Medium
P18 on Alpha Pro Tec Plus

Your boiler is struggling to keep your hot water at the correct temperature, which may result in lukewarm or inconsistent hot water taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

DHW reheat temp.

From this model's manual
Verified against the Alpha Pro Tec 24 installation & service manual, page 36.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

P17View →P19View →

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