High
46 on Alpha E-Tec Plus 28NX

Your boiler has temporarily stopped working because it detected that the water inside got too hot.

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

Intervention of DIM v2 safety thermostat or low temperature safety thermostat outside the boiler - During normal operation, if an anomaly causes excessive overheating of the flow temperature in low temperature conditions, the boiler blocks

From this model's manual
Verified against the Alpha/Alpha E Tec Plus Nx 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 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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Related fault codes

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All 37 fault codes on the E-Tec Plus 28NX

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

01020304050607081015162023242729313637384344454748495160617075768398138139

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