Emerson 3000 Furnace User Manual


 
R407C Refrigerant
78
8.1 Calculating Subcooling
Example
Measure the liquid pressure (e.g., 200 psig). Find the liquid saturation temperature at that pressure
on Table 34 (e.g., 93°F). Measure the temperature of the liquid line (e.g., 90°F). Subtract the actual
temperature from the liquid saturation temperature to obtain the subcooling (e.g., 93 – 90 = 3°F). If
the actual temperature is greater than the liquid saturation temperature, then there is no subcooling,
and the fluid may be a mixture of liquid and vapor.
Why There Are Two R407C Temperature and Pressure Tables
R407C is a blend of refrigerants that exhibits a temperature “glide” of approximately 8 to 12°F
(4 to 7°C). This “glide” is the difference between the liquid and vapor saturation temperatures at a
given pressure. Use the correct table for the saturation temperature you need. Table 33 is for super-
heat or operating controls. Table 34 is for subcooling only.
Table 34 R407C pressure/temperature chart for subcooling only (liquid measurements)
Temperature Pressure Gauge Temperature Pressure Gauge Temperature Pressure Gauge
°F °C Psig kPa °F °C Psig kPa °F °C Psig kPa
36.0 2.2 73 500 59.0 15.0 114 786 94.0 34.4 203 1402
37.0 2.8 74 511 60.0 15.6 116 801 96.0 35.6 209 1444
38.0 3.3 76 522 61.0 16.1 118 815 98.0 36.7 216 1488
39.0 3.9 77 533 62.0 16.7 120 830 100.0 37.8 222 1532
40.0 4.4 79 544 63.0 17.2 123 845 102.0 38.9 229 1578
41.0 5.0 81 556 64.0 17.8 125 860 104.0 40.0 236 1624
42.0 5.6 82 567 65.0 18.3 127 875 106.0 41.1 242 1671
43.0 6.1 84 579 66.0 18.9 129 891 108.0 42.2 249 1720
44.0 6.7 86 591 67.0 19.4 131 906 110.0 43.3 257 1769
45.0 7.2 87 602 68.0 20.0 134 922 112.0 44.4 264 1819
46.0 7.8 89 615 69.0 20.6 136 938 114.0 45.6 271 1870
47.0 8.3 91 627 70.0 21.1 138 954 116.0 46.7 279 1922
48.0 8.9 93 639 72.0 22.2 143 987 118.0 47.8 287 1975
49.0 9.4 95 652 74.0 23.3 148 1021 120.0 48.9 294 2029
50.0 10.0 96 664 76.0 24.4 153 1055 122.0 50.0 302 2085
51.0 10.6 98 677 78.0 25.6 158 1090 124.0 51.1 310 2141
52.0 11.1 100 690 80.0 26.7 163 1126 126.0 52.2 319 2198
53.0 11.7 102 704 82.0 27.8 169 1163 128.0 53.3 327 2256
54.0 12.2 104 717 84.0 28.9 174 1201 130.0 54.4 336 2315
55.0 12.8 106 730 86.0 30.0 180 1239 132.0 55.6 345 2376
56.0 13.3 108 744 88.0 31.1 185 1279 134.0 56.7 354 2437
57.0 13.9 110 758 90.0 32.2 191 1319 136.0 57.8 363 2500
58.0 14.4 112 772 92.0 33.3 197 1360 138.0 58.9 372 2563
--------140.0 60.0 381 2628
NOTE
Use this table for subcooling calculation ONLY. See Table 3 3 for superheat or control
adjustment.