• Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350
  • Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350

Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350

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  • Full Interior Kit
  • Since 2009

Reznor UDX 350,000 BTU Natural Gas Unit Heater - NUDX350

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
  • Maximum heating power for very large spaces
    With 350,000 BTU input, this model is built for heavy-duty commercial and industrial environments—ideal for large warehouses, factories, and aircraft hangars where consistent high-output heat is critical.
  • Reliable efficiency at scale
    Delivering around 82–83% AFUE, it offers strong energy performance for its size class, helping balance fuel costs with powerful heating output.
  • Engineered for long-term durability
    The TCORE2® titanium-stabilized aluminized steel heat exchanger is designed to withstand demanding, high-use environments—key for industrial reliability.
  • High airflow & wide coverage
    With airflow reaching up to ~4,400+ CFM and ~90 ft air throw, it ensures broad, even heat distribution across expansive spaces.
  • Quiet operation for its size
    Despite its output, vibration-isolated fan and motor design helps keep noise levels manageable—important for active work environments.
  • Smart diagnostics & maintenance-friendly
    Features like a 7-segment display and LED diagnostics make troubleshooting faster, reducing downtime and service costs.

Q&A

Q1: What size area can the Reznor UDX350 heat?
A: With 350,000 BTU input and ~290,500 BTU output, it’s designed for large warehouses, factories, garages, and commercial spaces requiring high-capacity heating.

Q2: How efficient is the Reznor UDX350?
A: It delivers up to 82–83% AFUE efficiency, balancing strong heat output with energy savings for commercial applications.

Q3: What fuel type does this unit heater use?
A: The UDX350 runs on natural gas and can be converted to propane (LP) using an optional conversion kit.

Q4: Is the UDX350 suitable for industrial use?
A: Yes, it’s built for commercial and industrial heating, including workshops, distribution centers, and large open facilities.

Q5: What makes the Reznor UDX350 durable?
A: It features a TCORE2 titanium-stabilized aluminized steel heat exchanger, designed for corrosion resistance and long service life.

Q6: How powerful is the airflow and heat distribution?
A: The unit delivers up to ~4,400+ CFM airflow with an air throw around 90 feet, ensuring even heating across large spaces.

Q7: Does the UDX350 operate quietly?
A: Yes, it includes a low-noise axial fan and vibration-isolated components, reducing operational noise in large environments.

Q8: Is installation and maintenance easy?
A: The heater is designed with external gas connections, LED diagnostics, and a digital control board, making installation and troubleshooting simple.

Maintenance Tips
  • Keep airflow components clean: Regularly remove dust from propeller fan, louvers, and intake areas to maintain strong air throw (≈90 ft) and efficiency.
  • Inspect heat exchanger yearly: Check the TCORE2® aluminized steel exchanger for cracks or corrosion to ensure safe, high-output operation (≈83% efficiency).
  • Verify ignition & gas system: Test direct spark ignition, gas pressure, and connections to prevent startup failures and uneven heating.
  • Maintain venting system: Ensure power vent and flue are unobstructed to avoid heat loss and dangerous exhaust buildup.
  • Check electrical & diagnostics: Monitor LED indicators and control board for faults; tighten wiring connections to prevent downtime.
  • Inspect fan & motor performance: Listen for unusual noise and ensure vibration-isolated motors run smoothly for consistent airflow.

  • DIY Install

  • OEM-Inspired Fit

  • Air Bag Friendly

  • 3 Year Warranty

  • Custom Colors

  • Work Gear & Pet Friendly

  • Since 2009

Why Truck Owners Choose Seat Covers Over Reupholstery

Traditional Reupholstery TruckLeather Seat Covers
Upfront Cost

$2500-$4000+

$399-$999

Vehicle Downtime

Days or Weeks

None

Risk Level

Permanent, No Undo

Fully Reversible

Best Use Case

Full Restorations

Restoration or Prevention

Resale Value Impact

High Cost to Recover

High ROI

TruckLeather gives you 90% of the visual and comfort upgrade at a fraction of the cost of reupholstery without giving up your truck.

WHEN YOUR TRUCK DESERVES THE BEST. UPGRADE YOUR TRUCK'S INTERIOR WITH THE INDUSTRY DEFINING TRUCK SEAT COVERS WE HAVE REFINED OVER 15 YEARS.

  • Will these work if my seats are already damaged?

    Yes. TruckLeather seat covers are commonly used to cover cracked, faded, or worn-out truck seats while preventing further deterioration.

  • How do these compare to cheaper seat covers?

    Universal covers focus on price. TruckLeather focuses on fit, durability, and long-term protection.

  • Are these permanent?

    No. They’re fully removable and won’t alter your factory seats.

Slip on leather seat covers
Slip on leather seat covers

Easy At-Home Installation

No special tools. No upholstery shop. No risk.

Our seat covers are designed for DIY installation, with step-by-step instructions and support available if you need it. Most customers complete installation in a few hours.

STEP BY STEP INSTRUCTIONS
Red and Black Custom Leather Seat Covers for Ford F150

Your Truck.Your Style.

Custom orders are our jam. Our custom program makes for a truly bespoke experience leaving only your imagination for the thousands of possibilities. If you're looking for the best truck seat covers then look no further!

Clazzio seat cover

Airbag Safe

Our seat cover construction has a high priority for allowing the OEM seat airbags to properly deploy when needed.

The proprietary thread design allows for the SRS systems to continue to function in a collision situation.

Clazzio Leather Covers

Made for your truck.For life.

Our seat covers are made exactly for your interior setup, perfect every time.

We offer most color setups in stock such as all black and all dark gray, however our custom color program is ready for your creative setups.

FAQ

Learn more about our truck seat covers with the frequently asked questions below.

DIY installation instructions are included for your specific application and takes around 2-3 hours for full interior installation.

The specific application specific instructions provided have step by step photos of how to install your new seat covers as well as tips and tricks. 

If you don't feel comfortable installing the seat covers yourself, then any local upholstery shop should be able to install them no problem.

Some vehicles do require cutting in certain spots like the power seat control panel, but nothing too major.

These leather seat covers are 100% slip on seat covers and do not require removal of your existing seat material.

Yes, our seat covers are fully compatible with factory heated and cooled seats.

Clazzio (our manufacturer) offers a 3 year warranty that is honored on any manufacturer defects.  This does not include normal wear and tear that comes with use on these seat covers.

You will receive the full interior seat cover set which includes bottom cushion covers, top cushion covers, head rest covers, and depending on the vehicle, arm rest covers.  It is a total makeover.

They are made by 11i-USA who manufactures these under the name Clazzio. They operate a large dealer system and we are a top nationwide dealer for them.

It depends if you ordered a custom set or not.


If you ordered a set that is in stock, then it will reach you in approximately 5-6 days via UPS ground (continental U.S.). Most all black or all dark gray sets are in stock, but we will let you know upon your order.


If you ordered a custom set, then it will take 8-10 weeks (occasionally longer) to arrive from Japan due to custom manufacturing, freight time, and US customs holding time.

Maybe! Contact us to see if your specific vehicle isn't listed on our site, or if you have any questions about the application.

We do have other applications such as passenger vehicles and two door cars as well. Just contact us!

Need just a bottom cushion replacement or another single piece? Contact us for pricing.

We can also supply just the front or rear seats if that is all you need.

Since our seat covers are manufactured for every application specifically, they account for features like these in your interior. Our development team uses a laser guided measuring system to ensure the best fitment for our seat covers.

For straps to fold down seats, they will include a cutout for those to loop through.  For bottom plastic trim on your front seats, the covers are meant to tuck in to those for a great, OEM+ fitment.

Yes, our seat covers are made with special stitching construction on our per application basis (not universal). The design allow for our covers to break at the specific points where the side airbags will detonate.

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