High
Very fast pulses (4 per second) on Ideal Mini

Your boiler has stopped working because it has detected an issue with water flow, internal temperature, or system pressure.

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.

What the manual says

Manufacturer manual

Faulty boiler or irregular operation as: Empty primary circuit, No primary circuit flow, Lack of burner ignition, Excessive temperature in the primary circuit, Dip-switch 3 left in the OFF position, Faulty temperature probe

From this model's manual
Verified against the Ideal/Ideal Mini He installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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Related fault codes

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All 11 fault codes on the Mini

Seeing a different code? Every code this model can display, in one place.

1 second ON 1 second OFFA short pulse every 4 secondsExcessive temperature on primary circuitFaulty CH temperature probe NTCFaulty DHW temperature probe NTCFaulty primary circuitIgnition gas pressure adjustmentLack of burner ignitionMinimum gas pressure adjustmentN/A

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