A frost protection valve with integrated vacuum breaker is installed in the flow and return lines of the system. The valve must be installed as close as possible to the outdoor unit of the heat pump so that sensitive components of the heat pump are protected from damage caused by freezing of the heating circuit water. If maintenance is required, the thermostatic cartridge can be replaced, checked and reinstalled without draining the heating circuit water thanks to the integrated mounting valve.
If the temperature of the medium in the heating system drops to 3 °C, the thermostatic element inside the valve opens so the medium can flow to the outside. The resulting negative pressure opens the vacuum breaker and supports the draining of components such as the heat exchanger, pipes, pumps or valves. If the temperature of the medium rises above 4 °C, the thermostatic element automatically shuts off the flow of the medium from the system.