Filling, Refilling & Draining Instructions
Filling
1. Before filling, open the automatic air vent on the circulation pump (already opened before delivery; no user operation is required) and the air vents on the terminal units of the heating system.
2. Add softened water through the reserved filling point in the heating system pipeline.
3. Check the pressure gauge on the gas heating and hot water boiler. Stop filling when the pointer is between 1 bar and 1.5 bar.
4. Start the gas heating and hot water boiler and let the pump run. When the system pressure drops below 1 bar, turn off the boiler.
5. Continue adding softened water until the pressure gauge reads between 1 bar and 1.5 bar.
6. Close the air vents on the terminal units of the heating system.
Note: During the first filling, air inside the system may not be fully discharged at one time. When the pump runs, residual air may enter the water pressure detection system with the water flow, triggering low-water protection, ignition failure, and related fault icons. In this case, simply refill the system to 1–1.5 bar, press the power button to restart, and repeat several times until the system runs stably.
Refilling
1. Turn off the gas heating and hot water boiler and disconnect the power supply.
2. Check the heating system for any water leaks and make sure the system is fully sealed.
3. Turn the filling/refilling valve handle counterclockwise to open the filling/refilling valve.
4. Check the pressure gauge on the control panel. When the pointer is between 1 bar and 1.5 bar, turn the filling/refilling valve handle clockwise to close the valve.
5. Start the gas heating and hot water boiler.
Note: During the first filling, air inside the system may not be fully discharged at one time. When the pump runs, residual air may trigger low-water protection or ignition failure. In this case, simply refill the system to 1–1.5 bar and restart. Repeat several times until normal operation is restored.
Draining
a. Draining the heating/domestic hot water system:
1. Open all valves of the gas heating and hot water boiler and the heating system.
2. Open the drain valve at the lowest point of the heating system. In an emergency, the safety valve may be turned to discharge water.
b. Draining the domestic hot water system:
1. Disconnect the gas heating and hot water boiler from the tap water inlet.
2. Open the domestic hot water tap.