Unknown
1 flash red on Potterton Ultra 12 Heat

Potterton Ultra 12 Heat fault code 1 flash red

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Sensor error: Bad connection to flow or return temperature sensor, Fault with flow or return temperature sensor(s), Low or no flow through boiler, Reverse flow through boiler

From this model's manual
Verified against the Potterton/Potterton Ultra 12 Heat 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 12 fault codes on the Ultra 12 Heat

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

1 flash green2 flashes green2 flashes red3 flashes green3 flashes red4 flashes green4 flashes red5 flashes green5 flashes red6 flashes green6 flashes red

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