High
Boiler Fault Finding 8 on Grant Vortex 15-20

Your boiler is failing to get hot enough because it is not receiving the correct amount of fuel or is set up incorrectly, meaning it cannot provide you with heating or hot water.

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.

Technical description

Water temperature low. Undersize nozzle and/or low fuel pressure. Check boiler thermostat and combustion settings.

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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