TM 9-4120-370-14
TO 35 E9-229-1
5-23. EVAPORATOR COIL - Continued.
(3) Wtlllepurging thesystem with nitrogen braze thetube joints. (See para5-8and para5-9,)
(4) Replace thedehydrator. (Seepara 5-14.)
(5) Leak test all newly connected joints and those in the repair area. (See para 5-10)
(6) Install grommets on inlet and outlet tubes.
(7) Reinstall and tape in place tubing insulation that was removed from suction line tubing. If it was damaged,
replace with tubing insulation, item 17, Appendix E,
(8) Secure upper heater support with four rivets,
(9) Secure heater thermostat and bracket with two rivets.
(10) Install heaters (HR1 through HR6). Check that all wire Ieadsareconnected and tags removed prior to instal-
lation of top panel. (See para 4-62.)
(11) Evacuate and charge the refrigeration system. (See para 5-11 and para 5-12.)
Install conditioned air filter. (See para 4-32.)
Follow-on procedure:
AdjustnlenttTest
a.
(1) Valves are factory set to start opening when suction pressure decreases to 58 psig. Do not adjust unless
you are sure adjustment is necessary.
(2) Perform a refrigeration pressure check on unit in accordance with paragraph 5-13. Leave the gages or
service manifold attached.
(3) Set Temperature control thermostat knob fully INCREASE (clockwise), start air conditioner in COOL
mode, and observe pressure gages. Suction pressure should drop to 58 2 psi(4. O 0.14 kg/cm2) shortl.
after compressor starts, and then remain constant.
(4) To adjust suction pressure, remove button plug from top of pressure regulator valve and turn adjusting stem
clockwise to raise (increase) pressure, or counterclockwise to lower (decrease) pressure, If pressure is
low (below 56 psi) and cannot be raised by adjustment, pressure regulator valve must be replaced, If pres-
sure is high (above 60 psi) and cannot be lowered by adjustment, test operation of the quench valve (para
Removal
b.
(1) Discharge the refrigerant system per paragraph 5-7.
(2) Remove the lower front panel. (See para 4-25.)
(3)
Using screwdriver and wrench, remove screw, flat washer, nut, spacer, and clamp from pressure regulator
valve.
(4) Carefully cut tiedown strap that holds quench valve capillary tubing coil to pressure regulator valve. Pull
capillary coil away from pressure regulator valve.
