Medium
DHW PUMP Fast flash on Grant Vortex Eco External Wall Hung

Your boiler is struggling to accurately measure the temperature of the water stored for your taps, causing it to pause heating.

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

Check DHW ‘store’ thermistor connection to PCB. Replace ‘store’ thermistor.

From this model's manual
Verified against the Grant Vortexblue Internal Combi Installer Uk Doc 0131 Rev 1 1 October 2020 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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