Low
S.76 on Glow-worm Sustain 12s

Your boiler is reminding you that it is time to check and adjust the water pressure in your heating system to ensure it continues running efficiently.

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

Maintenance message: Check the water pressure

From this model's manual
Verified against the Glow Worm Sustain 12s installation & service manual, page 33.
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

Locate the filling loop under the boiler, which usually consists of a silver braided hose with one or two valves.Slowly open the valves to allow water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valves tightly and ensure the pressure remains stable.

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