Carrier 17/19EX - Manual (Page 156)

If, after configuring a value for these points, surge prevention is operating too soon or too late
for conditions, these parameters should be changed by the operator.
Example of configuration: Machine operating parameters
Refrigerant used: HFC-134a
Estimated Minimum Load Conditions:
44 F (6.7 C) LCW
45.5 F (7.5 C) EWC
43 F (6.1 C) Suction Temperature
70 F (21.1 C) Condensing Temperature
Estimated Maximum Load Conditions:
44 F (6.7 C) LCW
54 F (12.2 C) ECW
42 F (5.6 C) Suction Temperature
98 F (36.7 C) Condensing Temperature
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.