High
27 on Baxi System 60/100

Your boiler has stopped working because it either doesn't have enough water inside the system to operate safely or the internal water pump is failing to move the water around.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Fault on Pump or Low System Pressure

From this model's manual
Verified against the Baxi/Baxi Combi Instant 80 105 He Combi installation & service manual, page 6.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 29 fault codes on the System 60/100

Seeing a different code? Every code this model can display, in one place.

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