Issue:
CGM OA Temperature Sensor Failure
Resolution:
| CGM OA TEMP SENSOR FAILURE |
- This diagnostic occurs when there is not a valid signal on the CGM OA Temp Input
- All IntelliPak chillers ship with an outside air temperature sensor as standard
- The sensor has to be in the range of approximately 55 F to 209 F (approximately 500,000 to 700 ohms)
- This is an automatic reset diagnostic
- The diagnostic will clear when the module measures a valid resistance
Here are the steps for Intellipak Air-Cooled Chiller
Step #1 Wiring Error
Verify the wiring between the OA Sensor and the CGM (1U48). Refer to unit schematics for wire numbers and connections. If the wiring checks good, proceed to the next step.
Step #2 Sensor Checkout
Disconnect the OA sensor wires from the CGM (1U48). Check the resistance reading of the sensor and wiring at the plug connector. Compare the resistance reading to the above chart. If the values are not correct, double check for wire errors. Replace sensor if none are found. If the values are correct, proceed to the next step.
|
TEMPERATURE (F) |
RESISTANCE (kW) |
TEMPERATURE (F) |
RESISTANCE (kW) |
|
-40 |
346.1 |
71 |
11.60 |
|
-30 |
241.7 |
72 |
11.31 |
|
-20 |
170.1 |
73 |
11.03 |
|
-10 |
121.4 |
74 |
10.76 |
|
-5 |
103.0 |
75 |
10.50 |
|
0 |
87.56 |
76 |
10.25 |
|
5 |
74.65 |
77 |
10.00 |
|
10 |
63.80 |
78 |
9.76 |
|
15 |
54.66 |
79 |
6.53 |
|
20 |
46.94 |
80 |
9.30 |
|
25 |
40.40 |
85 |
8.25 |
|
30 |
34.85 |
90 |
7.33 |
|
35 |
30.18 |
100 |
5.82 |
|
40 |
26.22 |
105 |
5.21 |
|
45 |
22.85 |
110 |
4.66 |
|
50 |
19.96 |
120 |
3.76 |
|
55 |
17.47 |
130 |
3.05 |
|
60 |
15.33 |
140 |
2.50 |
|
65 |
13.49 |
150 |
2.05 |
|
66 |
13.15 |
160 |
1.69 |
|
67 |
12.82 |
170 |
1.40 |
|
68 |
12.50 |
180 |
1.17 |
|
69 |
12.19 |
190 |
0.985 |
|
70 |
11.89 |
200 |
0.830 |
Step #3 CGM Checkout
Connect a known resistance in the valid range to OA sensor input to the CGM (1U48) directly. Using the Human Interface (1U65) check the status of the OA Temp Sensor. If the diagnostic clears and the correct temperature is displayed, recheck wiring and sensor. If the Human Interface does not display the correct value with the resistor connected to the board, replace the CGM (1U48).
.
Notes:
Changes:
Other Question/Problem/Cause Statements:
- CGM OA Temperature Sensor Failure
- Is there a resistance chart to check the temperature sensors?
- Need resistance for temperature sensors?
Facts:
- Intellipak Air-Cooled Chiller 20-60
- Air-Cooled Chiller - Intellipak (CGAC, CGAF)
Document Identifier: DOC-74372
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.