BoilerFaultCodesWhat the manual says
Manufacturer manualDisplayed if the boiler fails to light after 5 attempts
From this model's manual
Verified against the Ideal Concord Cxa 40 120 installation & service manual.
What causes this fault?
This fault occurs when the boiler tries to light the gas but cannot detect a stable flame, causing the system to shut down for safety. The most common reasons are that the spark isn't strong enough to ignite the fuel, the sensors are too dirty to 'see' the flame, or the gas valve isn't opening correctly to let fuel into the burner.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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