Parker Hannifin 903504P ADRP-3 Discharge Bypass Valve 5/8" ODF 0-80 PSI

The Parker Hannifin 903504P is a direct-acting discharge bypass valve designed for refrigeration and air conditioning systems. This adjustable valve provides an economical method of compressor capacity control, automatically bypassing the required amount of discharge gas to the low side to maintain the desired minimum evaporator pressure during periods of low load operation.

Key Features:

• 5/8" ODF (Outside Diameter Flare) solder connections for secure, leak-free installation
• Adjustable pressure range of 0 to 80 PSI for flexible system control
• Direct-acting modulating control valve responds to downstream pressure changes
• Opens automatically when evaporator pressure falls below valve setting
• Remains closed at normal loads, allowing conventional system operation
• Brass body construction with corrosion-resistant stainless steel diaphragm
• External equalizer connection (typically 1/4" ODF) for precise pressure sensing

Applications:

This discharge bypass valve is ideal for refrigeration and air conditioning systems that operate during periods of low load, which can result in coil icing or short cycling. The valve prevents evaporator freeze-up by maintaining minimum evaporator pressure, ensuring reliable system performance and protecting equipment from damage. Compatible with common refrigerants for HVAC and commercial refrigeration applications.