Can this heater be used to heat a home?

These heaters can be used in a garage, but they are not approved for use in indoor living spaces. If you have any further questions, please feel free to give us a call! Thanks.

Reznor UDX 105,000 BTU Natural Gas Unit Heater

Customer reviews

Rating:

4.9 out of 5

4.9 out of 5 View All 57 Reviews Add Your Review

Out of stock

Reznor

Out of stock

Model

UDX-100

55753

1 Question Answered

Description

DISCONTINUED

The Reznor UDX-100 has been discontinued in favor of the UDXC-100.

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.

Standard Features

83% AFUE Efficiency
TCORE2 Titanium-Stabilized Aluminized Steel Heat Exchanger
Multi-Try Direct Spark Ignition with Time Lockout
Low Noise Operation with Vibration-Isolated Fan and Venter Motors
Status-Indicating LED Light
7-Segment Display Board for Simple Troubleshooting
Optional Integrated Downturn Nozzle and Integrated Vertical Louvers
2- and 4-Point Suspension Options
External Gas Connection for Ease of Maintenance and Installation
Includes 3 Horizontal Louvers
ETL Approved

Product Note

Reznor UDAP is the legacy model of the Reznor UDX

Product Specs

More Information
Reznor UDX 105,000 BTU Natural Gas Unit Heater
Feature	Spec
SKU	UDX-100
Weight (in lbs)	120
Brand/Manufacturer	Reznor
UPC	663132524969
Additional Information	Air Throw: 59 Feet
Furnace Efficiency / AFUE	80-85%
Heating BTU	105,000 BTU
Maximum CFM	1345
Decibel Level (dBA)	54dB at 15ft
Flue Outlet	4"
Watt	276 Watts
Efficiency	83%
Electrical	115 Volt 1 Phase 60 Hertz
Amperage Requirement	4.3 Amps
Connection	1/2" NG/LP Connection to Gas Valve
Fuel Type	Natural Gas
Height	24 3/4"
Width	27"
Depth	34 9/32"
Warranty	9 Year Heat Exchanger, Burner, and Flue Collection Box Assembly; 4 Year All Electrical and Mechanical Components
Resources	Reznor UDX Installation Guide Reznor UDX Venting Guide Reznor UDX Gas Conversion Guide Reznor Conversion Kit Installation Manual Reznor UDX Replacement Parts List Reznor UDX Downturn Nozzle Instructions Reznor Unit Heater Catalog Reznor Unit Heater Brochure Reznor Warranty Info You will need AdobeÂ® AcrobatÂ® Reader to view PDF documents.
Safety Information	PROPOSITION 65 WARNING This product and many products on our site may contain a chemical know to the state of California to cause cancer or birth defects or other reproductive harm. For more information about Proposition 65 please Click Here.

Reviews 48

Customers Say

Across multiple BTU sizes from 45,000 to 150,000, owners report fast heat-up times—such as raising a 950 sq ft garage from 35°F to 70°F in 15–20 minutes, heating a 60x40x16 shop from 58°F to 70°F in 35 minutes, and maintaining 60°F in a 35,000 cubic foot shop at -11°F—with generally quiet operation. Installation is frequently described as easy, sometimes taking about four hours or reusing existing mounts and connections when replacing older Reznor units, though one incorrect conversion kit and an isolated poor delivery drop-off were noted.

AI Generated from the text of customer reviews

Top reviews

Reznor UDX 60K

Quality
100%

Service
100%

Price
100%

The unit was packaged well, and the installation was straightforward. It’s heated my workshop in Northern Michigan for three seasons now, and it’s been flawless.
Review by Reznor
Posted on 3/5/26
UDX200

Quality
100%

Service
100%

Price
100%

Great looking heaters, and performs wells. great service.
Review by Cory
Posted on 2/25/26
Great support easy transaction

Quality
100%

Service
100%

Price
100%

Great support and quality product will buy fromagain
Review by ohio
Posted on 1/21/26
Reznor 60K BTU

Quality
100%

Service
100%

Price
100%

HVAC Direct delivered on time and unit was incredibly packaged for freight. The unit itself is performing quite well in an uninsulated garage. Keeps everything from freezing. I could not be happier with this purchase and my purchase experience. I will definitely purchase from HVAC Direct when its time to heat my 30x40 barn.
Review by Ypsi Jim
Posted on 1/16/26
Outstanding product

Quality
100%

Service
100%

Price
100%

Got a 46x60 shop with 16ft ceilings the reznor 150,000 btu heats it up fast runs quiet totally surprised how this unit performs
Review by Tb
Posted on 1/12/26
Fast delivery, great price, excellent packaging with zero damage. Easy to install.

Quality
100%

Service
100%

Price
100%

Ordered to replace an old UDAP 45. Basically the same but taller. Fit fine as a hanging unit in the garage. Quieter and warmer output than the old one. Pretty much just unhooked the old one, unmounted it and mounted the new one with the same bolts, reattached connections with a slight modification to the venting. Free shipping and it still got here in less than a week. Overall, great experience with HVACDirect and the price was the lowest I could find.
Review by Dan
Posted on 12/22/25
Great heater

Quality
100%

Service
100%

Price
100%

Easy installation, quiet and works very well!
Review by Corey
Posted on 11/5/25
Great purchase

Quality
100%

Service
100%

Price
100%

We just installed this unit today and it heated my shop up from 58degs. To 70degs. In 35 minutes. The shop is 60x40x16 high.
Review by Nimrod
Posted on 10/23/25

See more reviews

Accessories

FAQ's

Customer Questions

Helpful Articles

Why Choose Reznor Unit Heaters?

Reznor unit heaters are engineered for powerful, energy-efficient heating in commercial, industrial, and residential spaces. With durable construction and advanced technology, these heaters deliver reliable warmth, even heat distribution, and flexible installation options—making them ideal for warehouses, garages, workshops, and more.