Medium
40 on Baxi 818 System

Your boiler has temporarily stopped because it detected a problem with the temperature readings between the flow and return pipes.

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

Flow - return sensor temperature test

From this model's manual
Verified against the Baxi/Baxi Bmgc Baxi 824 System Fbm 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.

DIY fix possible

Switch the boiler off at the fused spur or mains supply.Wait approximately 30 to 60 seconds for the system to fully reset.Turn the boiler back on and check if the error clears once it attempts to fire.

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Related fault codes

E110View →E119View →E133View →

All 17 fault codes on the 818 System

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

09152028109110118125128130133134135160321384

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