Reznor UDX 125,000 BTU Propane Unit Heater - NUDX125,N1036538R
Reznor model UDX gas-fired unit heaters are great for space heating applications. These units are power vented to eliminate heat losses up the flue pipe. Each heater features a two-tone black and white powder coated, scratch-resistant paint scheme and has clean rounded corners and edges with no visible screws or fasteners. For air circulation, the UDX series utilize an axial propellor fan.
Features
- 83% AFUE Efficiency
- TCORE2 titanium stabilized aluminized steel heat exchanger
- Multi-try, direct spark ignition with time lockout
- Vibration/noise isolated fan and venter motors designed for low noise operation
- External status indicating LED that blinks if there is a problem that needs service
- 7-segment display board that shows fault code for quick and easy troubleshooting
- Optional integrated downturn nozzle and integrated vertical louvers
What our Experts Think
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Powerful mid‑range propane heating
With 125,000 BTU and ~83 % AFUE, this propane UDX heater delivers robust, cost‑effective heat for large garages, workshops, and light‑commercial spaces where smaller units struggle.
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Built for long‑term reliability
The TCORE2 titanium‑stabilized aluminized steel heat exchanger enhances durability and corrosion resistance, boosting service life even in demanding environments.
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Efficient, power‑vented design
Power venting reduces heat lost up the flue and improves overall system efficiency compared with non‑vented alternatives.
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Low noise & solid airflow
The vibration‑isolated axial propeller fan keeps operation quieter and provides wide air distribution to help reduce cold spots in large bays or open areas.
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Service‑friendly features
Built‑in 7‑segment diagnostics, LED status indicators, and external gas connections simplify maintenance and troubleshooting—cutting service time and costs.
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Flexible install options
Standard ceiling or wall suspension points make installation adaptable across different layouts, and optional downturn or vertical louvers let you tailor airflow direction.
Q&A
Q: What is the heating capacity of the Reznor UDX125?
A: It delivers 125,000 BTU input (~125 MBH) of powerful heat, perfect for medium garages, workshops, warehouses, and commercial spaces.
Q: What fuel type does the NUDX125 use?
A: Designed for propane (LP) operation with ETL approval for indoor commercial/industrial heating.
Q: What efficiency rating does this unit offer?
A: The UDX125 achieves ~83 % AFUE thermal efficiency, helping reduce fuel costs.
Q: What heat exchanger technology does it include?
A: It features a TCORE2 titanium‑stabilized aluminized steel heat exchanger for durability and corrosion resistance.
Q: Does it require special venting?
A: Yes — it’s power‑vented to eliminate heat loss up the flue and improve performance.
Q: How does the airflow system work?
A: Uses a low‑static axial propeller fan for efficient and even air distribution.
Q: Is the operation quiet?
A: Built with vibration‑isolated fan and venter motors for low‑noise heating.
Q: Is installation and maintenance easy?
A: Designed with external gas connection, LED status indicators, and 2‑ or 4‑point suspension options for simplified installation and servicing.
Maintenance Tips
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Annual heat exchanger inspection: Check the TCORE2® titanium‑stabilized aluminized steel exchanger for soot, rust or cracks and gently clean surface dust — keeping combustion efficiency high and avoiding overheating.
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Burner & flame assembly care: Remove debris from burner tubes and inspect propane flame for stable, mostly blue color — dirty burners reduce efficiency and can cause sooting.
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Clear venting & combustion air paths: Ensure power‑vent flue and intake are unobstructed to maintain proper draft and safe exhaust of combustion gases.
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Fan, blower & motor maintenance: Clean axial propeller fan and motor housing; check for imbalance, worn bearings or loose set screws to prevent airflow restriction.
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Electrical & ignition checks: Tighten wiring and inspect/clean direct spark ignitor and flame sensor for reliable starts; use LED diagnostics for early fault detection.
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Inspect gas supply & connections: Check propane line fittings for leaks and proper regulator function — address any issues before operation.
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Keep exterior clean: Remove dust and debris from cabinet, louvers and intake screens to support airflow and efficiency.
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Schedule annual professional service: A certified HVAC technician should test combustion, safety controls, and temperature rise to ensure safe, efficient performance.
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