Low
26.0 on Grant Vortex Pro 15-26

Your boiler is currently operating at its highest possible power setting to meet the heat demand requested by your thermostat.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Maximum heat output (Kerosene) (kW)

From this model's manual
Verified against the Grant/Grant Vortex Pro 15 26 installation & service manual, page 6.
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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All 9 fault codes on the Vortex Pro 15-26

Seeing a different code? Every code this model can display, in one place.

21.036.0A1.2Constant RedFlashes redFlashes red/greenLED offRed

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