New perspectives with Danfoss Saginomiya 4 - Way Reversing Valves
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Danfoss Saginomiya 4 - Way Reversing Valves STF 4-way reversing valves • Wide application range - complete capacity range - available for all common refrigerants (R407C, R410A, R404A, R134a, R22) - many different connection diameters and configurations • High reliability - unique design - instantaneous changeover at minimum pressure differential - mechanism to prevent incomplete changeover - minimized leakage • CE approved

The 4 way valves are used in reversible applications such as heat pumps or reversible air conditioning units and chillers. The 4 way valve allows an inversion of the refrigeration cycle, changing from cooling mode in summer to heating mode in winter. 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. (2) condition 2: 54,4 °C condensing / 7,2°C evaporating / 5°C super-heat / 5°C sub-cooling (3) see valve style overview on page 7 (6)...

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. The STF models offer a wide range of connection dimensions, configurations and capacity for specific applications. The standard STF models are packed as 1 pc. per box providing increased flexibility. Standard coils are water-proof (IP65)

Capacity* for 4-way reversing valves type STF-G A AB Suction pressure drop [bar] * based on: Condesing Temp = 54,4 °C, Evaporating Temp = 7,2 °C Superheat Temp = 5 K, Supercool Temp = 5 K Capacity* for 4-way reversing valves type STF-G A A B Suction pressure drop [bar] * based on: Condesing Temp = 54,4 °C, Evaporating Temp = 7,2 °C Superheat Temp = 5 K, Supercool Temp = 5 K

Capacity* for 4-way reversing valves type STF-G A AB Suction pressure drop [bar] * based on: Condesing Temp = 54,4 °C, Evaporating Temp = 7,2 °C Superheat Temp = 5 K, Supercool Temp = 5 K Capacity* for 4-way reversing valves type STF-G A AB Suction pressure drop [bar] * based on: Condesing Temp = 54,4 °C, Evaporating Temp = 7,2 °C Superheat Temp = 5 K, Supercool Temp = 5 K

P rinciples Construction and operation in cooling and heating cycle 1. discharge connection 2. connection to evaporator/ condenser 3. suction connection 4. connection to condenser/ evaporator 5. valve body 6. slider 1 The valve is composed of three basic components: - pilot valve - main valve body, including valve slider - solenoid coil The 4-way valve slider is shifted by changes in differential pressure in the valve which is actuated by the pilot solenoid valve. The valve slider is specially designed to prevent incomplete changeover and movement with minimum pressure differential. 3...

* STF-2501G does not have a bracket Coils codification Example: STF 01A J 504 F _1_ I valve type II coil size III electrical rating IV coil body serial number V lead wire / terminal style serial number VI screw for coil

For optimum performance of 4 - way reversing valves, observe the following recommendations and guidelines: 1. The following installation is possible for 4-way reversing valve: a. in horizontal position, the orientation of STF series 25, 30, 40, 50 and 60 series should be in the range from 0o to 180o,. For the remaining valve types any orientation from 0o to 360o is possible (Fig.1 ). in vertical position, the valves can be installed in any orientation as long as the coil stem position is up (Fig. 2a). 2. Before installing, thoroughly clean the inner part of pipes to prevent dust or dirt...