TM 9-4120-411-14
5.10 REFRIGERANT SYSTEM PRESSURE CHECK - CONTINUED.
Table 5-2. Nominal Operating Pressure At Suction And Discharge Service Valves
COOLING MODE
Coil Entering Air Temperature
Pressure At Service Valve
Inside
Outside
Suction
Discharge
85 F (29 C)
35 psi (242 kPa)
200 psi (1380 kPa)
80 F (27C)
125 F (52 C)
42 psi (290 kPa)
345 psi (2381 kPa)
Coil Entering Air Temperature
Pressure At Service Valve
Inside
Outside
Suction
Discharge
17 F (-8 C)
7 psi (48 kPa)
150 psi (1035 kPa)
70 F (21C)
47 F (8 C)
20 psi (138 kPa)
170 psi (1173 kPa)
5.11 TUBING AND FITTINGS TESTING, REPAIR AND REPLACEMENT.
THIS TASK COVERS:
a. Testing
b. Removal
c. Installation
INITIAL SETUP:
Tools
Materials/Parts
Refrigeration Unit Service Tool Kit
Insulation Tape
WARNING
Rotating parts and lethal voltage levels are used in operating the FDECU. Be sure
power source is disconnected. Injury or death can occur if connected to power
source.
(1) Shutdown the FDECU per paragraph 2.4 and disconnect it from power source.
WARNING
The FDECU cover is heavy. Be sure the cover retaining rod is in place and
properly secured with hair pin cotter. Injury can occur if cover drops.
(2) Raise and secure cover to access tubing and fittings inside unit.
(3) Remove panels as necessary to access tubing and fittings.
(4) Remove insulation as necessary.
(5) Leak test the tubing and fittings per paragraph 5.7. If a leak is found, skip steps (6) thru (8) and repair or
replace the tubing or fitting as necessary.
(6) Install insulation if removed and secure with insulation tape as necessary.
(7) Install any panels removed to access tubing and fittings.
(8) Close and secure cover.
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