Honeywell T991F1009 Modulating Temperature Reset Controller. Automatic outdoor reset controllers for air or liquid.

Features

• Micro Switch end switch cycles burner on and off at low fire; T991 then modulates burner as required
• Designed for use with V9055; can be used with any series 90 motor.
• Ambient compensated.
• Setpoint adjustment on front of case.
• Switch makes 1 F (0.6 C) above end of throttling range.
• Mount using three holes in the back of the case

• Description: Modulating Temperature Reset Controller, 70 F to 140 F
• Application Provides on/off and modulating control of water or air temperature in ducts or tanks
• Type: Modulating Remote bulb
• Output Type: analog and relay
• Analog Output: One 135 Ohm Potentiometer
• Output: 1 SPST
• Reset Ratio: 1.0 to 1.0
• Voltage: 24 Vac to 30 Vac
• Frequency : 50 Hz
• Frequency: 60 Hz
• Color: GrayDimensions (in.): 5-7/8 in. high x 4-1/8 in. wide x 2-3/16 in. deep
• Dimensions (mm): 149 mm high x 105 mm wide x 56 mm deep
• Sensor Element: Copper bulb
• Number of Sensor Inputs : 2
• Capillary Length (ft): Indoor: 10 ft, Outdoor: 30 ft
• Capillary Length (m) : Indoor: 3 m, Outdoor: 9.1 m
• Bulb Size (in.): 1/2 in. diameter x 4-3/16 in. long
• Bulb Size (mm) :13 mm diameter x 107 mm long
• Setpoint Temperature Range (F) :70 F to 140 F
• Setpoint Temperature Range: 21 C to 60 C
• Maximum Operating Temperature (F): 265F
• Maximum Operating Temperature (C) : 129 C
• Throttling Range (F): 11 F
• Throttling Range (C): 6 C
• Differential Temperature (F): 4 F additive
• Differential Temperature (C): 2.2 C additive
• Comments: Indoor bulb temperature plus outdoor bulb temperature must not exceed 265 F (129 C).