❍❍❍❍ (DHW) High

Halstead ❍❍❍❍ (DHW) Fault Code

Also written as DHW — same fault.

The Halstead ❍❍❍❍ (DHW) fault code means: your boiler is failing to detect that you have turned on the hot tap, meaning it cannot provide hot water to your home.. It appears on 6 Halstead models in our database.

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.

Technical description: DHW cold: Defective DHW turbine or Diverter valve
Typical repair cost £150-280 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

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Halstead models that show the ❍❍❍❍ (DHW) fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Halstead ❍❍❍❍ (DHW) fault code information on this page is sourced and cross-checked against the official Halstead service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026