PRIMARY THERMAL EXPANSION VALVE

TM 5-4120-369-14

5-25.

PRIMARY THERMAL EXPANSION VALVE - Continued.

(1) Refer to paragraph 6-3 and discharge the refrigerant system.

(2) Refer to paragraph 4-18 and remove the top covers.

(3) Refer to figure 5-9 . Soften the mastic in the bulb well and remove the expansion

valve bulb. Take care to avoid damaging the capillary tube.

(4) Remove the expansion valve clamp.

(5) Unsolder the expansion valve from the refrigerant system tubing.

Installation.

(1) Refer to figure 5-9 and mount the expansion valve against the compartment wall

using the mounting clamp.

Brazing operations should be carried out using approved

eye protection equipment and rods not containing cadmium.

Certain brazing operations may require mechanical ventilation.

Local preventive medicine personnel should be queried

if doubt exists as to rod composition or ventilation

requirements.

(2) Solder the expansion valve to the refrigerant system tubing.

(3) Refer to paragraph 6-3 and leak test the refrigeration system.

(4) Insert approximately one ounce of thermal mastic (See appendix D) in bulb well.

Insert sensing bulb of expansion valve and move bulb back and forth to distribute mastic.

Position bulb approximate y one inch beyond open end of bulb well.

(5) Refer to paragraph 6-3 and purge the refrigerant system.

(6) Refer to paragraph 4-18 and install top front cover.

Caution should be exercised with fluorocarbon refrigerant

gas (freons) as they can displace oxygen and thereby

cause suffocation.

Personnel with a history or other evidence of cardiac

rhythm abnormalities should be made aware of the

potential for aggravation of existing cardiac rhythm

abnormalities or the induction of arrhythmias, as a

result of exposure to fluorocarbon refrigerant gases

(freons). Such individuals should be evaluated by

local medical authorities before working in environ-

ments where potential freon exposure may occur.

(7) Refer to paragraph 6-3 and charge refrigerant system.

5-26