HHT Heat N Glo 146-500 Wall Thermostat Instruction Manual

1. Introduction

This manual provides essential information for the safe and efficient installation, operation, and maintenance of your HHT Heat N Glo 146-500 Wall Thermostat. This genuine OEM replacement part is designed for use with Hearth & Home gas stoves and fireplaces, compatible with both LP (liquid propane) and NG (natural gas) units. The thermostat operates on a millivolt system, eliminating the need for batteries.

Figure 1: HHT Heat N Glo 146-500 Wall Thermostat. This image shows the front view of the white, rectangular wall-mounted thermostat with a manual control dial.

2. Safety Information

Please read and understand all safety instructions before installing or operating this thermostat. Failure to follow these instructions could result in property damage, personal injury, or death.

Electrical Hazard: Disconnect power to the fireplace or heating appliance before installation or servicing to prevent electrical shock.
Qualified Personnel: Installation and servicing should be performed by a qualified service technician.
Gas Appliance Safety: Always refer to the gas fireplace or stove manufacturer's manual for specific wiring diagrams and safety precautions related to the gas appliance.
Proper Wiring: Ensure all wiring connections are secure and comply with local electrical codes.
Intended Use: Use this thermostat only for its intended purpose with compatible millivolt gas fireplaces and stoves.

3. Package Contents

Verify that all items are present before beginning installation:

HHT Heat N Glo 146-500 Wall Thermostat (1)
Mounting Hardware (screws, wall anchors) (1 set)
Instruction Manual (this document) (1)

4. Setup and Installation

This thermostat is designed for wall-mounted, wired installation and operates on a millivolt system. No external power supply or batteries are required for its operation, as it draws power directly from the millivolt generator in your gas fireplace.

Choose Location: Select an interior wall location, away from direct sunlight, drafts, or heat sources (like the fireplace itself), which could affect temperature readings. The recommended height is approximately 5 feet (1.5 meters) from the floor.
Disconnect Power: Before starting, ensure the gas supply to the fireplace is turned off and any electrical power to the fireplace is disconnected.
Mount Thermostat:
- Carefully separate the thermostat cover from its base.
- Position the thermostat base on the wall at your chosen location.
- Mark the mounting screw holes.
- Drill pilot holes if necessary and secure the base to the wall using the provided mounting hardware.
Wire Connections:
- Run low-voltage thermostat wire (typically 18-gauge, 2-conductor) from your gas fireplace's millivolt valve terminals to the thermostat's terminals.
- Connect one wire from the fireplace to one terminal on the thermostat.
- Connect the second wire from the fireplace to the other terminal on the thermostat.
- Ensure connections are tight and secure. Polarity is generally not critical for millivolt systems, but refer to your fireplace manual for specific instructions.
Reassemble and Test:
- Carefully snap the thermostat cover back onto its base.
- Restore gas and electrical power to the fireplace.
- Turn the thermostat dial to a setting above the current room temperature to test if the fireplace ignites.
- Turn the dial below the current room temperature to ensure the fireplace turns off.

Important: Always consult your specific gas fireplace or stove installation manual for detailed wiring diagrams and safety procedures. Incorrect wiring can damage the thermostat or the fireplace control system.

5. Operating Instructions

The HHT Heat N Glo 146-500 Wall Thermostat features simple manual control for your gas fireplace.

Setting the Temperature: Rotate the manual control dial (analog display) to your desired room temperature. The thermostat will activate the fireplace when the room temperature falls below your set point and deactivate it when the room temperature rises above the set point.
Turning Off the Fireplace: To turn off the fireplace, rotate the dial to its lowest setting or to the "OFF" position if marked.
Continuous Operation (if applicable): Some fireplace systems may have a separate switch for continuous pilot operation. This thermostat controls the main burner based on temperature.

This thermostat provides basic temperature regulation. For advanced features or programming, a different type of thermostat would be required.

6. Maintenance

The HHT Heat N Glo 146-500 Wall Thermostat requires minimal maintenance to ensure reliable operation.

Cleaning: Periodically wipe the exterior of the thermostat with a soft, damp cloth. Do not use abrasive cleaners or solvents.
Airflow: Ensure that the vents or openings on the thermostat casing are not obstructed by dust or debris, as this can affect temperature sensing accuracy.
Connections: Annually, or if experiencing issues, have a qualified technician check the wiring connections at both the thermostat and the fireplace valve for tightness and corrosion.

7. Troubleshooting

If your fireplace system is not operating as expected with the thermostat, refer to the following common issues and solutions:

Problem	Possible Cause	Solution
Fireplace does not turn on when thermostat is set above room temperature.	No gas supply to fireplace. Pilot light is out. Loose or incorrect wiring connections. Faulty millivolt generator in fireplace. Thermostat malfunction.	Check gas valve and supply. Relight pilot light according to fireplace manual. Verify all wiring connections are secure. Consult fireplace manual or a qualified technician. Test thermostat continuity (if equipped and knowledgeable) or replace.
Fireplace does not turn off when thermostat is set below room temperature.	Thermostat wiring shorted. Thermostat malfunction. Fireplace valve issue.	Inspect wiring for damage or shorts. Test thermostat or replace. Consult a qualified technician for fireplace valve inspection.
Inaccurate temperature readings.	Thermostat located in a drafty area or near heat source. Vents obstructed.	Relocate thermostat if possible, or shield from drafts/heat. Clean thermostat vents.

For persistent issues, contact a qualified HVAC technician or the fireplace manufacturer's support.

8. Specifications

Feature	Detail
Brand	HHT
Model Number	146-500
Controller Type	Push Button / Manual Dial
Special Feature	Low Voltage, Millivolt Operation
Color	White
Specific Uses	Gas Fireplace Temperature Control
Temperature Control Type	Manual
Connectivity Technology	Wired
Power Source	Hardwired (Millivolt)
Item Weight	3.45 ounces (0.1 Kilograms)
Shape	Rectangular
Display Type	Analog
Control Method	Touch (Dial)
Mounting Type	Wall Mount
Backlight	No
Wattage	10 watts (operational)
Package Dimensions	6.02 x 5.51 x 1.38 inches
UPC	652174688753
ASIN	B08FVDYVSS

9. Warranty Information

This HHT Heat N Glo 146-500 Wall Thermostat is a genuine OEM replacement part. Warranty coverage, if any, is typically provided by the manufacturer, HHT (Hearth & Home Technologies), and may vary. Please retain your proof of purchase. For specific warranty terms and conditions, refer to the documentation provided with your original fireplace unit or contact HHT customer service directly.

10. Customer Support

For technical assistance, troubleshooting beyond this manual, or inquiries regarding parts and service, please contact the manufacturer:

Manufacturer: HHT (Hearth & Home Technologies)
Refer to your original fireplace manual for specific contact details or visit the official HHT website for support information.
When contacting support, please have your product model number (146-500) and the model number of your fireplace readily available.

HHT 146-500