High Lockout
52 on Ideal Mexico CF3 40 & 50

Your boiler has managed to start the small pilot flame, but the main burner fails to ignite to provide full heating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

PILOT LIT BUT NO MAINS GAS

What causes this fault?

This fault occurs when the boiler successfully lights the small internal pilot flame but the main burner fails to catch fire. The most common cause is a faulty gas valve that isn't opening properly to let the full flow of gas through, or a blockage in the main injector that delivers fuel to the burner.

This issue is frequently seen during the first cold snap of autumn, as gas valves can become stuck or seized after being inactive throughout the summer months.

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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