Calculate Maximum Load
To calculate maximum lo ad po ints, use design load con dition data. If the machi ne full load
cooler temperature dif ference is more than 15° F (8.3 C), estimate the refr ige rant suction and
condensing temperat ures at this difference . Use the proper saturated press ure and temperature
for the particular ref r ige rant used.
Suction Temperat ure:
42 F (5.6 C) = 71.5 psig (521 kPa) saturated refrigerant pressure (HCFC-22)
Condensing Temp erature:
98 F (36.7 C) = 190 psig (1310 k P a) s at urated refrigerant pre s s ur e ( HC FC-22)
Maximum Load T2:
54 – 44 = 10° F (12.2 – 6.7 = 5.5° C)
Maximum Load P2:
190 – 71.5 = 118.5 psid (131 0 – 521 = 789 kPad)
To avoid unnec essary surge preve ntion, add abo ut 10 psid (70 kPad) to P2 from t hes e
conditions:
T2 = 10° F (5.5° C)
P2 = 130 psid ( 900 kPad)