- 11 -
6.
Use of the encapsulated pressure control (if applicable)
Fixed suction pressure setting: Cut in = 32 psig; Cut out = 10 psig
Fig. 10 Fixed Pressure Control
7.
Use of the condenser fan control (if applicable for low ambient kit)
Head pressure setting: Cut in=170 psig; Cut out=120 psig; Differential=50 psig
It closes on rise of pressure. It may need to adjust the setting in the field to avoid fan
short cycle.
8.
Use of the crankcase heater (if applicable for low ambient kit)
The crankcase heater is installed around the lower part of the compressor and
shall be turned on all the time. The heater is self-modulated.
CAUTION:
TURN OFF THE COMPRESSOR BEFORE POWER THE CONDENSING UNIT.
ONLY TURN ON THE COMPRESSOR AFTER THE CONDENSING UNIT HAS
BEEN POWERED FOR 24 HOURS.
9. Pressure, Superheat and Subcooling Readings
CAUTION:
THE VALVES MUST BE IN THE MIDDLE POSITIONS TO READ PROPERLY.
Complaint Possible
Causes
a. High suction pressure and low head pressure
Zero superheat and zero subcooling
b. High suction pressure and low head pressure
Low superheat and low subcooling
c. High suction pressure and high head pressure
Low superheat and high subcooling
d. High to normal suction pressure and high head pressure
Low subcooling
e. High suction pressure and high head pressure
Low superheat and low subcooling
a. Compressor may be bad
b. Expansion valve opened, too
much oil
c. Overcharge
d. Non-condensable
gas
e. Air restricted, dirty condenser,
bad condenser fans
