Boiler Repairs — Frequently Asked Questions
What does the Worcester Bosch EA fault code mean?
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The Worcester Bosch EA code indicates an ignition lockout — the boiler has tried to ignite but failed. Common causes include a faulty ignition lead or electrode, gas supply issues, or a failing PCB. You can try a single reset by pressing the reset button. If EA returns immediately or repeatedly, call a Gas Safe engineer — repeated ignition attempts can be a safety concern. Warmflame Gas covers Cheadle and can typically attend within 15–30 minutes.
What does the Vaillant F22 fault code mean?
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Vaillant F22 indicates low water pressure in the system — your boiler pressure has dropped below the minimum threshold needed to operate safely. Check the pressure gauge (should read 1–1.5 bar when cold). If it's below 1 bar, try re-pressurising via the filling loop. If pressure keeps dropping within a day or two, there is likely a system leak or failing expansion vessel that needs a Gas Safe engineer to diagnose.
What do Vaillant F28 and F29 fault codes mean?
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F28 on a Vaillant boiler indicates an ignition failure — the boiler cannot establish a flame. F29 means the flame was lit but then went out unexpectedly during operation. Both codes often relate to gas supply problems, a faulty gas valve, or ignition component issues. Check other gas appliances are working first. If gas supply is fine, a Gas Safe engineer is needed. Do not keep resetting without investigation as this will not resolve the underlying cause.
What do Baxi E119 and E133 fault codes mean?
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Baxi E119 is a water pressure fault — the system pressure has dropped too low for safe operation. Re-pressurise the system to 1–1.5 bar. If E119 returns within days, an engineer should investigate for leaks or a failing pressure relief valve. Baxi E133 is an ignition lockout, similar to the Worcester EA code — the boiler cannot establish ignition. Try one reset; if E133 returns, contact a Gas Safe engineer rather than continuing to reset.
What do Ideal L2 and F1 fault codes mean?
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Ideal L2 indicates a flow thermistor fault — a temperature sensor has failed or is reading incorrectly, causing the boiler to shut down as a precaution. This is not a user-resolvable fault and requires a Gas Safe engineer to replace the thermistor. Ideal F1 typically indicates a PCB or internal control fault. Both codes need professional diagnosis — attempting resets will not fix them and may delay resolution.
What do Glow-worm F1 and F4 fault codes mean?
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On Glow-worm boilers, F1 indicates an ignition lockout — the boiler has attempted to light and failed. F4 is a low water pressure fault, indicating the system pressure has dropped. For F1, try a single reset; if the code returns, call an engineer. For F4, re-pressurise the system to 1–1.5 bar via the filling loop. If F4 returns after a few days, there is likely an underlying leak or vessel fault that needs professional attention.
Can I keep resetting my boiler when it shows an error code?
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A single reset is reasonable as a first response to any boiler lockout code. However, if the code returns after resetting, do not keep repeating the process — this will not fix the underlying fault and can mask a more serious issue. For ignition codes (Worcester EA, Baxi E133, Vaillant F28/F29, Glow-worm F1), repeated failed ignition attempts can be a safety concern. Call a Gas Safe engineer if the code persists. Warmflame Gas covers Cheadle and the SK8 area with typical response times of 15–30 minutes.
Have more questions? Call us on 0161 410 9979