TM 9-4120-378-14
5.28 TUBING AND FITTINGS-TEST/REPLACE. This task covers test, removal and installation.
INITIAL SETUP
Materials/Parts:
Equipment Conditions:
Nitrogen (Appendix E, Item 4)
Top covers removed (paragraph 4.17)
Brazing solder (Appendix E, Items 5 and 6)
Refrigerant system discharged (paragraph 5.4)
Brazing flux (Appendix E, Item 7)
Refrigerant-22 (Appendix E, Item 10)
Test Equipment:
Halogen test detector and leak standard
Remarks
Action
Location/Item
Disconnect air conditioner power sup-
ply before doing maintenance work on
the electrical system.
Avoid bodily contact with liquid refrig-
erant and avoid inhaling refrigerant
gas. Be especially careful that refrig-
erant does not come in contact with
eyes. In case of refrigerant leaks, ven-
tilate area immediately.
Check all piping and connections with a General
Test
a . Electric Type H-2 halogen test detector (or ap-
proved equal).
b . Calibrate the detector with a General Electric LS-20
leak standard (or approved equal) for a pure refrig-
erant leak rate of 0.1 ounce (2.8349 gins) per year.
c.
Replace any piping or connection that is leaking be-
yond the rate of 0.1 ounce (2.8349 gins) per year.
a.
Debraze and remove tubing only when necessary
Removal
to remove a defective part.
b.
See paragraph 5.6.
When brazing, constantly purge the refrigerant sys-
tem with dry nitrogen to prevent scale formation
within the refrigerant system.
