Subcooling Calculation - Rheem R-410A Installation Instructions Manual

TABLE 8
TEMPERATURE PRESSURE CHART
TEMP R-410A
(Deg. F) PSIG
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
35 107.5
40 118.5
45 130.2
50 142.7
55 156.0
60 170.1
65 185.1
70 201.0
75 217.8
80 235.6
85 254.5
90 274.3
95 295.3
100 317.4
105 340.6
110 365.1
115 390.9
120 418.0
125 446.5
130 476.5
135 508.0
140 541.2
145 576.0
150 612.8
50

18.8 Subcooling Calculation

1. Measure the liquid pressure at the liquid line service valve.
2. Convert the liquid line pressure to saturated temperature. See Table 8.
3. Measure the liquid line temperature at the liquid line service valve.
—
4. Compare the liquid line temperature to the saturated temperature.
—
5. The difference between saturated temperature and liquid line temperature is the
—
subcooling. Subcooling normal range 9° to 12°.
—
—
—
—
—
—
0.4
5.1
10.9
14.2
17.9
22.0
TABLE 9
26.4 AIR CONDITIONING SYSTEM TROUBLESHOOTING TIPS
31.3
36.5
42.2
SYSTEM PROBLEM
48.4
55.1
62.4
Liquid Restriction (Drier)
70.2
Low Evaporator Airflow
78.5
Dirty Heat Pump
87.5
Low Outside Ambient Temperature
97.2
Inefficient Compressor
TXV Feeler Bulb Charge Lost
Poorly Insulated Sensing Bulb
AIR CONDITIONING SYSTEM
TROUBLESHOOTING TIPS
DISCHARGE
PRESSURE PRESSURE
Overcharge High
Undercharge Low
Low
Low
High
Low
Low
Low
High
INDICATORS
SUCTION
SUPERHEAT SUBCOOLING
High Low High
Low High Low
Low High High
Low Low Low
High Low Low
Low High High
High High High
Low High High
High Low Low
COMPRESSOR
AMPS
High
Low
Low
Low
High
Low
Low
Low
High