BoilerFaultCodesTechnical description
Boiler fails to work (checks required: Electrical Plugs PL1 to PL6, External Call for Heat, Boiler Temperature Knob, Gas & Water Connections, Main Supply Voltage).
What causes this fault?
This fault occurs when the boiler's internal computer stops the system because it hasn't received the correct electrical signal to start or has detected a failure in the ignition sequence. The most common reasons include a lack of communication from your wall thermostat, a failure in the electronic control board, or a component like the gas valve not opening to allow the flame to light.
This fault is often seen during the first cold snap of autumn when external thermostats are turned up for the first time and older electronic components struggle to handle the sudden demand.
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.