Four-Way Valve
The Four-Way Valve (4WV) also known as a Reversing Valve
is a component only used on Heat Pumps. This device is used
to direct the discharge gas from the compressor into the indoor
coil (Heating Mode) or outdoor coil (Cooing Mode). This device
is defaulted to cooling and when de-energized will direct the
discharge gas into the outdoor coil.
Figure 29: Four-Way Valve
By-Pass Solenoid Valve
The By-Pass Solenoid Valve (SVB) is used to “short-circuit”
the high pressure compressor discharge to the low pressure
suction side during start-up. This increases compressor
longevity by minimizing starting torque and inrush current.
Figure 30: By-pass Solenoid Valve
Receiver Solenoid Valve
The Receiver Solenoid Valve (SVR) is used to “bleed off”
refrigerant vapor from the top of the Receiver during pump
down or the transition between mechanical heating and
defrost. Cooling only units will not have this component, only
Heat Pumps .
Figure 31: Receiver Solenoid Valve
Compressor Discharge Gas
Compressor Discharge Gas
Suction Vapor
Suction Vapor
to Compressor
to Compressor
Cooling Mode:
Cooling Mode:
Suction Vapor from
Suction Vapor from
Indoor Coil
Indoor Coil
Heating Mode:
Heating Mode:
Discharge Gas
Discharge Gas to
to
Indoor Coil
Indoor Coil
Cooling Mode:
Cooling Mode:
Discharge Gas to
Discharge Gas to
Outdoor Coil
Outdoor Coil
Heating Mode:
Heating Mode:
Suction Vapor
Suction Vapor from
from
Outdoor Coil
Outdoor Coil
Short Circuit between
Short Circuit between
High Pressure Discharge
High Pressure Discharge
and Low Pressure Suction
and Low Pressure Suction
By-Pass
By-Pass
Solenoid
Solenoid
Valve
Valve
Vapor Bleed
Vapor Bleed
from top of
from top of
Receiver to
Receiver to
Compressor
Compressor
Suction
Suction
Receiver
Receiver
Solenoid
Solenoid
Valve (EVI)
Valve (EVI)
IM-1125-13 • REBEL ROOFTOPS
28
www.DaikinApplied.com
Refrigeration System