BoilerFaultCodes.com

Glow-worm Xtramax Fault Codes

Combi Natural GasLPG 12.2-30.2 kW 2005-2009 Discontinued
GC Number: 47-047-23

Replaced by: Energy Store

This boiler uses LED flash patterns

Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →

Most common fault codes

02
Your boiler has detected an issue with how it breathes, meaning it cannot safely remove exhaust fumes or pull in fresh air.
Gas Safe engineer required · £120-350
04
Your boiler has failed to light the gas flame after several attempts, which means you will not have any heating or hot water until it is fixed.
May be DIY safe · £120-£350
05
Your boiler has shut down because it is getting too hot inside, likely due to water not flowing properly through the system.
May be DIY safe · £120-£350

All 29 fault codes

Code Severity Plain English
00 Low Your boiler is operating normally and there are currently no faults detected within the system.
02 High Your boiler has detected an issue with how it breathes, meaning it cannot safely remove exhaust fumes or pull in fresh air.
04 High Your boiler has failed to light the gas flame after several attempts, which means you will not have any heating or hot water until it is fixed.
05 High Your boiler has shut down because it is getting too hot inside, likely due to water not flowing properly through the system.
06 High Your boiler has detected a fault with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot safely regulate heat.
07 Medium Your boiler's temperature sensor for hot water has stopped working correctly, meaning your system cannot tell how hot the water is.
08 High Your boiler's hot water storage tank sensor has developed a fault and can no longer accurately read the water temperature.
09 High Your boiler has lost its ability to monitor water pressure because the internal sensor has developed an electrical fault.
12 High Your boiler's control panel has likely detected moisture or dampness inside the screen or buttons, preventing it from working correctly.
13 High Your boiler's internal computer has encountered a communication error or has failed, which means it cannot tell the boiler how to operate safely.
14 High Your boiler has likely overheated because the water isn't moving through the system properly or a sensor has detected an unsafe temperature.
15 High Your boiler's gas control mechanism has stopped moving correctly, which means the system cannot safely regulate the fuel it needs to stay alight.
16 Emergency Your boiler has detected that gas is continuing to flow when it should have stopped, which is a significant safety concern.
17 High Your boiler is not receiving enough electrical power to operate safely, which is preventing it from heating your water.
20 High Your boiler is having trouble sending signals between its internal electrical parts, which is preventing it from working correctly.
21 High Your boiler has lost water pressure and does not have enough water inside it to operate safely.
F0 High Your boiler has stopped working because the water pressure is too low for the system to run safely.
F1 High Your boiler is not receiving gas or providing a spark, which means it cannot light the flame needed to provide heating and hot water.
F2 High Your boiler has stopped working because a sensor that measures the temperature of the water leaving the unit has failed or disconnected.
F3 High Your boiler has shut down because it is getting too hot inside, likely because water isn't moving through the system properly.
F4 Medium Your boiler's temperature sensor for hot water has stopped working correctly, meaning your taps and showers may not get warm.
F5 High Your boiler has switched itself off because it has reached an unsafe temperature to prevent internal damage.
F6 Low Your boiler is having trouble communicating with the outdoor temperature sensor, which helps it run more efficiently based on the weather.
F7 Medium Your boiler has lost its ability to monitor the temperature of the stored hot water, meaning you may have lukewarm water or no hot water at all.
F8 High Your boiler is struggling to push water around the system, often due to a blockage in narrow pipes or a pump that isn't working correctly.
F9 High Your boiler has stopped working because it cannot correctly detect the water pressure in the system.
F9 to F0 Low Your boiler is displaying its recent history of errors to help a technician understand what has gone wrong in the past.
Flashing 0.3 bar High Your boiler’s water levels have dropped too low for it to start up safely.
Pictogram of a spark High Your boiler is failing to light because it isn't receiving a steady flow of gas.

Glow-worm Xtramax 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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