23
RSMV Technical Guide
TROUBLESHOOTING
Suction Pressure Transducer Testing
Suction Pressure
Transducer Testing for R410A
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 into
the Suction Line of the Compressor.
Use the voltage column to check the Suction Pressure Transducer
while connected to the RSMV Module(s). The VCCX2 and the
RSMV Module(s) must be powered for this test. Read voltage with a
meter set on DC volts. Place the positive lead from the meter on the
SP terminal located on the RSMV Module(s) terminal block. Place
the negative lead from the meter on the ground (GND) terminal
located adjacent to the SP terminal on the RSMV Module(s) 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 SP and GND terminals and
compare it to the appropriate chart depending on the refrigerant you
are using. If the temperature/voltage or pressure/voltage readings do
not align closely with the chart, your Suction Pressure Transducer
is probably defective and will need to be replaced.
See
Table 4
for Suction Pressure Transducer Coil Pressure,
Temperature, and Voltage Chart for R410A Refrigerant testing.
The charts show a temperature range from 20°F to 80°F. For
troubleshooting purposes, the DC Voltage readings are also listed
with their corresponding temperatures and pressures.
Table 4: Coil Pressure/Voltage/Temp for Suction
Pressure Transducers - R410A Refrigerant
Suction Pressure
Transducer Coil
Pressure – Temperature – Voltage
Chart for R410A Refrigerant
Temper
atur
e
°F
Temper
atur
e
ºC
Pr
essur
e
PSI
Signal
DC V
olts
21
-6.1
80.94
1.8
24
-4.4
87.16
1.9
27
-2.8
93.39
2.0
30
-1.1
99.62
2.1
33
0.6
105.84
2.2
36
2.2
112.07
2.3
39
3.9
118.29
2.4
42
5.6
124.52
2.5
44
6.7
130.75
2.6
47
8.3
136.97
2.7
49
9.4
143.2
2.8
52
11.1
149.42
2.9
54
12.2
155.65
3.0
56
13.3
161.88
3.1
59
15
168.10
3.2
61
16.1
174.32
3.3
63
17.2
180.55
3.4
65
18.3
186.78
3.5
67
19.4
193.00
3.6
69
20.6
199.23
3.7
71
21.7
205.46
3.8
72
22.2
211.68
3.9
74
23.3
217.91
4.0
76
24.4
224.14
4.1
78
25.6
230.36
4.2
80
26.7
236.59
4.3
Summary of Contents for RSMV ASM01686
Page 1: ...RSMV Technical Guide ...
Page 31: ...31 RSMV Technical Guide NOTES ...
