TM 10-5410-228-24
ENVIRONMENTAL CONTROL UNIT (ECU).
R22 Refrigerant System Servicing.
This task covers:
a. Manifold Gage Set Installation
e. Checking for Leaks
b. Recovering Refrigerant
f. Charging System
c. Adding Compressor Oil
g. Pump Down System
d. Evacuating System
h. Manifold Gage Set Removal
INITIAL SETUP
Tools/Test Equipment:
Equipment Conditions:
Shop Equipment, Automotive Maintenance and
Power shut off, power panel and rear control panel
Repair (Item 38, Appendix B)
tagged.
Tool Kit, Service: R22 Refrigeration Unit
ECU work platform installed (reference
(Item 52, Appendix B)
TM 10-5410-228-10).
Gloves (Item 16, Appendix B)
ECU covers and doors opened or removed as
Goggles (Item 17, Appendix B)
required (see para 2.14.1).
Two Manifold Gage Sets (Item 26, Appendix B)
References:
Vacuum Pump (Item 31, Appendix B)
TM 9-2320-387-10
R22 Refrigerant Recovery and Recycle Unit
TM 9-2320-387-24-1
(Item 33, Appendix B)
TM 10-5410-228-10
R22 Refrigerant Cylinder (Item 32, Appendix B)
Gage Set Tee (Item 14, Appendix B)
Materials/Parts:
Refrigerant Gas Leak Detector (Item 3,
Lubricating Oil (Item 32, Appendix C)
Nitrogen (Item 34, Appendix C)
R22 Refrigerant (Item 40, Appendix C)
The R22 refrigerant system is pressurized. To prevent injury to personnel, gloves and eye
protection must be worn when working on R22 refrigerant system.
Prevent contact of R22 refrigerant with flame or hot surface. Heat causes R22 refrigerant to
break down and form carbonyl chloride (phosgene), a highly toxic and corrosive gas.
R22 refrigerant must be recovered. Venting R22 refrigerant into the atmosphere is a
violation of public law and subject to severe penalties.
Do not attempt to remove or connect refrigerant servicing equipment while ECV is running.
Failure to observe these warnings can result in injury to personnel.
Do not run unit or compressor while servicing.
NOTE
This procedure for servicing the refrigeration system uses two manifold gage sets. Servicing
may be accomplished using only one manifold gage set, but the time to accomplish the task
will be longer.
Whenever any refrigerant component is replaced, the system must be recovered, evacuated
and a new filter/drier installed (per para 3.9.13).
a. Manifold Gage Set Installation (Refer to Figure 3-6)
(1)
Hang manifold gage sets (1) at convenient location on passenger side of ECU next to service
ports (2) and turn both the high pressure gage valves (3) and the low pressure gage valves (4)
on gage sets (1) clockwise to their closed (front seated) position.
