How much does it cost to fix Grant error code DHW PUMP (FLASHING)?

Typical repair cost for the Grant DHW PUMP (FLASHING) fault is £150-300 including labour.

DHW PUMP (FLASHING) High

Grant DHW PUMP (FLASHING) Fault Code

Q: What does the Grant DHW PUMP (FLASHING) fault code mean?

Your boiler is struggling to detect the temperature of your hot water supply, which means it will likely stop heating your water until a faulty sensor or internal control board is replaced.

Also written as DHWPUMPFLASHING — same fault.

The Grant DHW PUMP (FLASHING) fault code means: your boiler is struggling to detect the temperature of your hot water supply, which means it will likely stop heating your water until a faulty sensor or internal control board is replaced.. It appears on 5 Grant models in our database.

Technical description: Indicates either a ‘Store’ thermistor or PCB fault.

Typical repair cost £150-300 (including labour)

Engineer required

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

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Grant models that show the DHW PUMP (FLASHING) fault code

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

Source

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

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