Low
P35 on Alpha Pro Tec Plus

Your boiler is temporarily waiting to start because it is part of a larger heating system setup where multiple units are programmed to ignite in a specific sequence to avoid overloading the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Cascade delay

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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