Atlas Copco ZT55–90 Cooler Service Kit Replacement – 2906066300

The Atlas Copco 2906066300 is a Cooler Service Kit used for maintaining the cooling system of applicable ZT55–90 oil-free compressors. It contains replacement O-rings and sealing washers used to restore the sealing integrity of the cooler connections during servicing. Atlas Copco’s official listing gives the kit weight as 222 g.

Working Process

1. Compression – Air is compressed inside the oil-free compressor elements, generating heat.
2. Hot Air Flow – Heated compressed air moves through the compressor’s cooling stages.
3. Heat Transfer – The cooler transfers heat away from the compressed-air/cooling circuit.
4. Cooling – Cooling air or the applicable cooling medium removes the generated heat.
5. Temperature Control – The cooler maintains the air and compressor components within their required operating temperature range.
6. Sealing – O-rings and seal washers prevent air or cooling-medium leakage at cooler connections.
7. Continuous Operation – The cooling circuit operates continuously while the compressor is running.

Kit Components

Atlas Copco’s official listing specifies:

Main Functions

• Maintains cooler sealing.
• Prevents leakage from cooler connections.
• Supports effective heat transfer and cooling.
• Replaces aged or damaged O-rings.
• Restores sealing during cooler maintenance.
• Helps maintain reliable ZT compressor operation.
• Reduces the risk of unplanned cooling-system leakage.

Possible Failure Symptoms

Worn cooler seals can contribute to:

• Air or coolant leakage.
• Reduced cooling performance.
• High compressor temperature.
• Temperature alarms.
• Increased operating stress.
• Compressor shutdown.
• Reduced overall compressor efficiency.

Maintenance Procedure

1. Shut down the compressor according to the applicable Atlas Copco service procedure.
2. Isolate the electrical supply.
3. Fully depressurize the compressor.
4. Allow the cooling system to cool.
5. Isolate the relevant cooling/air circuit.
6. Open the cooler service area.
7. Remove the old O-rings and sealing washers.
8. Inspect the cooler connection surfaces.
9. Clean the sealing surfaces.
10. Install the replacement components supplied with 2906066300.
11. Ensure each O-ring is correctly seated and free from twisting or damage.
12. Install the M32 seal washers correctly.
13. Reassemble the cooler connections.
14. Restore the cooling and air circuits.
15. Restart the compressor.
16. Check carefully for leakage.
17. Monitor operating temperature and verify normal cooling performance.

Technical Summary

Recommended catalog title:
Atlas Copco 2906066300 – ZT55–90 Cooler Service Kit for Oil-Free Compressors, 2906-0663-00.

Atlas Copco’s official catalog confirms 2906066300 as the Cooler Service Kit for ZR/ZT Oil-Free Compressors, with ZT55 specifically identified in the product information and the listed O-ring/seal components.

Important: Do not confuse 2906066300 with 2906067300; parts references identify 2906066300 as the ZT55–90 cooler service kit, while 2906067300 is the ZR55–90 cooler service kit.