Tankless Water Heaters

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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123216
Model#: TK-540X3-NEH
Brand: Takagi
$1,558.00
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123217
Model#: TK-540X3-NIH
Brand: Takagi
$1,558.00
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123218
Model#: TK-240X3-PEH
Brand: Takagi
$1,295.00
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123219
Model#: TK-240X3-PIH
Brand: Takagi
$1,295.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123220
Model#: TK-340X3-PEH
Brand: Takagi
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123221
Model#: TK-340X3-PIH
Brand: Takagi
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123222
Model#: TK-540X3-PEH
Brand: Takagi
$1,558.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123223
Model#: TK-540X3-PIH
Brand: Takagi
$1,558.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123224
Model#: ATO-240HX3-N
Brand: A.O. Smith
$1,453.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123225
Model#: ATO-240HX3-P
Brand: A.O. Smith
$1,453.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123226
Model#: ATO-340HX3-N
Brand: A.O. Smith
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123227
Model#: ATO-340HX3-P
Brand: A.O. Smith
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123229
Model#: ATO-540HX3-P
Brand: A.O. Smith
$1,658.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123230
Brand: State Water Heaters
$1,295.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123231
Brand: State Water Heaters
$1,295.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123232
Brand: State Water Heaters
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123233
Brand: State Water Heaters
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123234
Brand: State Water Heaters
$1,558.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123235
Brand: State Water Heaters
$1,558.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
In-Stock
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123236
Brand: State Water Heaters
$1,295.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k Max BTU/h.
Item#: 123237
Brand: State Water Heaters
$1,295.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123238
Brand: State Water Heaters
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 8 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.8 GPM at 60° F Rise, 4.9 GPM at 70° F Rise. 180k Max BTU/h.
Item#: 123239
Brand: State Water Heaters
$1,421.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
Factory-Direct
EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). Ratings: 9.5 GPM at 40° F Rise, 7.5 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.2 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 123240
Brand: State Water Heaters
$1,558.00
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*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges map apply, see our full shipping policy for more details.
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Tools & Articles
The Ultimate Guide to Water Heaters
How to Pick a Hot Water Heater

Tankless Water Heaters at ACWholesalers


Tankless water heaters are a modern alternative to traditional storage-tank units. A tankless water heater, as the name suggests, does not have a storage tank of hot water waiting to be distributed throughout the home. Instead, it heats only the water that is requested from a faucet or other appliance.

One main advantage of a tankless water heater is the continuous flow of hot water it can produce. Tankless water heaters can heat water within seconds and continue for as long as needed. If the tankless unit is sized correctly to meet the demands of the home, hot water will continue to flow without interruption.

Another benefit of tankless hot water heaters is their compact build. Instead of using obtrusive storage tanks, they simply mount on a wall, thus requiring very little space for installation.

Tankless water heaters are also popular due to their superior levels of efficiency. These units only heat water when it's needed, whereas tank models keep the stored water heated throughout the day and waste energy.

Choosing a Tankless Water Heater


To figure out which tankless water heater best suits a home, it's important to choose the right fuel type, vent type, flow rate (GPM), temperature rise, and uniform energy factor (UEF).

Fuel Type
Tankless water heaters are available in three fuel types: natural gas, liquid propane, and electric.

Vent Type
For indoor-installed tankless units, there are three vent types: power vent, direct vent, and concentric vent. Power venting uses a motor to force exhaust gases outside while pulling in fresh air from the surrounding space. Direct venting uses two separate pipes that run outside for direct intake and exhaust. Concentric venting uses a single, concentric pipe for both intake and exhaust. For outdoor tankless water heaters, no venting is required as the unit vents naturally in the open air.

Flow Rate & Temperature Rise
Flow rate determines how much hot water is needed to serve the targeted fixtures and faucets, which is a number calculated in gallons per minute (GPM). Temperature rise is also a number, which is calculated by subtracting the groundwater temperature from the desired outlet temperature. This difference is how many degrees the water must heat up to reach the desired temperature.

Uniform Energy Factor
A tankless water heater's uniform energy factor (UEF) describes its efficiency. Simply put, the higher the number, the more efficient the model is.