10 Best Natural Gas Garage Heaters (October 2026)

Buying a garage heater on BTU number alone is how most people end up with a unit that is too big, too tall for their ceiling, or not approved for the space. A heater that short-cycles in a small bay wastes fuel, while an undersized one never lifts the temperature on a cold slab. Mounting height, venting, clearances and whether the unit is meant for a garage at all matter as much as output, so the Best Natural Gas Garage Heaters depend on the size of your space and how you can install the unit.

The short answer: the Mr. Heater 50,000 BTU Unit Heater suits most two to three-car garages, the Mr. Heater 80,000 BTU Unit Heater suits larger shops that need more reach, and the Modine Hot Dawg 45,000 BTU suits small garages that want a power-vented, quiet unit. The rest of the list covers large-space forced-air heaters, a compact radiant unit that needs no electricity, and infrared heaters that come with strict mounting and certification limits.

TL;DR: top picks at a glance

• Best overall: the Mr. Heater 50,000 BTU Unit Heater, which heats up to 1,667 sq ft and includes a natural gas to propane conversion kit.
• Best for large shops: Mr. Heater 80,000 BTU Unit Heater, which covers up to 2,667 sq ft and carries a 10-year heat exchanger warranty.
• Best for small garages: Modine Hot Dawg 45,000 BTU, an 80-percent efficient power-vented unit rated for 700 sq ft.
• Best for no-power installs: Heatstar F125444 Radiant Heater, a thermostatic radiant unit that needs no electrical power and covers 500-600 sq ft.

Best Natural Gas Garage Heaters Comparison (October 2026)

#	Product	Best for	Heat Output	Coverage	Weight
1	Mr. Heater 50,000 BTU Unit Heater	Three-car garages	50,000 BTU	1,667 sq ft	60.3 lb
2	Mr. Heater 80,000 BTU Unit Heater	Large workshops	80,000 BTU	2,667 sq ft	78.15 lb
3	Modine Hot Dawg 45,000 BTU	Small garages	45,000 BTU	700 sq ft	60 lb
4	Mr. Heater 125,000 BTU Unit Heater	Big open shops	125,000 BTU	4,167 sq ft	109.13 lb
5	Heatstar F125444 Radiant Heater	No-power garages	25,000 BTU	500-600 sq ft	16 oz
6	SunStar 120,000 BTU Infrared Heater	Contractor-installed spaces	120,000 BTU	1,000 sq ft	52 lb
7	Modine Hot Dawg 125,000 BTU	Quiet large shops	125,000 BTU	3,136 sq ft	125 lb
8	SunStar 80,000 BTU Infrared Heater	High-ceiling buildings	80,000 BTU	Not listed	16 lb
9	Reznor UDXC 105K BTU	Durable shop heating	105,000 BTU	2,000-3,000 sq ft	101 lb
10	HeatStar F180629 60,000 BTU Infrared	Floor-mount radiant	60,000 BTU	Not listed	34 lb

1. Mr. Heater 50,000 BTU Unit Heater: Best Ceiling-Mount Forced-Air Natural Gas Garage Heater for Three-Car Garages

• Heat Output: 50,000 BTU
• Coverage: Up to 1,667 sq ft
• Weight: 60.3 lb
• Mounting: Ceiling mount, 10 ft minimum ceiling height, 8 ft clearance from heater base to floor
• Controls: Works with standard 24-volt or Wi-Fi thermostats (sold separately)

Pros:

• The 50,000 BTU output is rated for roughly a three-car garage, which makes it a sensible fit for the most common garage sizes.
• A natural gas to propane conversion kit and two ceiling angle brackets come in the box, so the fuel can be changed later.
• A high temperature safety shut-off switch and a gas safety flame sensor are built in.
• Buyers generally find it heats a garage quickly and install it without much trouble.

Cons:

• It needs a 10 ft ceiling and 8 ft of clearance below, which rules out many standard 8 ft garages.
• Opinions on noise are mixed, with some finding it quiet and others finding it loud.
• Some buyers report durability problems, including parts coming loose in operation and blown fuses.

Best for: A homeowner with a two or three-car garage and a ceiling of at least 10 ft who wants a straightforward, thermostat-controlled ceiling heater.

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The Mr. Heater 50,000 BTU Unit Heater earns the top spot because its output matches the way most garages are actually used. At 1,667 sq ft of rated coverage it handles a three-car space without the oversizing that comes with the 125,000 BTU class. It weighs 60.3 lb, which is lighter than the 78.15 lb Mr. Heater 80,000 BTU Unit Heater, so a ceiling joist or a pair of brackets has an easier job.

The listed maximum temperature setting is 120 °F, and the heater accepts a standard 24-volt thermostat, so you can keep it at a low holding temperature when the garage is not in use. The heater ships set for natural gas, with the conversion kit included in case you ever switch to propane.

It is the wrong choice for a garage with a low ceiling. If you have under 10 ft of height, the Modine Hot Dawg 45,000 BTU is the better listed fit, since Modine describes it as a low-profile unit that mounts close to the ceiling. Buyers who see the reports of blown fuses and loose parts as a risk should also look at the Reznor UDXC 105K BTU, which carries a longer heat exchanger warranty.

2. Mr. Heater 80,000 BTU Unit Heater: Best High-Output Forced-Air Natural Gas Garage Heater for Large Workshops

• Heat Output: 80,000 BTU
• Coverage: Up to 2,667 sq ft
• Weight: 78.15 lb
• Electrical: 120 volts, 2.3 A
• Warranty: 3 years on parts, 10 years on the heat exchanger

Pros:

• The 80,000 BTU rating covers up to 2,667 sq ft, enough for a deep two-car shop or a small barn.
• The 10-year limited warranty on the heat exchanger is a meaningful protection on the most expensive component.
• It uses the same 24-volt or Wi-Fi thermostat compatibility as the smaller model, so controls are easy to upgrade.
• A conversion kit and two ceiling brackets are included in the box.

Cons:

• It still requires a 10 ft minimum ceiling height and 8 ft clearance below the unit.
• At 78.15 lb it is noticeably heavier than the 50,000 BTU version and needs solid support.
• Thermostat, venting and gas line hardware are not part of the package.

Best for: A workshop owner with a larger floor area or a poorly insulated building who needs more output than a three-car garage heater provides.

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The Mr. Heater 80,000 BTU Unit Heater is the logical step up when the 50,000 BTU model runs out of reach. Its rated coverage of 2,667 sq ft is about 1,000 sq ft more, and the warranty terms are explicitly stated at 3 years on parts and 10 years on the heat exchanger. The fan and burner arrangement is the same ceiling-mounted design, so installation follows the same pattern.

Do not buy it for a standard two-car garage. In a space of 500 to 700 sq ft it will cycle on and off quickly, and the Modine Hot Dawg 45,000 BTU or the Mr. Heater 50,000 BTU Unit Heater will run more steadily. For spaces above 3,000 sq ft, the Mr. Heater 125,000 BTU Unit Heater or the Modine Hot Dawg 125,000 BTU are the better listed fits.

3. Modine Hot Dawg 45,000 BTU: Best Power-Vented 80-Percent Efficient Natural Gas Garage Heater for Small Garages

• Heat Output: 45,000 BTU
• Efficiency: 80 percent
• Coverage: 700 sq ft
• Venting: Power exhaust with small-diameter vent pipe, side-wall or roof
• Weight: 60 lb

Pros:

• The 80-percent efficiency rating means less of the fuel is lost up the vent.
• Power exhaust allows venting through a side wall or the roof with small-diameter pipe, which simplifies the install.
• It is certified for residential, commercial and industrial use, which helps with inspections.
• Field wiring connections and knockouts give quick access for gas and electrical lines.

Cons:

• The 700 sq ft coverage is only enough for a single large bay or a compact two-car garage.
• It needs a 115-volt electrical supply for the power vent, so it will not run during a power cut.
• Thermostat details are Not listed, so plan on confirming controls before installing.

Best for: An owner of a one or two-car garage who wants a quiet, certified, efficient unit and has a spot to run a vent.

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The Modine Hot Dawg 45,000 BTU is the smallest forced-air unit in this list and the most specific to garages. Its low profile and neutral grey cabinet suit a finished garage, and the power exhaust avoids the large-diameter flue runs that gravity-vented heaters need. At 60 lb it weighs about the same as the Mr. Heater 50,000 BTU Unit Heater, but it covers far less area, so choose it for the efficiency and venting rather than raw reach.

It is the wrong pick for any garage larger than around 700 sq ft. A three-car garage is better served by the Mr. Heater 50,000 BTU Unit Heater, while a shop with a 14 ft or higher ceiling should look at the infrared options such as the SunStar 80,000 BTU Infrared Heater.

4. Mr. Heater 125,000 BTU Unit Heater: Best Large-Capacity Ceiling-Mount Natural Gas Garage Heater for Big Open Shops

• Heat Output: 125,000 BTU
• Coverage: Up to 4,167 sq ft
• Weight: 109.13 lb
• Mounting: Ceiling mount with two angle brackets
• Fuel: Natural gas, with a propane conversion kit included

Pros:

• The 125,000 BTU rating covers the largest area of the Mr. Heater range, up to 4,167 sq ft.
• It ships ready for natural gas, with a conversion kit for propane in the box.
• The adjustable temperature feature works with 24-volt and Wi-Fi thermostats.
• Buyers report that it performs as well as an older Reznor unit it replaced and is easy to install.

Cons:

• At 109.13 lb it needs strong framing and often a second person to hang.
• Rated coverage is far beyond what a normal garage needs, so it is easy to oversize.
• Mounting height and clearance requirements are Not listed in the product details.

Best for: A commercial-style garage, barn or open shop of well over 2,000 sq ft where capacity matters more than footprint.

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The Mr. Heater 125,000 BTU Unit Heater follows the same recipe as the smaller models but is built for volume. Its 4,167 sq ft rated coverage compares with 2,667 sq ft for the Mr. Heater 80,000 BTU Unit Heater, and it is the better option for a tall, open shop. Unlike the smaller siblings, the product details do not state a minimum ceiling height, so confirm that with the manual before you cut any brackets.

Skip it for a home garage. A 125,000 BTU unit in a 600 sq ft bay will overheat the space and cycle constantly. The Modine Hot Dawg 125,000 BTU offers similar output with a quieter reputation, but at 125 lb it is heavier still, so the Mr. Heater is the easier unit to hang.

5. Heatstar F125444 Radiant Heater: Best Thermostatic No-Power Radiant Natural Gas Garage Heater for Small Cold Garages

• Heat Output: 25,000 BTU
• Coverage: 500-600 sq ft (about a 2-1/2 car garage)
• Heating Method: Radiant
• Mounting Height: 7 to 9 ft
• Certification: CSA certified

Pros:

• The thermostatic control needs no electrical power, so it works where there is no outlet near the ceiling.
• A mounting range of 7 to 9 ft suits garages that are too low for the forced-air units that need 10 ft.
• CSA certification gives confidence about its use in an attached garage.
• The compact 29.75 in wide body is easy to bracket-mount.

Cons:

• The 25,000 BTU output is the lowest of any heater here, so large or drafty garages will not warm fully.
• Radiant heat warms objects and people in its path rather than the whole air volume.
• Weight is inconsistently stated in the product data, so check it before planning the mounting.

Best for: A owner of a low-ceiling, one or two-car garage with no spare electrical outlet who wants spot warmth for working at a bench.

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What makes the Heatstar F125444 Radiant Heater different is that it needs no electricity. The thermostat is gas-powered, so it keeps working through an outage, something none of the forced-air picks like the Modine Hot Dawg 45,000 BTU can do, because they rely on a fan or power vent.

Radiant heat feels warm quickly on the person standing below, though the air temperature rises more slowly. If you want the whole garage to feel evenly warm, the Mr. Heater 50,000 BTU Unit Heater distributes heat with a fan and covers three times the area. This heater is the better choice only when low ceiling height or a lack of power rules out the others.

6. SunStar 120,000 BTU Infrared Heater: Best Contractor-Installed Infrared Natural Gas Heater for Commercial Spaces

• Heat Output: 120,000 BTU
• Coverage: 1,000 sq ft
• Heating Method: Radiant infrared ceramic
• Mounting: Floor mount, pedestal style
• Weight: 52 lb

Pros:

• The 120,000 BTU infrared output is substantial for a unit that weighs only 52 lb.
• Ceramic infrared heating warms people and surfaces directly without relying on fans.
• The compact body, 23.5 in long and 7.75 in tall, keeps the footprint small.
• Electrical draw is listed at only 0.4 A.

Cons:

• It is not certified or approved for residential use, which excludes most home garages.
• Installation and service must be done by a licensed contractor to local code.
• The product data lists it for outdoor use and a pedestal mount, so it is a poor fit for a typical enclosed garage.

Best for: A commercial buyer working with a licensed contractor who needs a high-output infrared heater in an approved non-residential space.

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The SunStar 120,000 BTU Infrared Heater is the most restrictive purchase here. The warning that it is not certified for residential use is the deciding fact, so a home garage owner should move on. Its 1,000 sq ft coverage is also modest for the output, and the Mr. Heater 80,000 BTU Unit Heater covers more than twice that with less raw BTU.

Choose it only if a contractor has specified it for a commercial space. For any residential installation, the Modine Hot Dawg 45,000 BTU and the Mr. Heater forced-air units are certified for the use and far easier to source parts for.

7. Modine Hot Dawg 125,000 BTU: Best Whisper-Quiet Power-Vented Natural Gas Garage Heater for Large Shops

• Heat Output: 125,000 BTU
• Coverage: 3,136 sq ft
• Efficiency: 80 percent thermal efficiency
• Weight: 125 lb
• Install Clearance: Can sit one inch below the ceiling

Pros:

• The 80-percent thermal efficiency helps lower fuel use at this high output.
• Modine describes the operation as whisper quiet and vibration free.
• It can be installed just one inch below the ceiling, which suits low-ceiling shops.
• The thermostat range runs from 40 °F to 100 °F.

Cons:

• At 125 lb it is the heaviest heater in this list and calls for serious support.
• It draws combustion and makeup air from within the room in its non-separated form.
• The product details are inconsistent about mounting, listing floor mount, so check the install type before ordering.

Best for: A shop owner who wants high capacity and low noise, and who can handle a heavy, power-vented installation.

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The Modine Hot Dawg 125,000 BTU shares the efficiency of the smaller Modine Hot Dawg 45,000 BTU but at nearly three times the output. Its 3,136 sq ft coverage sits below the 4,167 sq ft claimed for the Mr. Heater 125,000 BTU Unit Heater, though the Modine is the one that stresses quiet running and efficiency.

Avoid it for a small garage, and avoid it if your framing is light. The Mr. Heater 125,000 BTU is about 16 lb lighter, and the Reznor UDXC 105K BTU gives similar forced-air capacity at a lower weight.

8. SunStar 80,000 BTU Infrared Heater: Best High-Mount Infrared Natural Gas Heater for Tall Buildings

• Heat Output: 80,000 BTU
• Construction: Aluminized steel with aluminum reflectors
• Minimum Mounting Height: 14 ft above the floor
• Clearances: 49 in above, 99 in below, 49 in at the sides
• Weight: 16 lb

Pros:

• Aluminized steel construction resists corrosion for a long service life.
• Aluminum reflectors are designed to maximize radiant efficiency.
• It can be angle-mounted horizontally and up to 30 degrees.
• A remote control is listed among its features.

Cons:

• The 14 ft minimum mounting height eliminates nearly every residential garage.
• The clearance of 99 in below the heater is a major space requirement.
• Coverage area is Not listed, so sizing it for a space takes extra research.

Best for: An owner of a tall industrial-style shop or barn with a ceiling above 14 ft who wants overhead infrared heat.

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The SunStar 80,000 BTU Infrared Heater is a specialist tool. The 16 lb weight is a fraction of the 78.15 lb Mr. Heater 80,000 BTU Unit Heater, which makes hanging it easy, but the 14 ft mounting height is where most garages fail the test.

For a normal home garage the clearance numbers make it impractical. The Mr. Heater 50,000 BTU Unit Heater works from 10 ft, and the Heatstar F125444 Radiant Heater from as low as 7 ft, so those are better answers for lower ceilings.

9. Reznor UDXC 105K BTU: Best Two-Speed Heat Exchanger Natural Gas Garage Heater for Durable Shop Heating

• Heat Output: 105,000 BTU
• Efficiency: 83 percent thermal efficiency
• Coverage: 2,000-3,000 sq ft
• Weight: 101 lb
• Warranty: 9 years on the heat exchanger, burner and flue collection box, 4 years on electrical and mechanical parts

Pros:

• The 83-percent thermal efficiency is the highest figure listed in this group.
• A titanium-stabilized aluminized steel heat exchanger and single-burner combustion are built for long life.
• The two-speed fan allows lower noise when full airflow is not needed.
• An integrated circuit board with a display and a status LED simplifies diagnosis.

Cons:

• Only the heater is included, and mounting hardware is sold separately.
• It needs a Category 1 double wall B-vent or Category 3 single wall vent pipe, so venting is a bigger job.
• At 101 lb it is heavy, and it needs a 115-volt supply.

Best for: A shop or garage owner who values long warranty coverage and efficiency and is comfortable with a professional-grade installation.

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The Reznor UDXC 105K BTU reads like a commercial heater adapted for garages. It lists a 9-year warranty on the heat exchanger and burner and a 4-year warranty on electrical and mechanical parts. Compare that with the Mr. Heater 80,000 BTU Unit Heater, with a 10-year heat exchanger warranty but only 3 years on parts.

The extra work is in venting and mounting. If you want a simpler job, the Mr. Heater models include brackets, and the Modine Hot Dawg 45,000 BTU uses small-diameter vent pipe. This Reznor suits the buyer who accepts that complexity in return for efficiency and durability.

10. HeatStar F180629 60,000 BTU Infrared: Best Floor-Mount Radiant Natural Gas Heater for Occasional Spot Heating

• Heat Output: 60,000 BTU
• Heating Method: Radiant
• Mounting: Floor mount
• Weight: 34 lb
• Coverage: Not listed

Pros:

• The 34 lb weight is lighter than any forced-air unit here.
• The 60,000 BTU output is meaningful for a radiant heater.
• A floor-mount form avoids drilling into the ceiling.
• The product data describes it as noiseless.

Cons:

• Coverage, certification and clearance details are Not listed, so suitability for a garage is unconfirmed.
• The product data points to home office and living areas for use rather than garages.
• Installation information is thin, which makes comparison with other heaters difficult.

Best for: A buyer who has confirmed the code and clearance requirements for their space and wants a portable-weight radiant unit.

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The HeatStar F180629 60,000 BTU Infrared sits last because so little is documented. Where the Mr. Heater 50,000 BTU Unit Heater states coverage, mounting height and safety shut-offs, this unit gives only output, weight and heating method.

It is the wrong choice if you need certainty about garage suitability. The Heatstar F125444 Radiant Heater is a radiant alternative with stated coverage, mounting range and certification, and it is the safer starting point for radiant heat.

Buyer's Guide: How to Choose the Right Natural Gas Garage Heater

The core trade-off is between capacity and fit. A bigger heater warms faster, but the garage's ceiling height, venting path and electrical supply decide which units can be installed at all, and a smaller unit that fits correctly will outperform a larger one that cannot be mounted properly.

Before choosing, check these project details:

• Floor area: Measure the garage in square feet and compare it with each heater's rated coverage, as in 1,667 sq ft for the Mr. Heater 50,000 BTU Unit Heater.
• Ceiling height: Confirm the minimum mounting height, which runs from 7 ft for the Heatstar F125444 Radiant Heater to 14 ft for the SunStar 80,000 BTU Infrared Heater.
• Venting route: Decide whether you can vent through a side wall or roof, and with what pipe type.
• Power supply: Check whether a 115 or 120-volt outlet is available near the heater location.
• Residential approval: Verify that the unit is certified for the building type, since the SunStar 120,000 BTU Infrared Heater is not approved for residential use.

Forced-Air Versus Radiant Heat

Forced-air unit heaters such as the Mr. Heater 80,000 BTU Unit Heater and the Modine Hot Dawg 125,000 BTU blow warm air through the space, which raises the overall temperature and is the better choice for general use. Radiant models like the Heatstar F125444 Radiant Heater warm people and objects directly, which feels effective at a workbench but leaves the air cooler.

If you weld, grind or work with sparks, keep radiant and forced-air heaters well away from the work area and make sure you have proper protection such as welding gloves. Heater clearances to combustible materials matter more in a busy shop than in a storage garage.

Sizing BTU Output to Garage Space

A rule of thumb is to match rated coverage to the floor area, with some margin for poor insulation. The Mr. Heater 50,000 BTU Unit Heater suits roughly 1,000 to 1,600 sq ft, while the Modine Hot Dawg 45,000 BTU is rated for 700 sq ft. A heater far above your needs will cycle on and off and wastes fuel.

Larger shops with high ceilings and open doors benefit from higher outputs such as the Mr. Heater 125,000 BTU Unit Heater with a 4,167 sq ft rating. Heat loss through uninsulated doors can reduce the effective coverage, so insulation and weatherstripping are worth more than a bigger heater.

Venting and Installation Requirements

Natural gas heaters need a safe way to exhaust combustion gases, and the options vary. The Modine Hot Dawg 45,000 BTU uses a power exhaust with small-diameter vent pipe through a side wall or roof, while the Reznor UDXC 105K BTU requires Category 1 double wall B-vent or Category 3 single wall pipe. Always have gas lines and venting checked against local code.

Fuel storage also matters. Keep gasoline cans and fuel-powered tools, including a gas string trimmer, well away from any heater with a flame. A dedicated storage spot on the far side of the garage avoids vapor exposure near the burner.

Ceiling Height and Mounting Clearances

Ceiling-mounted heaters need space above and below. The Mr. Heater 50,000 BTU Unit Heater and its 80,000 BTU sibling both require 10 ft of ceiling height and 8 ft of clearance from the heater base to the floor. The Modine Hot Dawg 125,000 BTU is described as installable one inch below the ceiling, which helps in lower buildings.

Plan the wall layout as well. Hoses, shelving and a water hose reel should sit clear of the heater's side and rear clearances. Infrared units like the SunStar 80,000 BTU Infrared Heater list 49 in at the sides and 99 in below, which is a much larger keep-out zone.

Frequently Asked Questions About Natural Gas Garage Heaters

What size natural gas garage heater do I need?

Match the heater's rated coverage to your garage's floor area. The Mr. Heater 50,000 BTU Unit Heater covers up to 1,667 sq ft, so it suits a two or three-car garage, while the Modine Hot Dawg 45,000 BTU is rated for 700 sq ft. Poor insulation or a high ceiling means you should step up to the Mr. Heater 80,000 BTU Unit Heater.

Can I install a natural gas garage heater myself?

Some buyers handle installation of the Mr. Heater units, which come with ceiling brackets, but gas lines and venting must meet local code. The Reznor UDXC 105K BTU and the SunStar 120,000 BTU Infrared Heater specifically call for professional installation or have strict venting rules. When in doubt, use a licensed gas fitter.

Do natural gas garage heaters need electricity?

Most forced-air units do, because they need power for the fan and controls. The Modine Hot Dawg 45,000 BTU needs 115 volts and the Mr. Heater 80,000 BTU Unit Heater lists 120 volts. The Heatstar F125444 Radiant Heater is the exception, with thermostatic control that needs no power.

Which natural gas garage heater is quietest?

Modine describes both the Modine Hot Dawg 45,000 BTU and the Modine Hot Dawg 125,000 BTU as quiet, and the 125,000 BTU model is called whisper quiet. The Reznor UDXC 105K BTU has a two-speed fan for lower noise. Buyers have mixed opinions on the Mr. Heater 50,000 BTU Unit Heater.

Can a natural gas garage heater run on propane?

The Mr. Heater models, including the Mr. Heater 125,000 BTU Unit Heater, ship with a conversion kit in the box. The Modine Hot Dawg 125,000 BTU is listed for propane or natural gas. Check each model's manual before converting.

What ceiling height do I need for a garage heater?

The Mr. Heater 50,000 BTU Unit Heater and Mr. Heater 80,000 BTU Unit Heater need at least 10 ft. The Heatstar F125444 Radiant Heater mounts at 7 to 9 ft, which suits lower garages. The SunStar 80,000 BTU Infrared Heater needs 14 ft.

Final Verdict: Which Natural Gas Garage Heater Should You Buy?

Best Natural Gas Garage Heaters for most garages start with Mr. Heater 50,000 BTU Unit Heater: it delivers 50,000 BTU, covers up to 1,667 sq ft and includes a propane conversion kit. Its main weakness is the 10 ft ceiling requirement and some reports of durability problems, so check your ceiling height before ordering.

For alternatives, pick by use case. The Mr. Heater 80,000 BTU Unit Heater and the Mr. Heater 125,000 BTU Unit Heater suit larger shops, with the 125,000 BTU model reaching 4,167 sq ft. The Modine Hot Dawg 45,000 BTU and Modine Hot Dawg 125,000 BTU are the quiet, efficient choices at 80 percent thermal efficiency, and the Reznor UDXC 105K BTU is the pick for long warranty coverage at 83 percent efficiency.

The specialist picks cover narrower situations. The Heatstar F125444 Radiant Heater runs without electricity at 25,000 BTU, the SunStar 120,000 BTU Infrared Heater and SunStar 80,000 BTU Infrared Heater need contractor installation or very high ceilings, and the HeatStar F180629 60,000 BTU Infrared lacks key published details. If you are still undecided, measure your floor area and ceiling height first, and choose the smallest certified forced-air unit that covers the space.