Emergency
2 flashes red on Potterton Apollo

Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage or fire risk.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

High temperature protection: Over-temperature thermostat on heat exchanger activated, No water flow through heat exchanger, Over-temperature thermostat fault, PCB over-temperature condition, Flue fault

From this model's manual
Verified against the Bm Potterton Potterton_Ultra_Heat_compressed 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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Avoid the next call-out bill

A cover plan would handle faults like 2 flashes red: no call-out fees, no surprise bills.

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