Table 7-1 Sensor Temperature/Resistance Chart - Carrier 69NT40-541-001 Operation And Service

b. Installation:
Install the module by reversing the removal steps.
Torque values for mounting screws (item 2, see
connectors is 0.12 mkg (10 inch-pounds).
7.20.5 Battery Replacement
If required, use tool 07-00418-00.
7.21 TEMPERATURE SENSOR SERVICE
Procedures for service of the Return Recorder, Return Temperature, Supply Recorder, Supply Temperature, Ambi-
ent, Defrost Temperature, Compressor Discharge and Compressor Suction temperature sensors are provided in
the following sub-paragraphs.
7.21.1 Sensor Checkout Procedure
To check a sensor reading, do the following:
a. Remove the sensor and place in a 0°C (32°F) ice-water bath. The ice-water bath is prepared by filling an
insulated container (of sufficient size to completely immerse bulb) with ice cubes or chipped ice, then filling
voids between ice with water and agitating until mixture reaches 0°C (32°F) measured on a laboratory ther-
mometer.
b. Start unit and check sensor reading on the control panel. The reading should be 0°C (32°F). If the reading is
correct, reinstall sensor; if it is not, continue with the following.
c. Turn unit OFF and disconnect power supply.
d. Refer to Section 7.20
e. Using the plug connector marked "EC", that is connected to the back of the controller, locate the sensor
wires (RRS, RTS, SRS, STS, AMBS, DTS, CPDS, OR CPSS as required). Follow those wires to the con-
nector and using the pins of the plug, measure the resistance. Values are provided in
Temperature (C)
0
25
0
25
Due to the variations and inaccuracies in ohmmeters, thermometers or other test equipment, a reading within 2%
of the chart value would indicate a good sensor. If a sensor is defective, the resistance reading will usually be much
higher or lower than the resistance values given.
7.21.2 Sensor Replacement
a. Turn unit power OFF and disconnect power supply.
b. For two wire sensors, cut cable 5 cm (2 inches) from shoulder of defective sensor and discard the defective
sensor only. For three wire sensors cut at 23 cm (9 inches). Slide the cap and grommet off well mounted
sensor and save for possible reuse. Do not cut the grommet.
c. If required, prepare the replacement sensor by cut ting sensor wire(s) back 40 mm (1-1/2 inch). For three
wire sensors the black wire should be cut at the middle length and the red/white wire cut to the shorter
length. (See Figure
T-316
Figure
and remove controller to gain access to the sensor plugs.
Table 7–1 Sensor Temperature/Resistance Chart
Temperature (F)
RRS, RTS, SRS and STS:
AMBS and DTS
7.25)
7.24) are 0.23 mkg (20 inch-pounds). Torque value for the
32
77
32
77
7–32
Table 7–1.
Resistance (Ohms)
32,650 + 91
10,000 + 50
32,650 + 1720
- 1620
10,000 + 450
- 430