Low
S.31 on Heatline Monza

Your boiler is currently set to only provide hot water and will not heat your radiators.

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

"Hot water only" mode

From this model's manual
Verified against the Heatline Monza 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.

DIY fix possible

Check your external heating programmer or room thermostat to ensure it is set to the 'On' position and the heating schedule is active.Increase the temperature setting on your room thermostat to see if the heating triggers.Check if the winter/summer mode setting has been accidentally changed on your boiler's control panel.

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