Boiler displays E10, pressure gauge shows very low or zero pressure, boiler will not fire.

Safety: Allow the system to cool before topping up. Do not over-pressurise.

User procedure:

• Locate the filling loop on your EHC boiler or nearby pipework (usually a braided hose with two valves).
• Open both valves slowly and watch the pressure gauge rise to 1.0–1.5 bar.
• Close both valves firmly and reset the boiler.
• Check for visible leaks around radiators, valves and under the boiler. If pressure drops again, a leak must be found and repaired.

Engineer checks:

• Test the pressure sensor or switch for correct operation.
• Inspect the expansion vessel charge; recharge or replace if failed, as this can cause frequent pressure loss.

If you are unsure how to use the filling loop, consult the EHC manual or a heating engineer.