TM 10-8145-222-23
0014
SERVICE CONTINUED
Evacuation and Dehydration
Perform an evacuation and dehydration of the refrigerant system as follows:
CAUTION
Moisture in the refrigeration system can cause copper plating, acid sludge formation,
freeze-up, and formation of acids that result in metal corrosion. It is very important to
make sure that no moisture is in the refrigerant system before it is charged.
1. Perform a pressure leak check.
NOTE
Ambient temperatures below 60F may cause the formation of ice before moisture
removal is completed. It may be necessary to use heat lamps, or other alternate
source of heat, to raise and keep temperature above 60F.
2. Keep ambient air temperature above 60F to speed up evaporation of moisture and prevent system damage.
CAUTION
Refrigerant is damaging to the earth ozone layer. Always use a refrigerant reclaimer
when removing refrigerant from a system.
3. Connect refrigerant reclaimer, if not already connected, using four evacuation hoses.
4. Remove refrigerant using an approved refrigerant reclaimer.
CAUTION
Standard service hoses are not suitable for evacuation procedures. Do not use
standard service hoses as damage to the system may occur. Use only evacuation
hoses when performing evacuation and dehydration procedures.
5. Connect one evacuation hose between vacuum pump manifold and compressor discharge service valve.
6. Connect second evacuation hose between vacuum pump manifold and compressor suction service valve.
7. Connect third evacuation hose between vacuum pump manifold and receiver outlet valve.
8. Connect one evacuation hose between vacuum pump and vacuum gauge manifold.
9. Connect one evacuation hose between vacuum gauge and vacuum gauge manifold.
10. Close compressor suction service valve (Figure 1, Item 1) by turning counterclockwise.
0014-12
