Atlas Copco Oil Stop Valve Kit Replacement – 2906096100

Atlas Copco 2906096100 – CV/OSV C190 Kit

The Atlas Copco 2906096100 (2906-0961-00) CV/OSV C190 Kit is a service and maintenance kit used in compatible Atlas Copco oil-injected rotary screw compressor systems. The assembly combines a Check Valve (CV) and Oil Stop Valve (OSV) to control oil flow, maintain the correct flow direction, and prevent unwanted oil migration during compressor unloading and shutdown.

Working Process:

During normal compressor operation, the screw air-end requires a controlled supply of compressor oil for lubrication, cooling, sealing, and efficient compression. The oil circulates through the compressor oil circuit under pressure.

The Oil Stop Valve (OSV) regulates the oil passage to the compressor air-end. When the compressor is running, the pressure generated within the oil circuit acts on the valve mechanism and moves it into the operating position. This permits the required quantity of oil to circulate toward the air-end.

The circulating oil lubricates the rotating screw components, removes heat generated during compression, and assists in sealing the internal clearances between the screw rotors.

The Check Valve (CV) provides one-way flow control. It allows flow in the intended direction while preventing reverse flow when the pressure differential changes.

During loaded operation, both valve functions work together to maintain the intended oil-flow path and prevent unwanted reverse movement of oil through the compressor circuit.

When the compressor unloads or stops, the operating pressure in the oil circuit decreases. The spring-assisted Oil Stop Valve moves toward its closed position.

The OSV restricts the oil passage and helps prevent excessive oil from draining or migrating into the air-end while the compressor is stopped.

At the same time, the Check Valve prevents unwanted reverse flow. This helps maintain the correct pressure and oil-flow conditions during unloading and shutdown.

This shutdown function is important because uncontrolled oil migration can cause excessive oil accumulation in the air-end, difficult starting, increased oil consumption, oil carryover, or abnormal compressor operation.

Parts references identify 2906096100 / 2906-0961-00 as a CV/OSV kit and specifically describe it as “CV/OSV C190.” One application reference lists it for GA90/160 C190, while another lists compatibility with GA160, GA132, GA110, GA90 and C190. Exact compatibility should therefore be confirmed against the compressor serial number before installation.

The Oil Stop Valve performs the oil-shutoff function, while the Check Valve provides non-return flow protection. Springs provide the required return and closing force, while the sealing components maintain leak-resistant connections.

During continuous operation, the CV/OSV assembly is exposed to hot compressor oil, pressure fluctuations, vibration, temperature changes, and repeated loading/unloading cycles.

Over time, valve components can become worn or contaminated. Springs may lose their required force, while sealing components can harden, deform, or deteriorate.

A defective Oil Stop Valve may fail to close correctly after shutdown. This can allow oil to migrate into the air-end and may result in excessive oil accumulation, increased oil consumption, oil carryover, difficult starting, or abnormal compressor operation.

A defective Check Valve may allow reverse oil flow through the circuit. This can disturb the intended flow direction and cause unwanted oil or pressure migration.

If the valve assembly becomes restricted or fails to open correctly during operation, the oil supply to the air-end may be reduced. Insufficient oil circulation can negatively affect lubrication, cooling, and sealing of the compressor element.

Maintenance Procedure:

Before servicing the CV/OSV assembly, the compressor must be stopped, electrically isolated, completely depressurized, and allowed to cool.

The existing valve assembly should be removed according to the applicable Atlas Copco service procedure. The Oil Stop Valve, Check Valve, springs, sealing components, valve seats, and oil passages should be inspected for wear, contamination, corrosion, deformation, and leakage.

Worn components should be replaced using the 2906096100 CV/OSV C190 Kit.

All sealing components must be installed carefully without twisting, cutting, or damaging the sealing surfaces. The Oil Stop Valve, Check Valve, springs, and other components must be installed in their correct positions and orientations.

After reassembly, the compressor should be checked for oil and air leakage.

The compressor should then be operated through its start-up, loaded, unloaded, and shutdown cycles.

During testing, the Oil Stop Valve should permit the required oil circulation during normal operation and close effectively when the compressor unloads or stops. The Check Valve should prevent unwanted reverse flow.

Correct operation of the CV/OSV assembly maintains proper oil circulation during compressor operation while reducing oil migration and reverse flow during unloading and shutdown.

Using the Atlas Copco 2906096100 CV/OSV C190 Kit during scheduled maintenance helps restore oil-flow control, reverse-flow protection, reliable sealing, proper shutdown behavior, and dependable compressor performance.

Part Number: 2906096100
Alternative Number: 2906-0961-00 / 2906 0961 00
Brand: Atlas Copco
Part Description: CV/OSV Kit
Designation: CV/OSV C190
Component Type: Check Valve + Oil Stop Valve service kit
Known Applications: Atlas Copco GA90, GA110, GA132, GA160 and C190 references
Primary Function: Controls oil flow and prevents unwanted reverse flow
Operating Function: Allows controlled oil circulation during operation and restricts oil migration during unloading/shutdown
Main Benefits: Proper lubrication, reduced oil migration, reverse-flow protection, reliable sealing, improved shutdown performance, and dependable compressor operation.

Disclaimer: All manufacturer names, trademarks, model numbers, and part numbers are used solely for identification and compatibility purposes. Our products are high-quality aftermarket replacement products and are not manufactured, sponsored, endorsed, or authorized by the original equipment manufacturer (OEM). All trademarks remain the property of their respective owners.