BoilerFaultCodesYour boiler has paused operation because it has detected a specific internal fault which it is displaying through a series of alternating flashes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler is blocking for a specific error, display will be blinking alternating with a number and letter to show what kind error is detected
What causes this fault?
This fault occurs when the boiler’s internal computer detects a specific component failure and enters a protective shutdown mode to prevent damage. It is typically caused by a failure in the ignition process, an electrical fault on the main control board, or the fan being unable to clear waste gases safely. Because the 'H' code is a general blocking signal, it usually precedes a more specific sub-code that identifies the exact part at fault.
DIY fix possible
Locate the reset knob on the front control panelTurn the knob to the 'RESET' position and hold for 2 secondsReturn the knob to your desired temperature setting and wait for the boiler to restart
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like H — no call-out fees, no surprises.
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Ideal Classic M3050 M5080 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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