Visually inspect the sight-glass liquid indicatcr for physical damage, cracked or broken sight-glass or similar defects.
Before removing the sight-glass
liquid indicator from the refrigeration system. the system must be completely
discharged. Proceed-as follows:
a. Remove five screws from the fresh air screen, and remove the screen.
to figure 5-8 for indenification
of service valves. Discharge the system
in accordance with paragraph
c. While waiting for the system to discharge, remove panels and grilles as follows:
(1) Remove 18 screws and washers from the four sides of the fabric cover, and remove the fabric cover.
(2) Remove 15 screws and packing washers from the top panel, and five screws from the
rear flange. Remove the top panel.
(3) Remove the air intake grille by turning six can-lock studs clockwise. Remove the air filter by removing
two screws from the retainer and pulling out the filter.
(4) Unscrew two panel fastener screws in the upper edge of the lower panel, and remove the panel.
d. Remove the control panel assembly and the junction box
in accordance with paragraph 5.53.
e. Remove the four screws from the ends of the pressure cutout switch housing, and move the housing aside to
permit access to the sight-glass liquid indicator.
Remove the sight-glass liquid indicator from the air conditioner as follows:
All refrigerant gas must be discharged from the system, and a flow of dry nitrogen connected to the
discharge service valve before removing the sight-glass.
a. Remove two screws and lockwashers from the sides
of the bracket, and remove the bracket and spacer from
inside the air conditioner.
b. With dry nitrogen flowing through the system,
sight-glass liquid indicator, and remove
the indicator from inside the air conditioner.
Install the sight-glass liquid indicator as directed in the following procedure.
a. Connect tubing to sight-glass, and place spacer between sight-glass and casing.
b. Place bracket over back of sight-glass assembly, and secure through the casing with two screws and
c. With dry nitrogen flowing through the system
at 1-2 cfm (0.1 -0.2
M3/min), braze tubing joints to
sight-glass liquid indicator.