Danfoss 4-Way Reversing valves

The 4-way valves are used in reversible applications such as heat pumps or reversible air conditioning units and chillers.

4-Way Reversing valves Type STF and STF-H

The cycle inversion is initiated by a small solenoid pilot valve, which pilots the movement of a slider, which changes the direction of the refrigerant. The valve is connected to the discharge and suction pipes. The pilot valve ensures a very reliable changeover from cooling to heating mode, the changeover happens instantaneously with a minimum pressure differential. The valve design also guarantees a minimum pressure drop and a very low risk of leakage.

Special safety note for ammable refrigerants! For countries where safety standards are not an indispensable part of the safety system Danfoss recommends the installer gets a third party approval of any system containing flammable refrigerant Please refer to separate drawings of the STF and STF-H valves with special disclaimer regarding usage of flammable refrigerants. Please refer to separate document “Important Notice for usage of STF and STF-H valves with flammable refrigerants (No. S-FD001-3).


Know-How Article