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                HONEYWELL FURNACE CONTROLS
 ELECTRONIC FAN TIMER FOR OIL FURNACES
Integrates control of all burner and circulator fan operations in an oil furnace. This control is the central wiring point for most of the electrical components in the furnace. The basic purpose of the ST9103A is to monitor the thermostat for heat, cool, and fan demands and run the oil burner primary control and up to a two- speed circulating fan as required. It also monitors a limit switch string, which energizes the circulating fan whenever the limit switch opens.
   Electronic air cleaner and humidifier convenience terminal connec- tions are provided as an option. A means for operating continuous indoor air circulation is also available as an option.
ST9103A1002
ELECTRONIC FAN TIMER FOR GAS WARM AIR FURNACES
                   Integrate control of all combustion blower and circulating fan operations in a gas warm air appliance. This control is the central wiring point for most of the electrical compo- nents in the furnace. monitors the thermostat for heat, cool and fan demands, runs the induced draft blower motor and runs the circulating fan (up to two speeds) as needed. It also monitors limit switch strings and energize separate ignition control systems through spst pressure switches. It features a field-adjustable heat fan-on delay, a field-adjustable heat fan-off delay, a field-adjustable cool fan-on delay and a fixed cool fan-off delay. Electronic air cleaner (EAC) and humidifier (HUM) convenience terminal connections are provided as an option. Continuous low speed indoor air circulation is also provided. In short, this one little unit packs a big punch.
                    The ST9120U can replace any ST9101, ST9120 or ST9141A model.
SPECIFICATIONS
 Electrical Ratings:
Power Voltage Requirements: 18 to 30 Vac, 60 Hz. Contact Ratings:
Thermostat Load: 0.10A plus ignition system load. On/Off Delay Settings:
    Heat Speed:
Delay On: Field-adjustable, 30 or 60 seconds. Delay timing starts when gas valve is energized.
Delay Off: Field-adjustable, 60, 100, 140 or 180 seconds. Delay timing starts when gas valve is deenergized.
Cool Speed:
Delay On: Field Adjustable, 4 or 30 seconds.
Delay Off: Fixed, 30 seconds.
Timing Tolerance: Larger of ±5% or ±2 seconds.
Post Purge Timing: 5 seconds.
ST9120U1011
                          268 Part numbers and illustrations are for identification only © 1971 - 2018 w.d. armstrong corp.
 












































































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