BWT heating filling block 51955 DN15, installation horizontally with HT connection DN50 below

AQA therm HFB-1717 BA consists of a heating filling block, a system separator, Druckminderer and shut-off ball valves and is used for the safe and standard-compliant connection of the heating installation to the drinking water supply. The built-in system separator allows the heating installation to be permanently connected to the drinking water installation. This means that the heating system can be easily refilled at any time. System separator function: (AQA therm HFB-1717 BA) According to DIN EN 1717, the system separator is a safety fitting and prevents contaminated water from being pushed back, flowing back or being sucked back into the supply line, into external systems or other system parts. The system separator is divided into three chambers (inlet, middle and back pressure chamber). If no water is drawn off, the system separator is in the idle position under operating pressure. The inlet and outlet non-return valves and the drain valve are closed. When water is drawn off, the system separator is in the flow position. The inlet and outlet non-return valves are open and the drain valve is closed. If the differential pressure between the admission pressure and the medium-pressure chamber falls below 1930 bar, the system separator goes into the disconnected position (return suction). The non-return valve on the inlet side closes and the drain valve opens. Druckminderer function (AQA therm HFB-1717 BA) The Druckminderer reduces the pressure on the input side (inlet pressure) to the desired pressure on the output side (back pressure). The Druckminderer works according to the force comparison principle. The spring force of the control valve counteracts the membrane force the outlet pressure (back pressure) and thus the membrane force, the now greater spring force opens the valve. The outlet pressure increases again until a state of equilibrium between membrane and spring force is reached again. The inlet pressure (primary pressure) has no influence on the control valve in Druckminderer . Pressure fluctuations on the inlet side do not affect the outlet pressure (inlet pressure compensation). According to DIN EN 1717, the AQA therm HFB-1717 BA can be permanently connected to the drinking water line using a hose or pipe (KTW approval required for the hose). After completion of the filling process, the shut-off device must be actuated to prevent uncontrolled refilling of the heating system.