HIGH PRESSURE CUTOUT SWITCH.

TM 5-4120-364-13

Repeat this procedure u n t i l o i l s t a y s c l e a n a n d a c i d f r e e f o r 4 8 h o u r s o f o p e r a t i o n .

4 - 1 9 . HIGH PRESSURE CUTOUT SWITCH.

a. General. T h e high pressure cutout switch (figure 4-12) is located in the

c o m p r e s s o r section. It is preset at the factory to trip at 280 psi, and is wired in-

to the circuit to the thermostat so that operation of all rotors is stopped if dis-

c h a r g e pressure in the refrigerant system reaches that point. The high pressure

switch cannot be repaired and if defective, it must be replaced.

b . A d j u s t . I f the high pressure switch requires

adjustment, it may be ad-

j u s t e d by means of the shaft protruding from the top of

the switch housing. A scale,

l o c a t e d on the front of the switch housing indicates the

pressure at which the switch

i s set to trip. Turn the shaft r i g h t or left to set the

pressure desired as indicated

on the scale.

c. Removal.

( 1 ) Refer to figure 3 - 1 2 and remove the rear panel of the compressor sec-

t i o n by turning fasteners (14) o n e - q u a r t e r turn counterclockwise.

( 2 ) Backseat the compressor discharge service valve and disconnect high

pressure line flare nut at compressor.

( 3 ) Disconnect and tag electrical leads caning from the high pressure

s w i t c h , then remove screws (2, figure 4-12) and high pressure cutout switch (3).

d. Installation.

(1) Mount high p r e s s u r e cutout switch (3) in position on bracket (1) and

secure with screws (2).

(2) Connect electrical leads.

( 3 ) A t t a c h high pressure line with flare nut to compressor but do not

t i g h t e n nut at t h i s time.

( 4 ) O p e n compressor discharge service valve slightly to purge air from

h i g h pressure line, then tighten flare-nut.

( 5 ) Open compressor discharge service valve all the way.

( 6 ) Install rear panel on compressor section by turning fasteners one-

q u a r t e r turn clockwise.

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