Medium
P38 on Alpha Pro Tec Plus

Your boiler is having trouble communicating with the sensors that monitor the temperature of the water circulating through your radiators.

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

CH sensor option

From this model's manual
Verified against the Alpha Pro Tec 24 installation & service manual, page 37.
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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Avoid the next call-out bill

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