Rheem 018J*Z, Installation Instructions Manual, Page: 22 / 28

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AIR CONDITIONING SYSTEM TROUBLESHOOTING TIPS
AIR CONDITIONING SYSTEM
TROUBLESHOOTING TIPS
SUPERHEAT CALCULATION
1. Measure the suction pressure at the suction line service valve.
3. Measure the temperature of the suction line at the suction line service valve.
4. Compare the temperature of the suction line to the saturated temperature.
5. The difference between saturated temperature and suctin line temperature is the
superheat. Superheat normal range 12° to 15°.
SUBCOOLING CALCULATION
1. Measure the liquid pressure at the liquid line service valve.
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°.
TEMPERATURE PRESSURE CHART
TEMP R-410A
(Deg. F) PSIG
-150 —
-140 —
-130 —
-120 —
-110 —
-100 —
-90 —
-80 —
-70 —
-60 0.4
-50 5.1
-40 10.9
-35 14.2
-30 17.9
-25 22.0
-20 26.4
-15 31.3
-10 36.5
-5 42.2
0 48.4
5 55.1
10 62.4
15 70.2
20 78.5
25 87.5
30 97.2
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
DISCHARGE SUCTION
SUPERHEAT SUBCOOLING
COMPRESSOR
PRESSURE PRESSURE AMPS
Overcharge High High Low High High
Undercharge Low Low High Low Low
Liquid Restriction (Drier) Low Low High High Low
Low Evaporator Airflow Low Low Low Low Low
Dirty Condenser High High Low Low High
Low Outside Ambient Temperature Low Low High High Low
Inefficient Compressor Low High High High Low
Low Low High High Low
Poorly Insulated Sensing Bulb High High Low Low High
SYSTEM PROBLEM
INDICATORS
TABLE 9
TABLE 10
2. Convert the suction pressure to saturated temperature. See Table 9.
2. Convert the liquid line pressure to saturated temperature. See Table 10.
TEV Feeler Bulb Charge Lost
Convert the suction pressure to saturated temperature. See Table 12.
Convert the liquid line pressure to saturated temperture. See Table 13.
TABLE 12
TEMPERATURE PRESSURE CHART
TABLE 13
AIR CONDITIONING SYSTEM TROUBLESHOOTING TIPS