|
| |
ARMY TM 9-4120-381-14
NAVY EE-000-CA-MMA-010/7053-AC
AIR FORCE TO 35E9-136-31
5-21.
PUMP DOWN.
This task covers:
Service
INITIAL SETUP:
Tools:
Tool kit, service, refrigeration unit (Item 1, Appendix B)
Goggles, industrial (Appendix C)
Gloves, chemical (Appendix C)
Personnel: 1
Equipment Condition:
Remove right front condenser panel (para 4-28).
SERVICE
1.
Turn mode switch to OFF.
2.
Remove suction, discharge, head, and hot gas bypass protective caps.
3.
Backseat (counterclockwise) suction and discharge valves (paras 5-33 and 5-34).
WARNING
Death or serious injury may result if personnel fail to observe safety precautions. Use great care to
avoid contact with liquid refrigerant or refrigerant gas being discharged under pressure. Sudden and
irreversible tissue damage can result from freezing. Wear thermal protective gloves and a face
protector or goggles in any situation where skin-eye-contact is possible.
4.
Connect service manifold to compressor suction and discharge valve (para 5-19, steps 3 and 4).
5.
Crack suction valve so gauge will function .(see Figure 5-10).
6. Frontseat (clockwise) head and hot gas bypass service valves (see Figure 5-18).
CAUTION
Never pump the system down below 1 to 2 lbs gauge pressure. A slight positive pressure should always
be left in the system. This prevents air and system damaging moisture from being drawn in thru very
small leaks.
Never pump the system down to a vacuum and then open to atmosphere. A vacuum in the lines, when
opened, would fill the system with air carrying undesirable amounts of moisture into the system.
WARNING
High voltage Is used In operation of this equipment. DEATH ON CONTACT may result if personnel fail to
observe safety precautions.
7.
Connect air conditioner input power at source.
8.
Turn mode switch to COOL mode.
9.
The compressor will operate until the low pressure cutout shuts off the compressor.
10. The compressor will stand idle for a few minutes. During this time, pressure may build up again in the system due to
refrigerant remaining in the crankcase oil. If the pressure builds up, let the compressor run to low pressure cutout.
Allow the compressor to pump down until the pressure no longer builds up.
5-41
|
