High
No light (DHW cold) on Halstead Dimplex Combi

Your boiler is failing to detect when you turn on the hot tap, meaning it isn't heating the water for your shower or taps.

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

Defective DHW flow switch or defective DHW/CH thermistor

From this model's manual
Verified against the Halstead Dimplex Combi 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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Boiler cover options

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