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Service Specifications

AMBIENT TEMPERATURE-PRESSURE

Ambient Temperature High Side Pressure (PSI)
60 95-115
65 105-125
70 115-135
75 130-150
80 150-170
85 165-185
90 175-195
95 185-205
100 210-230
105 230-250
110 250-270
115 265-285
120 280-310
NOTE: All temperatures given in Fahrenheit.
REFRIGERATION PRESSURES

Application PSI
Low Side Gauge
  Ford Motor Co. (1)
    1971-72 W/Thermostatic Switch 10-20
1971-72 W/STV 4-25
1973 W/Thermostatic Switch 15-25
1973 W/STV 4-25
1974-76 W/STV 10-20
1977-78 W/STV 5-20
  General Motors
    STV Valve 29-31
POA Valve 28-31
  Chrysler Corp.
    ETR Valve 22-30
EPR Valve 22-31
EPR II Valve 22-29
  All Others W/Thermostatic Control 15-30
    Compressor Cut-Out Point 12-15
Compressor Cut-In Point 36-39
High Side Gauge (2) 185-205
(1) This is the reading taken at the normal low side service valve. STV service port connection is for an auxiliary gauge to read evaporator pressure. Proper pressure is 27.5-29.5 psi (at sea level). Note that this gauge reading is susceptible to changes in altitude (at a rate of.5 psi gauge reading increase per 1, 000 ft. increase above sea level).
(2) This pressure is at an ambient temperature of 95°F. See the Pressure-Temperature Relationship Chart to determine proper reading at other ambient temperatures.
COMPRESSOR BELT TENSION

Application (1) Tension (Lbs.)
New Belt Used Belt
American Motors 125-155 90-115
Chrysler Corp 120 70
Ford Motor Co 120-160 75-120
General Motors
  Buick 155 90
Cadillac
    Exc. Seville 170 120
Seville 110-140 60-120
  Chevrolet
    Exc. Chevette 135-145 90-100
Chevette 125-150  
  Oldsmobile
    5/16" Belt 80 50
3/8" Belt 150 70
15/32" Belt 165 90
  Pontiac
    4-Cyl. Models 120-130 70-80
V6 & V8 Models 135-145 90-100
(1) Using standard strand tension gauge
EVAPORATOR TEMPERATURE-PRESSURE

Evap. Temp. Low Side Pressure (PSI)
2 10
6 12
10 14
14 16
18 18
20 20
22 22
24 24
27 26
29 28
32 30
36 35
42 40
48 45
53 50
58 55
62 60
66 65
70 70
NOTE: All temperatures given in Fahrenheit.
NOTE: Ambient temperature measure 2-6" in front of condenser.
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