High
Lockout (Red) light will flash on Potterton Suprima HE

Your boiler has detected that it is running too hot and has automatically shut down to prevent damage, meaning you currently have no heating or hot water.

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

An overheat condition has occurred; boiler requires re-setting

From this model's manual
Verified against the Potterton Boiler Suprima 30 80he 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

LockoutView →

All 51 fault codes on the Suprima HE

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

242526272829All lights: OFFAPS Cycling LOCKOUTAPS Stuck FaultBoiler TemperatureCasting Thermistor FaultCirculationCirculation LOCKOUTElectrical Supply FaultFalse Flame FaultFlashing Red LEDFlow Thermistor FaultGreen LED OFF, Red LED ONGREEN LED on continuouslyGreen LED ON, Red LED OFFGreen light 'On' onlyGreen light flashes rapidlyGreen light On onlyIgnition LOCKOUTLights: Flash Flash OnLights: Flash Off FlashLights: Flash Off OnLights: On Off FlashLockoutLockout (LED Mode)Lockout (rapid flashing)Lockout (Red) light is onNo Switched LiveONOverheatOverheat - Red LED: FLASHINGOverheat conditionOverheat LOCKOUTOverheat ThermostatPCB FaultRED & GREEN lights flashingRED & GREEN lights OFFRed LED flashingRED LED on continuouslyRed LED on onlyRed LED rapid flashingRed LED: Flashing RedRed LED: Rapid FlashingRed light flashing (Lockout)THERMISTOR

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