Atlas Copco MD100–400 Air Valve Kit Replacement – 2906030200

The Atlas Copco 2906030200 Air Valve Kit is a service kit used to maintain or overhaul the air valve assembly in MD100–400 dryer systems. The valve controls the required air flow through the dryer during the adsorption and regeneration cycles, while the supplied sealing components help maintain leak-free operation.

Working Process

1. Air enters the dryer from the compressed-air system.
2. Air-valve control directs airflow through the appropriate dryer circuit.
3. Drying cycle allows compressed air to pass through the active desiccant section.
4. Regeneration cycle changes the airflow path so the saturated desiccant can be regenerated.
5. Valve sealing prevents unwanted air leakage between the different flow paths.
6. Valve movement occurs according to the dryer control sequence.
7. Wear and aging can affect the valve, seals and O-rings over time.
8. Service/overhaul replaces worn components using 2906030200.
9. Testing confirms correct valve movement, sealing and airflow after reassembly.

Kit Components

The MD-series parts documentation identifies the following components for 2906 0302 00:

Main Functions

• Controls airflow within the MD dryer.
• Supports adsorption/regeneration cycle switching.
• Provides replacement valve and sealing components.
• Prevents unwanted air leakage.
• Helps maintain correct dryer pressure and airflow.
• Restores reliable valve operation during maintenance.

Typical Failure Symptoms

A worn or faulty air valve may cause:

• Air leakage.
• Incorrect airflow through the dryer.
• Poor regeneration.
• Increased pressure drop.
• Higher pressure dew point.
• Abnormal dryer cycling.
• Reduced drying performance.

Maintenance Procedure

1. Shut down the compressor/dryer according to the applicable Atlas Copco service procedure.
2. Isolate the electrical supply.
3. Fully depressurize the dryer.
4. Allow the equipment to cool.
5. Isolate the relevant air connections.
6. Remove the existing air-valve assembly.
7. Inspect the valve body and mating surfaces.
8. Remove worn seals, gaskets and O-rings.
9. Clean the sealing surfaces.
10. Install the replacement components from 2906030200.
11. Ensure the valve and seals are correctly seated.
12. Reassemble the air-valve assembly.
13. Restore the air connections.
14. Gradually pressurize the dryer.
15. Check for leakage and abnormal pressure drop.
16. Restart the dryer.
17. Verify correct adsorption/regeneration cycling.

Technical Summary

Recommended catalog title:
Atlas Copco 2906030200 – MD100–400 Air Valve Kit, 2906-0302-00.

Important: This is not the cooler kit 2906030300; 2906030200 is the Air Valve Kit, while 2906030300 is the water-cooled regeneration cooler kit.