TM 9-4120-408-14
5-26. THERMOEXPANSION VALVE (TEV) MAINTENANCE. (Continued)
Figure 5-22. Thermoexpansion Valve Maintenance.
b. Test and Adjust .
NOTE
Refer to Figure 5-23 for thermoexpansion valve test set up.
(1) Connect bar gauge manifold, hoses, TEV, tees, nitrogen, and other components as depicted in Figure 5-23.
(2) Insert TEV temperature sensing bulb (Figure 5-23, 1) in ice.
(3) Open nitrogen cylinder (70 psi (482 kPa) minimum).
NOTE
Allow nitrogen to bleed off during entire test and adjustment.
(4) Open compound gage hand valve to adjust bleed rate psi or less below TEV outlet pressure.
(5) To Test Valve Seat: Block off bar gauge manifold center port. Pressure should not rise more than 2 psi (14
kPa). Replace defective TEV.
(6) To Check Bulb (1): Remove bulb (1) from ice and warm in hand - pressure should increase. Return bulb (1) to
ice - pressure should drop. Replace defective TEV.
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