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Ideal Boiler Fault Codes

Fault code Fault

F1

Low water pressure - you can manually reset your boiler pressure

F2

Flame loss

F3

Fan fault 

F4 / L4

Flow thermistor 

F5 / L5

Return thermistor

F6

Outside sensor failure 

F7

Low mains voltage 

F9 / L9

Unconfigured PCB

L1

Flow temp too high or no water flow - you can manually set the flow temperature to the lowest setting if this doesn't work we recommend getting an engineer

L2

Ignition lockout - you can manually fix this with our frozen condensate guide here

L6

False flame lockout - reset your boiler and this should fix the issue

LC

5 boiler resets in 15 minutes - turn the electricity to your boiler off then on to fix the issue

FA

Negative differential flow/return rate 

FU

Flow/return differential > 50°C 

DU

Diverter valve in mid-position for service - turn all of the knobs clockwise, turn the boiler off and on, then click restart

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Safety Warning

When your Ideal boiler error codes or fault lights flash, don’t do any repair work that involves working with gas as you are required to be Gas Safe Registered by law.

Here at Boiler Plan all our engineers are Gas Safe Registered and will do an amazing job with any Ideal boiler repair work you may need.

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