T921A1191 | Honeywell Proportional Low Voltage Thermostat 24–30VDC, 56–84°F, 135Ω Potentiometer
- Regular price
 - $992.00
 - Sale price
 - $992.00
 - Regular price
 - 
        
$0.00 
Couldn't load pickup availability
Do you need help?
Product Description P/N: T921A1191
Description
The Honeywell T921A1191 is a proportional low-voltage thermostat designed for precise temperature control in heating and cooling systems that utilize valve motors, damper motors, and balancing relays.
Technical Specifications
| Condition | New/Never Used Surplus | 
| Brand | Honeywell | 
| Category | Controls & Indicators | 
| Subcategory | Thermostat | 
| Part Number | T921A1191 | 
| Product Type | Proportional Low Voltage Thermostat | 
| Type | Low Voltage Thermostat | 
| Application | Valve Motors, Damper Motors, Balancing Relays (Heating/Cooling Systems) | 
| Voltage | 24–30 VDC | 
| Control Output | 135-ohm Potentiometer | 
| Scale | Fahrenheit | 
| Temperature Range | 56°F to 84°F (13°C to 28°C) | 
| Mounting | Wall mount (Horizontal orientation) | 
| Dimensions | 5.68 × 3.37 × 2.25 in (144 × 86 × 58 mm) | 
| Housing Color | Gray | 
| Housing Material | Thermoplastic | 
| Control Type | Proportional (Manual Dial) | 
| Ambient Temperature Limits | 32°F to 122°F (0°C to 50°C) | 
| Electrical Connections | Terminal block or pigtail leads (depending on model) | 
| Application Environment | Commercial/Industrial | 
| Indicator Type | Analog scale (Fahrenheit) | 
| Enclosure Rating | Indoor use only | 
| Power Requirement | None (self-powered via control circuit) | 
| Weight | 0.90 lb (0.41 kg) | 
Information About T921A1191
The Honeywell T921A1191 is part of the T900 series of low-voltage proportional thermostats known for their high accuracy and compatibility with pneumatic and electric actuator control systems. It features a 135-ohm potentiometer element, translating temperature changes into proportional voltage or current signals for precise modulation of valve and damper motors. With a sleek gray housing and horizontal wall-mount design, the thermostat is ideal for installations in offices, hospitals, schools, and other commercial spaces requiring reliable, long-term environmental control.
Key Features:
- Proportional Control Thermostat: Provides smooth, linear output signals for modulating devices, enabling stable room temperature without cycling.
 - Low Voltage Operation: Designed for systems operating at 24–30 VDC—ideal for electric valve and damper motor applications.
 - Wide Temperature Range: Adjustable setpoint from 56°F to 84°F (13°C to 28°C) for broad environmental compatibility.
 - Precision Potentiometer Element: Equipped with a 135-ohm potentiometer for accurate proportional output signal response.
 - Universal Compatibility: Works with valve motors, damper motors, and balancing relays in both heating and cooling configurations.
 - Durable Housing: Constructed with a gray thermoplastic case, offering long service life in commercial settings.
 - Horizontal Wall Mounting: Simple installation and aesthetic integration with standard electrical wall boxes.
 - Smooth Manual Adjustment: Easy-to-use temperature dial with Fahrenheit markings for intuitive setpoint control.
 - Stable and Reliable Operation: Mechanical components engineered for minimal wear and extended calibration stability.
 - Compact Design: Low-profile housing suitable for both retrofit and new installations in modern HVAC systems.
 
The T921A1191 offers dependable, energy-efficient proportional temperature regulation for precise indoor climate control in professional and industrial environments.
Description
The Honeywell T921A1191 is a proportional low-voltage thermostat designed for precise temperature control in heating and cooling systems that utilize valve motors, damper motors, and balancing relays.
Technical Specifications
| Condition | New/Never Used Surplus | 
| Brand | Honeywell | 
| Category | Controls & Indicators | 
| Subcategory | Thermostat | 
| Part Number | T921A1191 | 
| Product Type | Proportional Low Voltage Thermostat | 
| Type | Low Voltage Thermostat | 
| Application | Valve Motors, Damper Motors, Balancing Relays (Heating/Cooling Systems) | 
| Voltage | 24–30 VDC | 
| Control Output | 135-ohm Potentiometer | 
| Scale | Fahrenheit | 
| Temperature Range | 56°F to 84°F (13°C to 28°C) | 
| Mounting | Wall mount (Horizontal orientation) | 
| Dimensions | 5.68 × 3.37 × 2.25 in (144 × 86 × 58 mm) | 
| Housing Color | Gray | 
| Housing Material | Thermoplastic | 
| Control Type | Proportional (Manual Dial) | 
| Ambient Temperature Limits | 32°F to 122°F (0°C to 50°C) | 
| Electrical Connections | Terminal block or pigtail leads (depending on model) | 
| Application Environment | Commercial/Industrial | 
| Indicator Type | Analog scale (Fahrenheit) | 
| Enclosure Rating | Indoor use only | 
| Power Requirement | None (self-powered via control circuit) | 
| Weight | 0.90 lb (0.41 kg) | 
Information About T921A1191
The Honeywell T921A1191 is part of the T900 series of low-voltage proportional thermostats known for their high accuracy and compatibility with pneumatic and electric actuator control systems. It features a 135-ohm potentiometer element, translating temperature changes into proportional voltage or current signals for precise modulation of valve and damper motors. With a sleek gray housing and horizontal wall-mount design, the thermostat is ideal for installations in offices, hospitals, schools, and other commercial spaces requiring reliable, long-term environmental control.
Key Features:
- Proportional Control Thermostat: Provides smooth, linear output signals for modulating devices, enabling stable room temperature without cycling.
 - Low Voltage Operation: Designed for systems operating at 24–30 VDC—ideal for electric valve and damper motor applications.
 - Wide Temperature Range: Adjustable setpoint from 56°F to 84°F (13°C to 28°C) for broad environmental compatibility.
 - Precision Potentiometer Element: Equipped with a 135-ohm potentiometer for accurate proportional output signal response.
 - Universal Compatibility: Works with valve motors, damper motors, and balancing relays in both heating and cooling configurations.
 - Durable Housing: Constructed with a gray thermoplastic case, offering long service life in commercial settings.
 - Horizontal Wall Mounting: Simple installation and aesthetic integration with standard electrical wall boxes.
 - Smooth Manual Adjustment: Easy-to-use temperature dial with Fahrenheit markings for intuitive setpoint control.
 - Stable and Reliable Operation: Mechanical components engineered for minimal wear and extended calibration stability.
 - Compact Design: Low-profile housing suitable for both retrofit and new installations in modern HVAC systems.
 
The T921A1191 offers dependable, energy-efficient proportional temperature regulation for precise indoor climate control in professional and industrial environments.