L.B. White Commander Owner's Manual And Instructions page 20

20
Commander Ductable Make-Up Air Heater
7. Check for electrical continuity across the switch
terminals to make sure the contacts have closed.
FIG. 10
RESET BUTTON
MOUNTING
LEGS
Temperature Sensor Probe
The temperature sensor probe is mounted behind the
discharged air louver panel. To test or replace it, perform
the following instructions:
1. If a duct is attached to the discharge ring, disconnect the
duct from the discharge ring.
2. Remove the 12 outer screws securing the ring discharge
panel to the heater. See Fig. 11.
3. Remove the ring discharge panel.
4. Remove the two screws holding the temperature sensor
probe mounting bracket.
FIG. 11
5. Lower the mounting bracket and loosen the two screws
to remove the wires from the temperature sensor probe.
6. Remove the two screws securing the sensor probe to the
mounting bracket.
Owner's Manual •
TERMINAL
SENSING
SURFACE
Commander Ductable Make-Up Air Heater
7. Measure the Ohm resistance across the temp. sen-
sor probe screws as shown in Fig. 12.
8. Compare the reading to the Ohm reading in table 1.
If resistance is different than shown in table, replace
the sensor probe.
9. The probe should be cleaned annually with a dry
clean rag and compressed air.
FIG. 12
Table 1
Temp °F Temp °C
40 4.4
50 10.0
60 15.6
70 21.1
80 26.7
90 32.2
100 37.8
110 43.3
120 48.9
130 54.4
140 60.0
150 65.5
160 71.1
170 76.7
180 82.2
190 87.8
Resistance (Ω)
11210
11020
10826
10630
10433
10234
10034
9830
9624
9413
9199
8983
8766
8550
8337
8130