Calculate Maximum Load

To calculate maximum load points, use design load condition data. If the machine full load cooler temperature difference is more than 15° F (8.3 C), estimate the refrigerant suction and condensing temperatures at this difference. Use the proper saturated pressure and temperature for the particular refrigerant used.

Suction Temperature:

42 F (5.6 C) = 71.5 psig (521 kPa) saturated refrigerant pressure (HCFC-22) Condensing Temperature:

98 F (36.7 C) = 190 psig (1310 kPa) saturated refrigerant pressure (HCFC-22) Maximum Load ΔT2:

54 – 44 = 10° F (12.2 – 6.7 = 5.5° C) Maximum Load ΔP2:

190 – 71.5 = 118.5 psid (1310 – 521 = 789 kPad)

To avoid unnecessary surge prevention, add about 10 psid (70 kPad) to ΔP2 from these conditions:

ΔT2 = 10° F (5.5° C)

ΔP2 = 130 psid (900 kPad)

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Carrier PC211 specifications Calculate Maximum Load