Carrier 38VMA Series Service Manual page 10

Table 3 - 38VMA072, 096, 120,144HDS
No. in refrigerant
Symbol
system diagram
A INV
B INV1
C
D FAN A
E FAN B
F EXV A
G EXV B
H EXV C
I PHE
J SV4
K SV7
L ST1
M H-LY1
N L-LY1
O H-PRO
P L-PRO
Q
R
S
T T3
1 T4
2 T5
3 T6
4 T7
5 INV Gas
6 INV1 Gas
Name
Inverter compressor
Inverter compressor
Heat exchanger
Left Inverter fan
Right Inverter fan
Electronic expansion valve
Electronic expansion valve
Electronic expansion valve
Plate Heat Exchanger
Solenoid valve
Solenoid valve
4-way valve
High pressure sensor
Low pressure sensor
High pressure switch
Low pressure switch
Pressure regulating valve
Oil separator
Accumulator
Thermistor (outdoor coil deicer)
Thermistor (Outdoor air)
Thermistor (liquid pipe)
Thermistor (Plate Heat
Exchanger gas pipe)
Thermistor (Accumulator outlet)
Thermistor (INV discharge pipe)
Thermistor (INV1 discharge pipe)
Inverter compressor is operated on frequencies between 20 Hz and 100 Hz.
To exchange heat with ambient environment.
The fan is operated at 13-step rotation speed by using the inverter.
The fan is operated at 13-step rotation speed by using the inverter.
Used to adjust refrigerant volume.
Used to adjust refrigerant volume.
Used to adjust sub-cooling.
Used for sub-cooling liquid refrigerant from the electronic expansion valve.
Used to balance the oil between modules.
This valve opens at a pressure of 565.6 psi to prevent pressure from
increasing.
Used to switch the operation mode between cooling and heating.
Used to detect high pressure.
Used to detect low pressure.
Used to protect the system pressure. When system pressure is too high, the
pressure switch will open. Once the pressure switch is open, compressor
will stop and will restart after 12 minutes.
Used to protect the system pressure. When the system pressure is too low,
the pressure switch will open. Once the pressure switch is open,
compressor will stop, and will restart after 12 minutes.
This valve opens at a pressure of 580 psig to prevent pressure from
increasing, thus resulting in no damage to functional parts due to the
increase of pressure in transportation or storage.
Used to separate oil from high pressure and high temperature refrigerant,
which is pumped out during compression.
Used to store the liquid refrigerant and oil. It can protect the compressor
from liquid slugging.
Used to detect liquid pipe temperature of ODU heat exchanger, determine
defrosting operation, and others.
Used to detect outdoor / ambient temperature.
Detects temperature of liquid pipe after Plate Heat Exchanger.
Detects temperature of gas pipe on the evaporation side of Plate Heat
Exchanger. Used to maintain constant control on superheated of the Plate
Heat Exchanger.
Used to detect gas pipe temperature at the accumulator outlet.
Used to detect discharge pipe temperature. Enables the temperature
protection control of compressor, and others.
Used to detect discharge pipe temperature. Enables the temperature
protection control of compressor, and others.
Major Function
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