High
1 red flash on Baxi 100/2 HE Plus

Your boiler has sensed that it is getting too hot or that water isn't moving through the system properly, causing it to shut down for safety.

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

Sensor error, temperature fault or flow fault.

From this model's manual
This code was read directly from the manufacturer service manual for this model.
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

2 red flashesView →

All 22 fault codes on the 100/2 HE Plus

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

1 green flash2 red flashes3 green flashes3 red flashes4 green flashes4 red flashes5 green flashes5 red flashes6 green flashes6 red flashes110125160CN12FLASH FLASH ONFLASH OFF ONFLASH ON FLASHFLASH ON ONON FLASH FLASHON FLASH ONON ON FLASH

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