14
Subject to change without notice.
low pressure, low temperature refrigerant vapor
entering the suction side of the compressor into
a high pressure, high temperature gas at the
discharge side of the compressor. The function
of the compressor also pumps the refrigerant
through the piping and components within the
refrigeration system.
Condenser Coil
The condenser receives the high-pressure high-
temperature gas from the compressor after it
passes through the vibration eliminator. As the
condenser blower draws the ambient air across
the fins and tubes of the condenser coil and
the high-pressure high-temperature gas enters
the condenser coil, the gas starts to condense
back into liquid state. At the outlet piping of the
condenser coil, the gas has been turned back into
liquid refrigerant and flows toward the receiver.
Evaporator Coil
As the liquid refrigerant passes through the
expansion valve, the liquid refrigerant’s pressure
is regulated downward. This significant change
in pressure causes a drop in temperature of
the refrigerant. When the warmer ambient air
is drawn over the cooler evaporator coil, the
warmer or latent heat is exchanged. As the heat
is being exchanged, the exchange of heat energy
causes the liquid refrigerant to boil into a vapor
and greatly reducing the temperature of the air on
the outlet side of the coil. The liquid refrigerant
is converted into the lower temperature, lower
pressure refrigerant causing it to changing into a
vapor state.
Flooded Condenser (Option)
The Flooded Condenser Option is used for
discharge refrigerant pressure control during
low outdoor ambient conditions. As the outdoor
ambient temperature starts to fall below 60
degrees and cooling is still required within the
space being conditioned, the compressor system’s
head pressure starts to fall. As the compressor’s
refrigerant discharge pressure starts to fall below
290 psig, the valve mechanically modulates open
to bypass some of the discharge gas around the
condenser coil directly into the liquid receiver.
As this gas enters the receiver, it backs the flow
of the converted liquid refrigerant back into the
condenser coil rendering part of the coil inactive.
This increases the discharge pressure to help
maintain system capacity.
Filter Drier
The filter drier, filters loose particles, moisture and
possible brazing residue from the system. If the
unit starts tripping on low pressure cutout and the
refrigerant line is frosted up to the outlet of the
filter drier, check the refrigerant pressure drop
across the filter drier and replace the filter drier if
necessary.
Hot Gas Bypass Valve
The hot gas bypass valve has a pressure port to
monitor the compressor system’s suction pressure.
If the suction pressure falls below 104 psig, the
hot gas bypass valve mechanically modulates
open to maintain the 104 psig set point. This valve
modulates under conditions such as low space
loads such as non comfort cooling applications,
low temperature applications, low volume comfort
cooling applications (minimal occupants).
Sight Glass
A liquid sight glass is located before the liquid
line solenoid valve. During the cooling mode of
operation, pure liquid should flow through the
liquid sight glass. The liquid refrigerant will appear
clear enough to see the back of the inside of the
sight glass. Flashing (bubbles) will appear in
the sight glass during the first minute or two of
operation until the expansion valve fully adjusts.
If flashing is constant during the cooling mode, it
may be an indication the unit is short of refrigerant.
There may also be some flashing during hot gas
bypass operation. See the Troubleshooting Chart
for further details.
