Introduction
This manual provides comprehensive instructions for the installation, operation, and maintenance of the Johnson Controls A19ACA-14C Line Volt Mechanical Thermostat. The A19 Series Controls are single-stage temperature controls that incorporate environmentally friendly liquid-filled sensing elements. This model is designed for line voltage applications (24 to 277 VAC, 16 Amp).
Note: This product has been discontinued by the manufacturer. Please refer to the specifications section for details.
An image showing the Johnson Controls A19ACA-14C Line Volt Mechanical Thermostat. It features a gray rectangular control unit with a white dial for temperature adjustment on the left side. A white label with 'Johnson Controls' and 'PENN' is visible below the dial. A long, coiled copper capillary tube extends from the bottom of the unit, ending in a copper bulb sensing element.
Safety Information
Before installing or operating this device, please read and understand all safety warnings and instructions. Failure to follow these instructions could result in property damage, serious injury, or death.
- Electrical Hazard: This device operates on line voltage. Disconnect all power to the circuit before installation or servicing. Only qualified personnel should perform electrical work.
- Proper Grounding: Ensure the thermostat is properly grounded according to local and national electrical codes.
- Environmental Conditions: Do not expose the thermostat to water, excessive humidity, or extreme temperatures outside its specified operating range.
- Intended Use: Use this product only for its intended purpose as a temperature control device. Do not modify the unit.
Key Features
- Wide temperature ranges available
- Constant differential throughout the entire range
- Compact enclosure
- Fixed or adjustable differential available
- Variety of sensing element styles
Installation and Setup
Installation of the A19ACA-14C thermostat should only be performed by a qualified electrician or HVAC technician due to its line voltage operation. Ensure all local and national electrical codes are followed.
- Disconnect Power: Before beginning any work, ensure that power to the circuit where the thermostat will be installed is completely disconnected at the main breaker or fuse box. Verify with a voltage tester.
- Mounting: Mount the thermostat in a suitable location, away from direct heat sources, drafts, or other factors that could affect accurate temperature sensing. Use appropriate fasteners to secure the compact enclosure.
- Wiring: Connect the line voltage wiring to the appropriate terminals inside the thermostat enclosure. Refer to the wiring diagram provided with the product for specific connections. Ensure all connections are secure and properly insulated.
- Sensing Element Placement: Carefully route and position the liquid-filled sensing element (capillary tube and bulb) to accurately measure the desired temperature. Avoid kinking or damaging the capillary tube.
- Secure Enclosure: Once wiring is complete and verified, securely close the thermostat enclosure.
- Restore Power: Restore power to the circuit.
Operation
The Johnson Controls A19ACA-14C thermostat features a mechanical knob for temperature control. To operate the unit:
- Set Desired Temperature: Rotate the mechanical knob on the front of the unit to the desired temperature setting. The dial typically indicates temperature in degrees Fahrenheit or Celsius.
- Temperature Response: The thermostat will activate or deactivate the connected heating or cooling system based on the ambient temperature at the sensing element and the set point.
- Differential: The thermostat maintains a constant differential, meaning it will turn on and off within a specific temperature range around your set point to prevent rapid cycling.
Maintenance
The Johnson Controls A19ACA-14C thermostat requires minimal maintenance to ensure optimal performance.
- Cleaning: Periodically wipe the exterior of the thermostat with a soft, dry cloth to remove dust and debris. Do not use abrasive cleaners or solvents.
- Inspection: Annually inspect the wiring connections for tightness and signs of wear. Ensure the capillary tube and sensing bulb are undamaged and properly positioned.
- Professional Check: For critical applications, consider having a qualified technician perform a professional check of the thermostat's calibration and operation periodically.
Troubleshooting
If you experience issues with your A19ACA-14C thermostat, refer to the following common troubleshooting steps:
- Thermostat Not Responding:
- Check if power is supplied to the circuit.
- Verify that the thermostat's internal wiring connections are secure.
- Ensure the temperature setting is appropriate for the desired action (e.g., set lower for cooling, higher for heating).
- Inaccurate Temperature Reading/Control:
- Check the placement of the sensing element. It should be in an area representative of the temperature you wish to control, away from drafts or direct heat.
- Ensure the capillary tube is not kinked or damaged.
- System Cycles Too Frequently/Infrequently:
- The differential setting might need adjustment if your model supports it (some models have fixed differential). Consult a professional if unsure.
If problems persist after attempting these steps, contact a qualified technician for assistance.
Technical Specifications
| Specification | Detail |
|---|---|
| Model Number | A19ACA-14C |
| Brand | Johnson Controls |
| Manufacturer | Johnson Controls Inc |
| Product Dimensions | 3.3 x 2.4 x 10.4 inches; 1 Pounds |
| Controller Type | Mechanical knob |
| Temperature Control Type | Programmable (via mechanical knob) |
| Color | Silver |
| ASIN | B008HQ41LS |
| Date First Available | July 5, 2012 |
| Is Discontinued By Manufacturer | Yes |
What's Included
The product package for the Johnson Controls A19ACA-14C Line Volt Mechanical Thermostat typically includes:
- 1 x Control Unit (Johnson Controls A19ACA-14C Thermostat)
Warranty and Support
For information regarding warranty coverage and technical support for Johnson Controls products, please refer to the documentation provided with your purchase or visit the official Johnson Controls website. As this model has been discontinued, support options may be limited.
