BoilerFaultCodesTechnical description
Pressure too high, boiler off
What causes this fault?
This fault occurs when the water pressure inside your heating system exceeds the safe operating limit of 3.0 bar. The most common reasons are a filling loop valve being left slightly open or the internal expansion vessel losing its air charge, which prevents it from absorbing the natural expansion of water as it heats up.
This issue often surfaces during the first cold spell of autumn when the heating is turned on for the first time in months, causing the water to expand and reveal a failing expansion vessel.
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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