The product innovation for reliable winter operation of heat pumps is installed in the immediate vicinity of the outdoor unit in the system flow and return. The decisive benefit: At low winter temperatures, sensitive system components are protected in a simple, yet highly effective way. If the heat exchanger freezes, environmentally harmful or explosive refrigerant (R290) can escape and cause hazards. It is therefore important to effectively prevent such damage.

Reliable protection

The frost protection valves AAV 102 / 302 protect against this risk and ensure reliable operation during the winter, based on opening and closing temperatures: When the temperature of the medium drops to 3 °C, the thermostatic element inside the valve opens and allows the heating circuit water to drain to the outside. The resulting negative pressure opens the vacuum breaker and supports the draining of components of the outdoor unit. If the temperature of the medium rises above 4 °C, the thermostatic element automatically shuts off the flow of the medium from the system. Prior to recommissioning, the system is refilled and de-aerated and the system pressure is checked.

The frost protection valves AAV are available for system connections G1 and G1¼.