High
E3 on Main Eco Elite

Your boiler's electronic control centre has developed an internal error and can no longer safely operate the system.

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

Printed circuit board (PCB) fault

From this model's manual
Verified against the Main/Main Eco Elite 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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Boiler cover options

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All 37 fault codes on the Eco Elite

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

1 green flash1 red flash2 red flashes3 green flashes3 red flashes4 green flashes4 red flashes5 green flashes5 red flashes6 green flashes6 red flashes110119125127133160E1E2E20E28E50E110E119E125E133E160FLASH FLASH ONFLASH OFF FLASHFLASH OFF ONFLASH ON FLASHFLASH ON ONON FLASH FLASHON FLASH ONON OFF FLASHON ON FLASH

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