Pulse Width Expansion Valve

The Sporlan SPW line of electric expansion valves uses pulse width modulation (PWM) control to manage refrigerant flow in direct expansion CO2, HFC, HCFC and HFO (nonflammable & nontoxic) refrigeration systems. The valve’s duty cycle is varied based on measured evaporator superheat. Typical controllers monitor superheat and vary the duty cycle across a 6 second period.

Sporlan’s Pulse Width Modulation Valves are rated at 100% duty cycle, no reserve capacity. Pulse Width Modulation Valves are typically sized between 50% and 85% duty cycle. This allows additional capacity for pulldown at start-up and after defrost. Further consideration should be given to the liquid line size to avoid excessive liquid hammer. Liquid line velocity should not exceed 3 ft/second.

The SPW valve family offers 8 port sizes to cover a wide range of
evaporator loads. The serviceable port and strainer design allows the contractor to service and clean the SPW valve or easily replace the port during a refrigerant retrofit.

The SPW Valve line is rated for a Maximum Rated Pressure (MRP) of 1305 psig (90 barg). The Maximum Operating Pressure Differential (MOPD) is 507 psid (35 bar). Solenoid coils are available for 24 VAC/60 Hz, 110-120 VAC / 50-60 Hz and 220-240 VAC / 50-60 Hz.