TM 9-4120-388-14
5-25. PRESSURE REGULATING VALVE - Continued.
(d) Remove button plug from end of pressure regulating valve.
The following must be conducted with the power on. Exercise extreme caution.
(e) Set TEMPerature control thermostat knob fully INCREASE (clockwise)
(f) Start air conditioner in COOL mode and allow suction pressure to stabilize.
(g) To adjust suction pressure, turn adjusting stem clockwise to raise (increase) pressure, or counter-
clockwise to lower (decrease) pressure. If pressure is low (below 56 psi) and cannot be raised by ad-
justment, pressure regulating valve must be replaced. If pressure is high (above 60 psi) and cannot
be lowered by adjustment, test operation of the quench valve (para 5-20) before replacing pressure
regulating valve.
(h) Turn unit OFF.
If pressure regulating valve was properly adjusted:
(i)
Carefully slip junction box into place and align mounting hardware.
(j)
(k) Tighten four captive panel fastener screws in junction box.
Insert bottom flange of lower front panel inside the lip of the cabinet base.
(l)
(m) Push top of lower front panel into position.
(n) Secure lower front panel with two captive panel fastener screws.
(o) Close service valves on unit.
(p) Remove gages or service manifold from service valves.
(q) Install service valve protective caps.
(r) Secure service valve cover with four screws and flat washers.
b. Removal.
(1)
Discharge the refrigeration system in accordance with paragraph 5-7.
(2)
Purge the system with nitrogen and debraze the tube connections. (See para 5-8 and 5-9.)
Remove the pressure regulating valve.
(3)
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