A2 displayed, furnace stops, sometimes accompanied by gurgling noises

Safety first: Allow the system to cool before adding water. Do not overpressurise.

• 1. Check pressure gauge: Read the system pressure on the gauge. If below the recommended cold pressure (often around 1.0 bar), the system needs topping up.
• 2. Refill system: Locate the filling loop or integrated filling valve. Open slowly to allow water into the system while monitoring the gauge. Close the valve when the correct pressure is reached.
• 3. Bleed air: Bleed radiators and the boiler's air vent. Recheck and adjust pressure as needed.
• 4. Inspect for leaks: Look for visible leaks on radiators, valves, and under the furnace. Repair any leaks promptly.
• 5. Pressure sensor check: If pressure is correct but A2 persists, the pressure sensor may be faulty and should be tested and replaced by a technician.