BoilerFaultCodes.com
E134 High Lockout

Your boiler is struggling to light because it cannot detect a steady supply of gas or a flame within the required timeframe.

Call an engineer soon

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

Technical description: Elapsed time gas valve open without gas(short request in a short period)

What causes this fault?

This fault occurs when the boiler tries to ignite multiple times but fails to establish a steady flame. The most common reasons are a lack of gas reaching the burner, worn-out spark electrodes that can't light the fuel, or a faulty sensor that fails to tell the boiler the flame is actually lit.

This fault is more frequent during extreme cold snaps, as gas pressure in the external mains can fluctuate or moisture in the external pipework can freeze and restrict flow.

Typical repair cost £120-280 (including labour)

DIY fix possible

Check that your gas emergency control valve is fully open.If you have a prepayment meter, ensure you have sufficient credit.Check if other gas appliances, like a hob, are working to confirm gas supply.Reset the boiler by turning the selector knob to 'R' for five seconds.

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Protect yourself from future repair bills

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