Boiler displays A10, no burner operation, may indicate low water pressure or flow

Safety: Do not overfill the system. Check for leaks before topping up repeatedly.

• Read pressure: Check the pressure gauge or digital reading on the Hoval boiler. If below the minimum (often 0.8–1.0 bar), top up using the filling loop until within the recommended range.
• Bleed air: After topping up, bleed radiators and the boiler's automatic air vent (if accessible), then recheck pressure.
• Check for leaks: Inspect visible pipework, radiator valves, and the boiler underside for signs of water. Persistent pressure loss indicates a leak that must be repaired.
• Pressure sensor: If pressure is correct but A10 remains, the water pressure sensor may be blocked or faulty. A technician can remove and clean or replace the sensor.