control the flow of gas needed to stay alight, so it has shut down as a safety precaution.
Gas valve(s) High Your boiler is unable to safely control the flow of gas needed to stay lit, so it has shut down to avoid a potential hazard.
L-01 High Your boiler has tried to fire up five times without success and has shut itself down for safety.
No flow High Your boiler has stopped heating because it cannot detect any water moving through the system to keep it safe.
Outside sensor (if fitted) Low Your boiler has lost connection with its outdoor thermometer, meaning it might struggle to adjust its temperature correctly for the weather.
Overheat High Your boiler has shut itself down as a safety precaution because the water inside has become far too hot.
OVERHEAT FAULT High Your boiler has switched itself off because it became too hot, acting as a safety precaution to prevent damage.
Overheat light High Your boiler has become too hot and has automatically shut down to prevent damage or safety issues.
Pump High Your boiler has detected that water is failing to circulate correctly through the system, which will prevent it from heating your home or providing hot water.
PUMP FAULT High Your boiler is unable to move hot water around the system, meaning your heating and hot water will not work.
Spark generator fault High Your boiler is unable to create the spark needed to light the gas burner, meaning the system cannot fire up to provide heat.

Ideal Concord CXA 40-120 is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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