High
E3 on Viessmann Vitodens 100-W BPJA 25kW P29

Your boiler has shut itself down as a safety precaution because it has detected a problem with its burner or one of its safety checks, so it can't heat your home or water until a qualified engineer has looked at it.

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

Burner in a fault state – Fault in safety chain.

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 100 W Bpja 5609913 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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Related fault codes

E1View →E2View →F4View →

All 21 fault codes on the Vitodens 100-W BPJA 25kW P29

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

5A3038515259b0b8E5F0F1F2F3F4F8F9FAFCFdFF

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