Compressor exchange with no Ex zone

Example task: Exchange the semi-hermetic compressor operated with A2L refrigerant R454C. The compressor is located on a rack in a machine room. The room has some ventilation. There is no leak from the system.

Special tools or preconditions:

• Mobile A2L gas detector
• A2L leak detector
• A2L fire extinguisher
• A2L recovery equipment
• Vacuum pump with external switch, outside room
• Extra fan
• A2L anti-sparking tool – not necessary
• Avoid Ex zone! Avoid / check for leakage!

Working steps or preconditions:

1. Educated worker
2. Read / inform for risk assessment of system
3. Have A2L fire extinguisher ready
4. Put warning sign to notify work in progress, especially where refrigerant might be released
5. Power off compressor / system
6. Ventilation on
7. a. Install extra fan
7. Go in with gas detector / check regularly with gas detector or machinery room detector
8. Close compressor shut off valves
9. Release pressure
10. a. Small gaseous amount to marked outside area
10. Oil heater on
11. Evacuate compressor
12. a. Release vacuum pump outlet to marked outside area
12. Charge compressor with Nitrogen
13. Remove compressor
14. a. Leave valves on pipes
15. b. Check valves for tightness with leak detector
16. c. Close compressor connections pressure tight with flanges or valves
17. d. Evacuate removed compressor
18. e. Put nitrogen holding charge in removed compressor
14. Put sticker for flammable gas on return compressor
15. Install replacement compressor
16. Evacuate replacement compressor
17. Open compressor shut off valves
18. Remove warning signs
19. Take compressor into operation again