78 RT-SVD03G-EN
Zone Sensor Module Testing
Mechanical Zone Sensor Module
Temperature input
Terminals to read voltage: RTRM J6-1, J6-2
Read DC voltage with the sensor attached. If voltage does not appear to be correct, read the
resistance of the circuit, then the sensor itself, to see if a problem exists in the sensor or the wiring.
With the sensor not attached there should be 5.00 VDC at the terminals as shown below.
Problems to look for:
• Miswire/short/open
• Excessive resistance in circuit (corroded or loose connection)
• Sensor inaccurate (should be ± 2F of chart)
• Moisture in sensor (becomes accurate when dry)
• Induced voltage (high voltage wires in same conduit)
Service Tips:
To check for induced voltage, read AC voltage to ground from each sensor wire. Should be less than
1 VAC.
Figure 51. ZSM Testing/voltmeter display
RTRM J6
Heating Setpoint
Mode Input
Cooling Setpoint
Common
Zone Temperature
5.00
DC
Volts
Table 26. Temperature Input
Temp
°F
Resistance
(K ohms)
DC
Volts
Temp
°F
Resistance
(K ohms)
DC
Volts
Temp
°F
Resistance
(K ohms)
DC
Volts
Temp
°F
Resistance
(K ohms)
DC
Volts
40 26.097 3.613 54 17.847 3.203 68 12.435 2.770 82 8.815 2.342
41 25.383 3.585 55 17.382 3.173 69 12.126 2.739 83 8.607 2.312
42 24.690 3.557 56 16.930 3.142 70 11.827 2.708 84 8.404 2.283
43 24.018 3.528 57 16.491 3.111 71 11.535 2.677 85 8.206 2.253
44 23.367 3.500 58 16.066 3.080 72 11.252 2.646 86 8.014 2.224
45 22.736 3.471 59 15.654 3.050 73 10.977 2.616 87 7.827 2.195
46 22.123 3.442 60 15.253 3.019 74 10.709 2.58 88 7.645 2.166
47 21.530 3.412 61 14.864 2.988 75 10.448 2.554 89 7.468 2.137
48 20.953 3.383 62 14.486 2.957 76 10.194 2.523 90 7.295 2.109
49 20.396 3.353 63 14.119 2.926 77 9.949 2.493 91 7.127 2.080
50 19.854 3.324 64 13.762 2.895 78 9.710 2.462 92 6.963 2.052
51 19.330 3.294 65 13.416 2.864 79 9.477 2.432 93 6.803 2.024
52 18.821 3.264 66 13.078 2.832 80 9.250 2.402 94 6.648 1.996
53 18.327 3.233 67 12.752 2.801 81 9.030 2.372 95 6.497 1.969
To Next Page
Loading...
