Medium
34 on Remeha W40

Your boiler has detected an issue with a temperature sensor that measures the water returning to the system, causing it to temporarily pause heating to protect itself.

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

Temp.sensor fout Retourtemperatuursensor niet aangesloten of defect.

From this model's manual
Verified against the Remeha/Remeha W40 60 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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Related fault codes

33View →35View →

All 19 fault codes on the W40

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

012456789101219203132334344

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