
Mechanical pressure regulating valves
Mechanical pressure regulating valves help control key system pressures in cold rooms and other refrigeration applications.
In cold room systems, they are used to support stable evaporating conditions, protect compressors during demanding operating periods, and help maintain the right condensing and receiver pressure where needed.
The range covers several pressure-regulating functions across refrigeration and air conditioning systems, including evaporator pressure regulation, crankcase pressure regulation, condensing and receiver pressure regulation, and compressor discharge pressure control.
Mechanical pressure regulating valves are also used in refrigeration and air conditioning systems more broadly, including systems with air-cooled condensers, water chillers, heat-recovery applications, and selected industrial refrigeration duties
Features and benefits
- Supports stable pressure control across refrigeration systems
- Helps maintain constant evaporating pressure and evaporator surface temperature where required
- Helps protect the compressor motor against overload during start-up, after long standstill periods, or after defrost
- Supports constant and adequately high condensing and receiver pressure in systems with air-cooled condensers and heat-recovery applications
- Application-focused design for systems operating under large load variations
- Accurate, adjustable pressure regulation
- Low pressure drop under normal load conditions
- Reliable operation with high tightness in closed position
- Hermetic valve designs that help reduce external leakage risk
- Wide capacity and operating ranges
Product types shown: 7

KDC / GVD
The KDC/GVD valve is a pressure control valve. The valve controls the discharge pressure of the compressor to ensure fast build-up of pressure and lubrication pressure. The valve also acts as a check valve in the discharge line of the compressor.
The KDC/GVD valve is force-controlled so that when pressure in the oil separator becomes 2 bar (29 psi) higher than the suction pressure, the spring is compressed, and the valve opens. In low-pressure units (boosters), the spring requires a differential pressure of 0.5 bar (7 psi) for the valve to open.
KVD
KVD is a modulating receiver pressure regulator. It opens on falling receiver pressure and bypasses hot gas to maintain the receiver pressure at the regulator setting (adjustable).
KVD and KVR form a regulating system, used to maintain constant and adequately high condensing and receiver pressure in plant with heat–recovery, and in refrigeration and air conditioning plant with air - cooled condensers.
KVP
The KVP is mounted in the suction line after the evaporator and is used to:
1. Maintain a constant evaporating pressure and thereby a constant surface temperature on the evaporator. The regulation is modulating. By throttling in the suction line, the amount of refrigerant gas is matched to the evaporator load.
2. Protect against an evaporating pressure that is too low (e.g. as protection against freezing in a water chiller). The regulator closes when the pressure in the evaporator falls below the set value.
3. Differentiate between the evaporating pressures in two or more evaporators in systems with one compressor.
OFV / OFV SS
OFV are angle-way pressure regulating valves, which have adjustable opening pressure and cover the deferential pressure range (ΔP): 2 – 8 bar (29 – 116 psi). The valve can be closed manually, e.g. during plant service and have backseating, enabling the spindle seal to be replaced with the valve still under pressure.
The valves are especially designed to prevent fluttering due to low velocity and/or low density. In consequence it is possible to apply the valves with wide fluctuations in capacity demands, i.e. from maximum performance to part load. A flexible O-ring provides perfect sealing over the seat.

