Medium
E50 on Main Combi 28

Your boiler is struggling to accurately measure the temperature of the water used for your taps, causing it to stop heating your 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

Hot Water NTC Fault

From this model's manual
Verified against the Main Combi 28 installation & service manual, page 51.
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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E28View →E110View →

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