Loss of water indicating light High

Saunier Duval Loss of water indicating light Fault Code

Q: What does the Saunier Duval Loss of water indicating light fault code mean?

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

Q: How much does it cost to fix Saunier Duval error code Loss of water indicating light?

Typical repair cost for the Saunier Duval Loss of water indicating light fault is £0-£120 including labour.

Also written as LOSSOFWATERINDICATINGLIGHT — same fault.

The Saunier Duval Loss of water indicating light fault code means: your boiler has stopped working because the water pressure inside the heating system has dropped too low.. It appears on 1 Saunier Duval model in our database.

Technical description: Indicates that the system pressure has dropped or there is a loss of water in the system (pressure gauge less than 1 bar).

Typical repair cost £0-£120 (including labour)

DIY fix possible

Locate the filling loop (usually a silver braided hose with one or two valves) underneath the boiler.Slowly open the valve(s) to allow mains water into the system while watching the pressure gauge.Close the valve(s) tightly once the needle reaches 1.5 bar.Restart your boiler.

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Saunier Duval models that show the Loss of water indicating light fault code

Click a model for the full fault code list and model-specific repair notes.

Sylva Repair: £0-£120

Source

Saunier Duval Loss of water indicating light fault code information on this page is sourced and cross-checked against the official Saunier Duval service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026