Medium
100 on Baxi Assure

Your boiler is currently running at its absolute maximum capacity and is not modulating down as it should.

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

Maximum output

From this model's manual
Verified against the Baxi Assure installation & service manual, page 50.
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

A cover plan would handle faults like 100: no call-out fees, no surprise bills.

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