High
Error 20 on Ideal Evomax 30

Your boiler has temporarily locked out because it mistakenly detects a flame when it shouldn't be burning.

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

False Flame Lockout

From this model's manual
Verified against the Ideal/Ideal Gc No 41 750 38a 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

Error 06View →Error 19View →Error 27View →

All 7 fault codes on the Evomax 30

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

808182838485

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