Heat Controller RSE1318-1A - Page 20

19
TABLE 9
AIR CONDITIONING SYSTEM TROUBLESHOOTING TIPS
AIR CONDITIONING SYSTEM
TROUBLESHOOTING TIPS
SUPERHEAT CALCULATION
1. Measure the suction pressure at the suction line service valve.
2. Convert the suction pressure to saturated temperature. See Table 8.
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.
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°.
TABLE 8
TEMPERATURE PRESSURE CHART
TEMP R-22
(Deg. F) PSIG
-150 *29.4
-140 *29.1
-130 *28.5
-120 *27.7
-110 *26.6
-100 *25.1
-90 *23.0
-80 *20.2
-70 16.6
-60 *11.9
-50 *6.1
-40 0.6
-35 2.6
-30 4.9
-25 7.5
-20 10.2
-15 13.2
-10 16.5
-5 20.1
0 24.0
5 28.3
10 32.8
15 37.8
20 43.1
25 48.8
30 54.9
35 61.5
40 68.5
45 76.1
50 84.1
55 92.6
60 101.6
65 111.3
70 121.4
75 132.2
80 143.7
85 155.7
90 168.4
95 181.8
100 196.0
105 210.8
110 226.4
115 242.8
120 260.0
125 278.1
130 297.0
135 316.7
140 337.4
145 359.1
150 381.7
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
TXV Feeler Bulb Charge Lost Low Low High High Low
Poorly Insulated Sensing Bulb High High Low Low High
SYSTEM PROBLEM
INDICATORS