TM 10-8145-222-23
0019
REPLACE
Replace either high pressure cutout switch, HP1 and HP2, as follows:
WARNING
Approved hearing protection must be worn when operating the MTRCS diesel
engine. Failure to observe this precaution may result in severe and permanent
hearing loss.
NOTE
There are two high pressure cutout switches attached to the compressor. One of the
switches is green in color (HP1) and is installed close to the compressor. The second
high pressure cutout switch is red in color (HP2) and is installed adjacent to HP1.
HP2 is utilized as a high pressure cycling switch when the refrigeration unit is being
operated in heat mode.
In order to ease removal of HP1, removal of HP2 is required first. This task will
provide you with instructions for removing and replacing both HP1 and HP2
simultaneously.
1. Pump refrigeration unit down (WP 0014, Service).
2. Disconnect battery negative (-) terminal (WP 0053, Disconnect).
NOTE
The compressor must be isolated in order to replace high pressure cutout switch.
This can be accomplished by frontseating (closing) both compressor service valves.
3. Frontseat (close) compressor suction service valve (Figure 2, Item 7) by turning clockwise until it stops.
4. Frontseat (close) compressor discharge service valve (Figure 2 Item 8) by turning clockwise until it stops.
5. Slowly release compressor pressure through service valve gauge ports.
6. Disconnect electrical connector (Figure 2, Item 1) from high pressure cutout switch 2 (HP2) (Figure 2, Item 2).
7. Disconnect electrical connector (Figure 2, Item 5) from high pressure cutout switch 1 (HP1) (Figure 2, Item 6).
8. Remove HP2 (Figure 2, Item 2) from elbow (Figure 2, Item 3).
9. Remove HP1 (Figure 2, Item 6) from tee (Figure 2, Item 4).
0019-3
