Medium
H20-986 on Ideal Mini S15

Your boiler has detected trapped air inside the system, which is preventing water from circulating correctly to provide you with heating and hot water.

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

Automatic air purger valve

From this model's manual
Verified against the Ideal Mini He 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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