TM 10-8145-222-23
MAINTAINER MAINTENANCE
HIGH PRESSURE CUTOUT SWITCH/PRESSURE CONTROL SWITCH
TEST, REPLACE
INITIAL SETUP:
Tools and Special Tools
References
Face Shield (WP 0097, Item 20)
TM 10-8145-222-10
Gloves, Rubber (WP 0097, Item 21)
Refrigeration Equipment
Tool Kit (supplement) (WP 0096, Table 2, Item 7)
Service Refrigeration Ordnance
TM 10-8145-222-23P
Tool Kit (WP 0096, Table 2, Item 6)
Equipment Condition
Personnel Required
Refrigeration unit shut down (TM 10-8145-222-10)
Utilities Equipment Repairer
Top-middle panel removed (WP 0013)
TEST
WARNING
Sudden and irreversible tissue damage can result from freezing. Wear gloves and
face protector or safety glasses in any situation where skin or eye contact with
refrigerant is possible.
Compressor lubricating oil used in this equipment is caustic. Wear gloves and a face
protector or safety glasses in any situation where skin or eye contact is possible. If oil
does contact skin, wash with soap and water.
Dangerous chemical refrigerant under pressure is used in this equipment. Use great
care to avoid contact with liquid refrigerant. Work in a well ventilated area. Heat may
cause the refrigerant to decompose and release irritating, toxic, and corrosive gases.
Prevent contact of refrigerant with flame or hot surfaces.
NOTE
There are two high pressure cutout switches on the compressor, HP1 and HP2. HP1
is green and provides high pressure safety cutout for high head pressure. HP1 has
an upper cutout at 469 10 psi and cuts back in when pressure drops to 350 10
psi. HP2 is red and operates the unloader valve on the compressor head. HP2 has
an upper cutout 348 10 psi and cuts back in when pressure drops to 312 10 psi.
Test the integrity of either high pressure cutout switch, HP1 or HP2, as follows:
1. Remove applicable high pressure cutout switch in accordance with Replace paragraph in this WP.
2. Connect switch to dry nitrogen cylinder (Figure 1, Item 3) using 1/4-inch connection (Figure 1, Item 6).
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