Suction Pressure Transducer Testing; Table 13: Suction Pressure Transducer Chart For R410-A Refrigerant - AAON RSMD Technical Manual

TROUBLESHOOTING

Suction Pressure Transducer Testing

Suction Pressure Transducer Testing
for R410-A Refrigerant
The evaporator coil temperature is calculated by converting the
suction pressure to temperature. The suction pressure is obtained
by using the Suction Pressure Transducer, which is connected to
the suction line of the compressor.
Use the voltage column to check the Suction Pressure Transducer
while connected to the RSMD Module. The VCCX2 and the RSMD
Module must be powered for this test. Read voltage with a meter
set on DC volts. Place the positive lead from the meter on the SP1/
SP2 terminal located on the RSMD Module terminal block. Place
the negative lead from the meter on the ground (GND) terminal
located adjacent to the SP1/SP2 terminal on the RSMD Module
terminal block. Use a refrigerant gauge set and/or an accurate
electronic thermometer to measure the temperature or suction line
pressure near where the Suction Pressure Transducer is connected
to the suction line. Measure the voltage at the SP1/SP2 and GND
terminals and compare it to the appropriate chart depending on the
refrigerant in use. If the temperature/voltage or pressure/voltage
readings do not align closely with the chart, the Suction Pressure
Transducer is probably defective and needs to be replaced.
See the Suction Pressure Transducer, Pressure, Temperature, and
Voltage Chart for R410-A Refrigerant testing. The chart shows a
temperature range from 21.19°F to 80.18°F. For troubleshooting
purposes, the DC voltage readings are also listed with their
corresponding temperatures and pressures.
RSMD Technical Guide
SUCTION PRESSURE TRANSDUCER CHART
FOR R410-A REFRIGERANT
21.19 -6.1
24.49 -4.4
27.80 -2.8
30.99
-1.1
33.89 0.6
36.80 2.2
39.71 3.9
42.30
5.6
44.85 6.7
47.39 8.3
49.94 9.4
52.23 11.1
54.50
12.2
56.76 13.3
59.03 15.0
61.17 16.1
63.19
17.2
65.21 18.3
67.23 19.4
69.24 20.6
71.15 21.7
72.95
22.2
74.76 23.3
76.57 24.4
78.37 25.6
80.18 26.7
Table 13: Suction Pressure Transducer Chart for
R410-A Refrigerant
80.94 1.8
87.16 1.9
93.39 2.0
99.62 2.1
105.84 2.2
112.07 2.3
118.29 2.4
124.52 2.5
130.75 2.6
136.97 2.7
143.20 2.8
149.42 2.9
155.65 3.0
161.88 3.1
168.10 3.2
174.32 3.3
180.55 3.4
186.78 3.5
193.00 3.6
199.23 3.7
205.46 3.8
211.68 3.9
217.91 4.0
224.14 4.1
230.36 4.2
236.59 4.3
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