Thermodisc Switch | 110°F High-Speed Fan Limit Control for Jensen & US Stove Furnaces | TDF110-20F / 80389

USSC 80389 thermo-disc 110 degree / 20 degree differential  Limit Control - Part # 80389 Temperature Range: Cut-in - 110º F  Cut-out - 130ºF 20f Open to Rise Therm-O-Disc Part Number 60T11-610044 DISTRIBUTION FAN (1) HI-SPEED PT# 80389 ENERGIZES WHEN UNIT IS FIRED AGGRESSIVELY ONLY. 80389 High Speed Thermo-disc for multiple brands including: Jensen Stove 24AF, 24AG and 24AZ Jensen US Stove 80389 High Speed Thermodisc 24A 24AF 24AJ Wood Furnace USSC Wall mounted thermostat requests heat...electrical contact occurs. 2. Current is sent through relay, rheostat, 170 degrees thermo limit disk to activate draft fan. 3. Relay...electrical switching device, Rheostat...current (voltage) reducer increases or de- creases draft fan R.P.M. 170 degrees limit disk...breaks off electrical current at 170 degrees (limit disk) Draft fan...small fan that activates fire, increasing fire temperature. 4. Upon firebox temperature rise due to air from draft fan, distribution fan is activated at approximately 110 degrees air temperature, 600 CFM of air at 110 de- grees. 5. 110 volts (main electrical line) is sent to left side of 140 degrees thermo disk (3 prongs) current passes through 140 degrees disk to 110 degrees disk. Current simply waiting for 110 degrees so it can pass through and activate normal speed function of distribution fan. (blue wire) 6. If 110 degrees firebox air temperature is not main- tained snap disk terminates current to distribution fan. Should firebox temperature air reach 140 degrees cur- 7. rent is directed to activate high speed portion 1300 CFM of air. Current travel from prong 1 to prong 2 on 140 degrees disk to activate high speed portion (black wire). Distribution Capacitor: Reduces amps required to ac- 8. tivate distribution fan. Varistor: Provides even flow of current to snap disk, 9. prevents electrical surges, provides longer life of snap disk. Transformer: Reduces voltage 110 volts to 12 volts for 10. thermostat usage. Generally hums a bit. The above is somewhat basic, however, it's offered so you can understand your furnaces electrical functions and en- joy it more. USSC