Henny Penny AHC-990, Technical Manual

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Model AHC-990/993
3-5
3-5. AIR TEMPERATURE
PROBE REPLACEMENT
To avoid electrical shock or property damage, move the
POWER switch to OFF and disconnect main circuit
breaker, or unplug cord at wall receptacle.
1. Using a Phillip’s head screwdriver, remove the four screws
securing the front panel.
2. Pull panel down, pull connectors from the back of it, and
remove panel from unit.
3. Unplug the wires to the probe. Figure 3-1.
4. Using a multimeter, or ohmmeter, check across the probe
terminals for the correct ohms using the RTD Resistance
Chart on the following page. If the probe proves faulty,
continue onto step 5.
5. Using a 3/4” wrench, loosen probe strain relief and pull
the probe from the unit. Figure 3-2.
6. Slide new probe through the strain relief, extending the
probe about 1” (25.4 mm) into the cabinet area.
Figure 3-3.
7. Plug probe wires to the unit, tighten the strain relief, and
replace front panel. Unit is now ready for use.
Figure 3-1
Figure 3-2
Figure 3-3
Feb. 2011