B. RESISTIVE TEMPERATURE DEVICE (RTD)
1.RTD (Resistive Temperature Device)
The gas dryer utilizes five (5) Resistive Temperature Devices (RTD's);
•One (1) RTD probe is used to control the drying temperature in the tumbler (basket).
•One (1) RTD probe is used to detect an over temperature condition in the dryers' intake.
•One (1) RTD probe is used to monitor for an over temperature condition in the over burner.
•One (1) RTD probe is used to detect an over temperature condition in the dryers' exhaust.
•One (1) RTD probe is used to monitor for an over temperature condition in the sprinkler system.
The steam dryer utilizes two (2) or three (3) Resistive Temperature Devices (RTD's);
•One (1) RTD probe is used to control the drying temperature in the tumbler (basket).
•One (1) RTD probe is used to detect an over temperature condition in the dryers' exhaust.
•The third RTD probe is present if the dryer is equipped with the "optional" sprinkler system.
The RTD probe operates as a resister that increases in resistance as temperature increases. At 32º F (0º C) the RTD probe reads 100 ohms (100 Ω ) with the probe out of circuit. The RTD probe has predetermined temperature to resistance characteristics (i.e., at 77º F [25º C] the RTD probe should read 109.73 ohms [109.73 Ω ]).
a. RTD (Resistive Temperature Device) Replacement
NOTE: For RTD (Resistive Temperature Device) probe locations refer to the three (3) illustrations on page 80.
1)Discontinue water supply to the dryers' sprinkler system.
2)Discontinue electrical service to the dryer.
3)Remove probe(s) junction box cover.
4)Identify wire(s) from defective RTD probe(s).
5)Mark the position of the wire(s) in the terminal block that will be removed for proper reinstallation.
6)Remove wire(s) from terminal block.
7)Loosen compression fitting(s) and remove defective probe(s).
8)To install new probe(s), reverse Step #7 thru Step #3.
9)Reestablish electrical service to the dryer.
10)Reestablish water supply to the dryers' sprinkler system.
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