REFRIGERATION SYSTEM. - TM-5-4120-369-140089

TM 5-4120-369-14

( 1 ) By Electronic Leak Detector.

Using a G.E. Type H-2 Leak Detector, or equivalent, proceed as follows:

(a) Turn on and calibrate the leak detector as described in the instructions supplied with the instrument.

(b) S1OWly pass the detector probe tip over the sweat fittings, mechanical couplings and valves in the

refrigerant circuit. If refrigerant is leaking, detector will provide a visible or audible signal.

(2) By Halide Leak Test. Using a propane flame halide leak detector, proceed as follows:

(a) Slowly pass the exploring tube on the torch over the sweat fittings, mechanical couplings and valves. If

refrigerant is leaking, the flame will be affected as follows:

Small leak -- flame changes from blue to green

Large leak -- flame changes from blue to dense blue with reddish tip

Massive leak -- may extinguish flame

(b) Use the soap-bubble method to localize the leak to a defective component or connection.

(3) By Soap Solution Method. Using either a prepared bubble-type leak detector compound or a solution of

hand soap in water, proceed as follows:

(a) Apply the solution to all points of possible leakage, and watch for bubble formation indicating a

refrigerant leak.

NOTE

Allow solution to remain on joints long enough for small leaks to

form noticeable bubbles.

(b) Wipe solution from joints and mark spots where leakage is observed,

REFRIGERATION SYSTEM.

Opening System. When the refrigeration system must undergo maintenance that requires the system to be

opened for removal of parts, the system must first be discharged with a Recovery/Recycling Unit (paragraph 6-3). After the

repair has been made and all soldering completed, the system must be tested for leaks and charged (paragraph 6-3),

Removal of Parts. When the refrigeration system must undergo maintenance that requires the refrigerant system

to be opened for removal of parts, the system must first be discharged with a Recovery/Recycling Unit and purged (figure 6-1).

After the repair has been made and all soldering completed, the system must be tested for leaks and charged (paragraph 6-3).

Except for flare nut connection, all the tubing attachments in the refrigerant ion system are "sweat joints" which are opened by

heating with a brazing torch. During unseating, shield the wiring, insulation, painted metal, and valves from the heat of the

torch. Use wet cloths to protect the gas charge in expansion valve bulbs and capillary tubing.

NOTE

Replace dehydrator each time refrigerant system is opened.

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