High
Flashing on Potterton Envoy Plus

Your boiler has detected a fault and has safely shut itself 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

Boiler at Lock-Out

From this model's manual
Verified against the Potterton/Potterton Envoy 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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All 24 fault codes on the Envoy Plus

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

Case sensorCase temperatureControl failedDisplay not illuminatedDry fireDry fire sensorFan speedFlame lossFlow sensorHot Surface IgniterLockoutPulse Red (1 flash)Pulse Red (2 flashes)Pulse Red (3 flashes)Pulse Red (4 flashes)Pulse Red (5 flashes)Pulse Red (6 flashes)Return sensorSensorShorted signalShut downStand-byWiring fault

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