Thermo Products OPB (24 ユーザーズマニュアル
All installations and services must be performed by qualified service personnel.
Now, the degree of superheat can be calculated.
55
°F (Suction line temperature at outlet of evaporator)
- 47
°F (Saturation temperature for R410A at 68 PSIG)
-----------------------
8
8
°F = Degree of evaporator superheat.
Example 4:
Problem: Additional refrigerant measurements are made on the cooling system
of our typical OPB installation. The liquid line pressure, measured at the
condenser unit, liquid line, charging port, is 340 PSIG. The temperature of the
refrigerant (R410A) at the evaporator liquid line connection is measured as 95
of our typical OPB installation. The liquid line pressure, measured at the
condenser unit, liquid line, charging port, is 340 PSIG. The temperature of the
refrigerant (R410A) at the evaporator liquid line connection is measured as 95
°F.
What is the degree of subcooling for this system?
Solution: Calculate the pressure of the refrigerant at the evaporator liquid line
connection. With the estimated refrigerant pressure and measured temperature
at the same point, tabulated data on R410A from the refrigerant manufacturer,
or ASHRAE, can be used to evaluate the degree of subcooling.
connection. With the estimated refrigerant pressure and measured temperature
at the same point, tabulated data on R410A from the refrigerant manufacturer,
or ASHRAE, can be used to evaluate the degree of subcooling.
340 PSIG (Liquid line pressure measured at condenser)
+ 0 PSIG (Added for pressure drop of liquid line)
------------------
340 PSIG = Estimated pressure of refrigerant at evaporator inlet
From the R410A pressure/temperature chart, at 340 PSIG, the saturation
temperature is approximately 105
temperature is approximately 105
°F
Now, the degree of subcooling can be calculated.
105
°F (Saturation temperature for R410A at 340 PSIG)
- 95
°F (Suction line temperature at outlet of evaporator)
------------------
10
10
°F = Degree of condenser subcooling
72