Our Most Energy Efficient Heaters for 2021

The arrival of fall means that millions of families will be turning up the heat at home. However, that comes at a cost: heating accounts for roughly 40% of the typical household’s energy bill, according to the Department of Energy. And the colder it gets, the higher the bill, with the average home spending $581 on natural gas, $1,520 on heating oil, and $1,174 in electrical costs.

To help lower the bills in this uncertain economic climate, we’ve come up with an updated guide to our most energy efficient heaters for 2021.

About Energy Efficiency

First we need to discuss efficiency. While it may sound straightforward, energy efficiency is actually measured differently for different types of heaters. But on a comparative basis, gas heaters are the most efficient while electrical heaters are the least efficient.

Vented gas heaters

Vented gas furnaces measure energy efficiency using AFUE, or annual fuel utilization efficiency rating. AFUE is represented as a percentage of the amount of fuel that is turned into usable heat. 

For example, a gas furnace with a 90% AFUE means it outputs 90 BTUs of heating for every 100 BTUs of natural gas it uses. The remainder is lost in the form of exhaust. A higher AFUE means higher efficiency.

A midlevel furnace typically has an 80-85% AFUE rating, while high-efficiency heaters go up to 90-97%.

Most efficient vented gas heater for 2021:

Rinnai EX22CT 21500 BTU EnergySaver Direct Vent Wall Furnace

One of our most popular heaters, Rinnai’s EX22CT vented gas heater provides a balance between efficiency and affordability.  it has an 81% efficiency rating while coming in at a lower price compared to other brands. Rinnai’s EnergySaver modulating technology constantly monitors room temperature changes as low as 1°F. It then adjusts the heat accordingly, making it highly efficiency and instantly responsive to fluctuations.

The heater can generate up to 21,500 BTUs, perfect for larger rooms with an outside wall. It has a built-in programmable thermostat, 2 timer settings, and it can even be paired to a WiFi thermostat for smart home control, even when you’re away from the house.

Ventless gas heaters

Vent-free gas heaters do not vent the exhaust outside, so they are all rated 99.9% efficient. This makes ventless gas heaters the most efficient type of gas heater.

However, do note that they are not ideal for every situation. Since they don’t vent the exhaust to an outside conduit, ventless heaters are not suitable for small or confined spaces such as bedrooms, where they can cause carbon monoxide poisoning.

Another thing to consider is that vent-free heaters can generate moisture to the air. This makes them less ideal for humid climates or for those who are sensitive to high humidity.

Finally, vent-free gas heaters top out at 30,000 BTUs. This means they should be limited to smaller areas, as the heater will not give off enough warmth to heat a larger space.

In addition, it should be noted that vent-free heaters are not suitable for higher altitudes due to the reduced oxygen levels. 

Our top-selling ventless gas heaters for 2021:

Fan Convector Gas Heater:

Rinnai FC824 24,000 BTU Vent Free Fan Convector Gas Heater

Rinnai’s FC824 is an ideal option for hard to heat rooms. This convection fan heater can evenly distribute the 22,000-24,000 BTUs of warmth it can generate compared to other heater types. The fan is pretty silent too, humming along at just 30dB in low and 44dB at high setting.

In addition, it boasts a modulating gas valve and variable speed blower, which ensures the heater uses only the exact amount of gas needed to heat the space. And as a vent-free heater, it doesn’t need to be placed on an exterior wall, and there is virtually no heat loss.

Infrared heater:

HearthRite HRW30TN 30000 BTU Infrared/Radiant Vent Free Gas Heater with Thermostat – Natural Gas

This natural gas-powered heater uses infrared to warm a room, similar to how sunlight warms up objects. It can generate up to 30,000 BTUs, and since it uses natural gas, it can continue to function through a power outage. An oxygen depletion sensor continually monitors oxygen levels and automatically shuts off the heater when it drops to unsafe levels.

It comes with a thermostat and standard wall mount. Optional accessories include a floor stand and blower.

Blue flame heater:

Empire Comfort Systems BF-30W 30,000 BTU Blue Flame Vent-Free Gas Heater with Thermostat

If you want rapid heat, the BF30 is the answer. This blue flame heater warms the room starting with objects, including the wall where it’s mounted. Rooms with reversible-bladed ceiling fans can also benefit from this heater since it will help spread the heat more quickly throughout the room.

The modulating hydraulic thermostat can be set between 8,500 to 30,000 BTU and will automatically work to maintain the temperature. It comes in natural gas and liquid propane versions.

Most efficient warehouse heater for 2021:

Reznor UEZ-130 130,000 BTU High Efficiency Gas Fired Separated Combustion Unit Heater

Reznor’s UEAS heaters are the most efficient warehouse heaters in the world. One of their renowned features is separated combustion chambers, where the air input is drawn from outside or from another room. This ensures fresh, uncontaminated air free of harmful particulate matter.

The UEZ-130 is rated for 93% and comes with a full fan guard and fully gasketed door panel with safety door switch. The primary heat exchanger is made from the company’s patented TCore3 titanium-stabilized aluminized steel for unsurpassed longevity and durability. The secondary heat exchanger, meanwhile, uses a MacroChannel design and ½” PVC coupling pipe, for convenient installation and maintenance. 

Compared to the earlier series, the newly designed UEZ family boasts rounded corners that eliminate sharp edges, and a sleek outer shell without any visible screws or fasteners.

Electric heaters

Electric heaters cost more than gas heaters to operate and require a lot of power, which makes them highly inefficient compared to natural gas and propane heaters.

However, there are some forms of electric heat that are better than others. Infrared heating panels use special technology to heat an object directly versus the air. This requires less power and makes users feel warm faster compared to other types of electric heaters.

Our best-selling infrared electric heater:

Bromic Heating BH0420033 Tungsten Smart-Heat 6000 Watt Electric Heater

This infrared heater can service up to 160 sq. ft. of space using a spectral reflector for excellent radiant heat distribution. It’s compatible with smart control systems and boasts a precise dimming function. It comes with wall and ceiling mount brackets and can be installed in low clearance spaces as low as 8 ft.

Conclusion

To recap, vent-free gas heaters are the most efficient heaters, but they’re not ideal for confined spaces or high humidity environments. Vented gas heaters with an AFUE rating of 90 or higher are versatile and can be installed in rooms of virtually any size, depending on the BTU. (For assistance with calculating BTUs, consult our Heating BTU Calculator.)

At Total Home Supply, we offer free shipping on all of our heaters to anywhere in the contiguous United States. Be sure to check out our selection of gas heaters and contact us if you have any questions about our products. We’re here to help you find an efficient heating solution for your home.