Johnson & Starley Thermistors
The thermistor increases the current resistance as it gets colder The printed circuit board sends a current to the thermistor and can tell whether a decrease or increase in heat is needed by the relative resistance provided by the thermistor.
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JOHNSON AND STARLEY 1000-0506735 OVERHEAT STAT (PRE-UPGRADE ONLY)
Part No: 1690709 / MPN: 1000-0506735