BoilerFaultCodesYour boiler's gas valve is not opening or functioning correctly, preventing the system from producing heat 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: Main valve
What causes this fault?
This fault occurs when the boiler's control system attempts to ignite the burner but detects that the gas valve has failed to open. The most common reason is an electrical failure within the valve's internal motor or a communication error from the main circuit board that prevents the flow of gas.
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 EE5 — no call-out fees, no surprises.
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Worcester Bosch WR325 RSF is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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