Water Filling, Refilling, and Air Purging Procedures
Filling the System with Water
1. Before filling, open the automatic air vent valve on the circulation pump (this valve is pre-opened at the factory and requires no action by the user) and the air vent valves on terminal devices of the heating system.
2. Introduce softened water at the designated water-filling point in the heating system piping.
3. Observe the water pressure gauge on the gas-fired boiler. Stop filling when the needle reads between 1 bar and 1.5 bar.
4. Start the gas-fired boiler. As the pump runs, if system pressure drops below 1 bar, shut down the boiler.
5. Continue adding softened water until the pressure gauge reads between 1 bar and 1.5 bar.
6. Close the air vent valves on all terminal devices of the heating system.
Note: During initial filling, residual air cannot be fully purged from the system in one go. When the pump operates, trapped air may enter the water pressure detection system, triggering low-water protection or ignition failure, displaying fault codes and related icons. In such cases, simply top up the system pressure to 1–1.5 bar and restart the unit using the power button. Repeat this process several times until stable operation is achieved.
Topping Up Water
1. Shut down the gas-fired boiler and disconnect its power supply.
2. First inspect the heating system for any leaks and confirm the system is fully sealed.
3. Turn the fill/top-up valve handle counterclockwise to open it.
4. Monitor the water pressure gauge on the control panel. Once the needle reads between 1 bar and 1.5 bar, turn the fill/top-up valve handle clockwise to close it.
5. Power on and operate the gas-fired boiler.
Note: During initial filling, residual air may trigger low-water protection or ignition faults. Simply top up the system pressure to 1–1.5 bar and restart the unit. Repeat as needed until normal operation resumes.
Draining the System
a. Draining heating and domestic hot water:
1. Open all valves on the gas-fired boiler and heating system.
2. Open the drain valve located at the lowest point of the heating system; in emergencies, rotate the safety valve to release water.
b. Draining domestic hot water system:
1. Disconnect the gas-fired boiler from the municipal cold water supply;
2. Open the domestic hot water tap(s).