Filter
Top Products
30 TRG-TRC005-EN
notes
period four
Expansion Devices
In a typical TXV application, the outlet of the valve is connected to the
distributor. A remote bulb is attached to the suction line, where it senses the
refrigerant vapor temperature leaving the evaporator. This bulb is charged with
refrigerant and as heat is transferred from the suction line to the bulb, the
refrigerant inside the bulb vaporizes. The resulting refrigerant vapor pressure is
transmitted through a tube to the space above a diaphragm in the TXV.
The pressure of the refrigerant vapor leaving the evaporator is transmitted to
the space beneath the diaphragm through an external equalizing line that is
tapped into the suction line downstream of the bulb.
Finally, the valve contains an adjustable spring that applies a force to the lower
side of the diaphragm.
TXV Operation
external equalizer
external equalizer
remote
remote
bulb
bulb
evaporator
evaporator
spring
spring
suction
suction
line
line
distributor
distributor
diaphragm
diaphragm
Figure 45