BoilerFaultCodesYour boiler's computer parts are having trouble talking to each other, which means the system cannot operate for heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Communication error with the printed circuit board (PCB)
What causes this fault?
This fault occurs when the boiler's internal control board loses its connection with the sensors and valves that regulate heating. The most common reasons are a loose internal wire connection, moisture getting onto the electronics, or a component failure within the circuit board itself.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like H.03 – .01 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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