1. Introduction
This manual provides essential instructions for the safe installation, operation, and maintenance of the Reznor UDXC-175 Natural Gas Unit Heater. Please read this manual thoroughly before attempting to install or operate the unit. Retain this manual for future reference.
2. Safety Information
WARNING: Improper installation, adjustment, alteration, service, or maintenance can cause property damage, injury, or death. Read the installation, operating, and maintenance instructions thoroughly before installing or servicing this equipment.
2.1 General Safety Precautions
- Ensure all local codes and ordinances are followed.
- Installation and service must be performed by a qualified installer, service agency, or gas supplier.
- Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.
- Keep the area around the heater clear and free from combustible materials.
2.2 Electrical Safety
- Disconnect power before servicing.
- Ensure proper grounding.
- All electrical wiring must comply with national and local electrical codes.
2.3 Gas Safety
- Verify the gas supply type (Natural Gas) matches the heater's requirements.
- Check for gas leaks after installation using a non-corrosive leak detection solution.
- Do not use an open flame to check for gas leaks.
3. Product Overview
The Reznor UDXC-175 is a 175,000 BTU natural gas-fired unit heater designed for commercial and industrial spaces such as garages, workshops, and warehouses. It features a quiet forced-air system with a low static propeller fan.
Figure 3.1: Front view of the Reznor UDXC-175 Natural Gas Unit Heater.
3.1 Key Features
- Heat Output: 175,000 BTU with 83% thermal efficiency.
- Heat Exchanger: TCORE2 titanium-stabilized aluminized steel.
- Combustion: Patented single-burner design.
- Control System: Integrated circuit board with display, built-in disconnect, and status-indicating LED.
- Mounting: Threaded-nut retainers at four suspension points for ceiling or wall mounting (mounting hardware sold separately).
- Air Circulation: Low static pressure axial fan and power venting.
Figure 3.2: The Reznor UDXC-175 unit heater, highlighting its branding and design.
Figure 3.3: The Reznor UDXC-175 heater installed in a workshop, demonstrating its application.
4. Installation
Proper installation is crucial for the safe and efficient operation of your Reznor UDXC-175 heater. Consult a qualified professional for installation.
4.1 Mounting
The unit is designed for ceiling or wall mounting using the four threaded-nut retainers. Mounting brackets are sold separately. Ensure the mounting structure can support the weight of the heater and any associated components.
Figure 4.1: Various mounting configurations for the Reznor UDXC-175 heater, illustrating ceiling and wall installation points.
4.2 Gas Connection
- Connect the heater to a natural gas supply line.
- All gas piping must comply with local codes and the National Fuel Gas Code (ANSI Z223.1/NFPA 54).
- Install a manual shut-off valve upstream of the unit.
- After connection, perform a leak test.
4.3 Electrical Connection
- Wire the unit according to the wiring diagram provided with the heater and local electrical codes.
- Ensure the power supply matches the unit's requirements (voltage, amperage).
- Connect the thermostat and any other control wiring to the external terminal strip for 24V wiring.
4.4 Venting
The unit is compatible with Category 1 double-wall B-vent pipe. It can be vented vertically through a roof or horizontally through a sidewall. Ensure proper clearances and sealing as per manufacturer instructions and local codes.
5. Operation
5.1 Initial Startup
- Ensure all gas and electrical connections are secure and tested.
- Open the manual gas shut-off valve.
- Turn on the electrical power to the unit.
- Set the thermostat to the desired temperature.
- The integrated circuit board with its 7-segment display and status-indicating LED will provide operational feedback.
5.2 Normal Operation
The heater will cycle on and off as needed to maintain the set temperature. The low static propeller fan will circulate heated air throughout the space.
Figure 5.1: Diagram illustrating the air circulation pattern generated by the Reznor UDXC-175 heater in a room.
5.3 Shutdown
To shut down the unit for an extended period:
- Set the thermostat to its lowest setting.
- Turn off the electrical power to the unit.
- Close the manual gas shut-off valve.
6. Maintenance
Regular maintenance ensures optimal performance and longevity of your heater. Always disconnect power and gas supply before performing any maintenance.
6.1 Annual Inspection (Recommended by Qualified Technician)
- Inspect the heat exchanger for cracks or corrosion.
- Check burner operation and flame characteristics.
- Verify proper operation of safety controls.
- Inspect and clean the fan and motor.
- Check gas pressure and manifold pressure.
- Inspect venting system for blockages or leaks.
6.2 User Maintenance
- Cleaning: Keep the exterior of the unit clean and free of dust and debris. The updated cabinet structure with a removable front face and hinged access door panel with a quarter-turn latch facilitates access for cleaning.
- Clearances: Ensure adequate clearances around the unit are maintained.
7. Troubleshooting
This section provides basic troubleshooting steps. For complex issues, contact a qualified service technician.
| Problem | Possible Cause | Solution |
|---|---|---|
| Heater does not start | No power; Gas supply off; Thermostat setting too low; Safety lockout. | Check circuit breaker; Open gas valve; Adjust thermostat; Reset unit (refer to LED codes). |
| Insufficient heat | Incorrect thermostat setting; Blocked air intake/outlet; Low gas pressure. | Adjust thermostat; Clear obstructions; Contact gas supplier/technician. |
| Unusual noises | Loose components; Fan imbalance; Motor issue. | Inspect for loose parts; Contact service technician. |
| Pilot light/burner won't ignite | No gas; Ignition system fault; Dirty pilot/burner. | Check gas supply; Clean pilot/burner; Contact service technician. |
The integrated circuit board with its display and status-indicating LED can provide diagnostic codes to assist in troubleshooting. Consult the specific diagnostic code list provided with your unit for detailed explanations.
8. Specifications
| Feature | Detail |
|---|---|
| Model Number | UDXC-175 |
| Brand | Reznor (by 1HVAC) |
| Heat Output | 175,000 BTU |
| Thermal Efficiency | 83% |
| Fuel Type | Natural Gas |
| Indoor/Outdoor Usage | Indoor |
| Product Dimensions (D x W x H) | 48.44" x 38.19" x 20.13" |
| Special Features | Integrated Circuit Board with Display, Built-in Disconnect, Patented Single-burner Combustion |
| Mounting | Ceiling or Wall (mounting hardware sold separately) |
9. Warranty and Support
For warranty information and technical support, please refer to the documentation included with your purchase or contact the manufacturer, Reznor, or the distributor, 1HVAC. Keep your purchase receipt for warranty claims.
Contact Information: Refer to the official Reznor or 1HVAC website for the most current support contact details.
