Solenoid Valve (K3 and K4) Coil Removal

TM 5-4120-393-14

4-61. Solenoid Valve (K3 and K4) Coil Removal

This task covers:

a. Testing

b. Repair/Replace

Initial setup.

Tools:

Tool kit, service, refrigeration unit NSN 5180-00-596-1474

Personnel: 1

Material:

Equipment condition:

1. Turn unit power off at power source. If there is a chance that it will be turned on, also disconnect power cable

to air conditioner.

2. Remove junction box number two. See para 4-46.

General Safety Instructions:

WARNING

Disconnect input power to the air conditioner before performing any internal

maintenance. Voltages used can KILL. Shutting the unit off at the control panel

does not disconnect unit power.

NOTE

The following instructions apply to both solenoid valves.

TESTING

Disconnect wiring harness connector from connector on solenoid valve.

Using a continuity tester or a multimeter set on lowest OHMS scale to check for continuity between pins 1 and 2 on

solenoid valve. If continuity is not found, coil is open and must be replaced.

Use continuity tester or multimeter to check for continuity between each pin in connector and the coil casing. If

continuity is found between either pin and the case, coil is grounded and must be replaced.

If continuity checks are satisfactory, apply 24 volts dc from an external power supply across pins 1 and 2 in connector,

and listen for a sharp click when valve changes position. If a click is not heard, internal valve problems are indicated.

Contact Intermediate Direct Support Maintenance for further action.

REPAIR/REPLACE

The repairs are limited to coil replacement only.

Refer all other solenoid repair replacement to Intermediate Direct

Support Maintenance.

4-140