High
Red LED on only on Potterton Suprima HE

Your boiler has lost the signal that tells it to turn on, or a internal electrical component is preventing it from starting.

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

Check external controls/SW LIVE supply or internal fuse/overcurrent fault (Fan or Pump)

From this model's manual
Verified against the Potterton Boiler Suprima 100 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

Flashing RedView →

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 onLockout (Red) light will flashNo Switched LiveONOverheatOverheat - Red LED: FLASHINGOverheat conditionOverheat LOCKOUTOverheat ThermostatPCB FaultRED & GREEN lights flashingRED & GREEN lights OFFRed LED flashingRED LED on continuouslyRed LED rapid flashingRed LED: Flashing RedRed LED: Rapid FlashingRed light flashing (Lockout)THERMISTOR

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