Boiler Fault Codes & Errors

• Please contact us as this will require a visit from an engineer.

• Turn your thermostat to its maximum position and check if a C appears on the boiler display. If the boiler fires and the radiators come on, this means the room thermostat wasn't set higher than the room temperature.
• If the boiler still doesn't fire, please contact us as this will require a visit from an engineer

• Rotate all knobs fully clockwise
• Turn the boiler off
• Turn the boiler back on and then press restart

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code L4 as this will require a visit from an engineer.

• The boiler has been reset too many times in 15 minutes.
• Turn the power to the boiler on and off again to reset

• Please contact the installer

• The flow and return differential is wrong and may have been installed correctly / possible crossed pipes.
• Please contact the installer

• The difference between the water flow and return is too high (more than 50⁰)
• Turn the boiler off and bleed/let out the air of your radiators. Ensure the boiler pressure is still at 1 to 1.5 BAR and turn the boiler back on. 
• Possible blockage, please contact us quoting error code FU (we won't take offence) as this will require a visit from an engineer.

View our video on how to top up your boiler pressure:

• Turn the boiler off and bleed/let out the air of your radiators. Ensure the boiler pressure is still at 1 to 1.5 BAR and turn the boiler back on.
• Your central heating pump may not be running. Gently touch it and if it's working properly, there should be a gentle vibration and it should also be warm
• If you believe the central heating pump is NOT running, contact your installer.
• If you believe the central heating pump is running, please contact us quoting error code FA as this will require a visit from an engineer.

View our video on how to top up your boiler pressure:

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code C0 as this will require a visit from an engineer.

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code C2 as this will require a visit from an engineer.

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code F0 as this will require a visit from an engineer.

• Voltage to the boiler may be too low
• Contact a local electrician to inspect the electrics of your property

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code F6 as this will require a visit from an engineer.

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code F5 as this will require a visit from an engineer.

• Reset the boiler

• If this does not fix the problem, please contact us quoting error code F4 as this will require a visit from an engineer.

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code F3 as this will require a visit from an engineer.

• Reset the boiler
• If your gas meter is pay-as-you-go, check there is credit available
• Check other gas powered items in your home, if these are also not working, you should contact a local gas engineer
• Check that the yellow gas isolation valve under the boiler hasn't been turned off. If it is on, the handle/knob will be in pointing in the direction of the pipe.
• If the boiler is making a gurgling/garglign noise whilst trying to fire, please contact your installer as there may be a blockage
• If this does not fix the problem, call us quoting Error Code F2

• Water pressure is too low in the system and will require topping up to between 1 bar and 1.5 bar. 

View our video on how to top up your boiler pressure:

• Reset the boiler
• If this does not fix the problem, please contact us quoting error code L6 as this will require a visit from an engineer.

Restart the boiler: Press and hold the restart button for a minimum of five seconds, then release. Do not try to do more than five restarts in 15 minutes or less because you will see an LC code.

If this does not fix the problem, please speak to Ideal Heating on 01482 498660 or use the live chat option to talk to one of our representatives. Please quote Fault Code F5 because a Gas Safe registered engineer will want to visit the property.

You can find more information on fault codes in the boiler user guides. They are available in paper copy, or pdf from our website: https://idealheating.com/user-guides.

• Check that the water pressure to the boiler is at 1 to 1.5 BAR.
• Check that the yellow gas isolation valve under the boiler hasn't been turned off. If it is on, the handle/knob will be in pointing in the direction of the pipe
• Turn the boiler off and bleed/let out the air of your radiators. Ensure the boiler pressure is still between 1 bar to 1.5 bar and turn the boiler back on
• Press the reset button
• If this does not fix the problem, please contact us quoting error code L3

View our video on how to top up your boiler pressure:

• Reset the boiler
• If your gas meter is pay-as-you-go, check there is credit available
• Check other gas powered items in your home, if these are also not working, you should contact a local gas engineer
• Check that the yellow gas isolation valve under the boiler hasn't been turned off. If it is on, the handle/knob will be in pointing in the direction of the pipe.
• If the boiler is making a gurgling/gargling noise whilst trying to fire, please contact your installer as there may be a blockage
• If this does not fix the problem, call us quoting Error Code L2

Ensure that all radiator valves are open. Check that the water pressure to the boiler is between 1 bar to 1.5 bar. View our video on how to top up your boiler pressure here.Reset the boilerIf this does not fix the problem, please

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