BoilerFaultCodesWhat the manual says
Manufacturer manualDefective control panel.
Shared across the Maximiser SE range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the boiler's internal computer chips or electrical circuits suffer a hardware failure, meaning the different components can no longer talk to each other. The most common reason is general wear and tear of the electronic capacitors over time, or an electrical surge that has damaged the delicate tracking on the circuit board.
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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All 118 fault codes on the Maximiser SE
Seeing a different code? Every code this model can display, in one place.
-. / A-. / H-. / Y-. H=. / H=. H0 / A0 / H0 / Y0 or -. / H0A0H0L0U0Y001011 / C1C2 / C2 / F2 / P2 / U2C2F2P2U030044 / A4 / C4 / F4 / L4 / P4 / U4 / Y4A4C4F4L4P4U4Y005055 / A5 / Y5A5Y6 / A6 / C6 / H6 / L6A6C6H6L7 / A7A7C7F7H7L0088L9A9C9F9H9L9P9U0101001112131415016160171718018192021232425262728290293031323435363738394041041424360EAEFEHELEPNo display