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HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 20 (HVAC SYSTEM - GENERAL SERVICING)PRESSURE-TEMPERATURE RELATIONSHIP
1999 GMC Forward Control 5.7 R, Automatic

Pressure-Temperature Relationship

1999 GMC Forward Control 5.7 R, AutomaticSECTION Pressure-Temperature Relationship
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A refrigerant, when confined in an enclosed space, increases in pressure as the temperature increases. Conversely, if the temperature is lowered, the pressure also decreases.

Depending on temperature, a corresponding pressure will exist in a such an enclosed space. For example, at 70°F (21.1°C), a gauge will indicate about 71.0 psi (5.0 kg/cm2 . Refer to the R-134A PRESSURE-TEMPERATURE RELATIONSHIP  table to see this relationship.

R-134A PRESSURE-TEMPERATURE RELATIONSHIP

Temperature °F (°C) (1) psi (kg/cm2 )
20 (-6.7) 18 (1.3)
30 (-1.1) 26 (1.8)
40 (4.4) 35 (2.5)
45 (7.2) 40 (2.8)
50 (10.0) 45 (3.2)
55 (12.8) 51 (3.6)
60 (15.6) 57 (4.0)
65 (18.3) 64 (4.5)
70 (21.1) 71 (5.0)
75 (23.9) 79 (5.6)
80 (26.7) 87 (6.1)
85 (29.4) 95 (6.7)
90 (32.2) 104 (7.3)
95 (35.0) 114 (8.0)
100 (37.8) 124 (8.7)
110 (43.3) 147 (10.3)
120 (48.9) 171 (12.0)
130 (54.4) 199 (14.0)
140 (60.0) 229 (16.1)
150 (65.6) 263 (18.5)
160 (71.1) 300 (21.1)
(1) Pressure readings are provided as a general guideline and may not represent actual readings.
RENDER: 1.0x

NO RELATED

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