Tankless Water Heaters

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EnergyStar Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 5.8 GPM at 40° F Rise, 4.6 GPM at 50° F Rise, 3.8 GPM at 60° F Rise, 3.3 GPM at 70° F Rise. 109k Effective BTU/h.
Item#: 31852
Model#: NRC661DV-NG
Brand: Noritz
$1,052.69
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EnergyStar Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 7.1 GPM at 40° F Rise, 5.8 GPM at 50° F Rise, 4.9 GPM at 60° F Rise, 4.2 GPM at 70° F Rise. 148k Effective BTU/h.
Item#: 31855
Model#: NRC711OD-LP
Brand: Noritz
$1,295.62
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EnergyStar Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 7.1 GPM at 40° F Rise, 5.8 GPM at 50° F Rise, 4.9 GPM at 60° F Rise, 4.2 GPM at 70° F Rise. 157k Effective BTU/h.
Item#: 31856
Model#: NRC711DV-NG
Brand: Noritz
$1,295.62
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EnergyStar Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 5.8 GPM at 40° F Rise, 4.6 GPM at 50° F Rise, 3.8 GPM at 60° F Rise, 3.3 GPM at 70° F Rise. 122k Effective BTU/h.
Item#: 32018
Model#: NR662OD-NG
Brand: Noritz
$899.56
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EnergyStar Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 9.3 GPM at 40° F Rise, 7.4 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.3 GPM at 70° F Rise. 184k Effective BTU/h.
Item#: 59266
Model#: NRC111-DV-LP
Brand: Noritz
$1,779.86
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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, 6.3 GPM at 60° F Rise, 5.4 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 61568
Model#: ATI-540H-P
Brand: A.O. Smith
$1,394.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 8.0 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.7 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 171k Effective BTU/h.
Item#: 61570
Model#: ATI-340H-N
Brand: A.O. Smith
$1,142.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.0 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 152k Effective BTU/h.
Item#: 61572
Model#: ATI-240H-N
Brand: A.O. Smith
$1,022.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 5.4 GPM at 40° F Rise, 4.4 GPM at 50° F Rise, 3.8 GPM at 60° F Rise, 3.2 GPM at 70° F Rise. 112k Effective BTU/h.
Item#: 61575
Model#: ATI-140H-N
Brand: A.O. Smith
$845.00
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EnergyStar Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 5.8 GPM at 40° F Rise, 4.5 GPM at 50° F Rise, 3.9 GPM at 60° F Rise, 3.3 GPM at 70° F Rise. 140k Effective BTU/h.
Item#: 69978
Model#: ATI-110U-N
Brand: A.O. Smith
$845.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 5.4 GPM at 40° F Rise, 4.4 GPM at 50° F Rise, 3.8 GPM at 60° F Rise, 3.2 GPM at 70° F Rise. 112k Effective BTU/h.
Item#: 69979
Model#: ATI-140H-P
Brand: A.O. Smith
$845.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.0 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 152k Effective BTU/h.
Item#: 69980
Model#: ATI-240H-P
Brand: A.O. Smith
$1,022.00
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$981.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 8.0 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.7 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 171k Effective BTU/h.
Item#: 69983
Model#: ATI-340H-P
Brand: A.O. Smith
$1,142.00
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$1,160.00
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EnergyStar Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 8.3 GPM at 40° F Rise, 6.9 GPM at 50° F Rise, 5.5 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 199k Max BTU/h.
Item#: 69986
Model#: ATI-510U-N
Brand: A.O. Smith
$1,059.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 5.4 GPM at 40° F Rise, 4.4 GPM at 50° F Rise, 3.8 GPM at 60° F Rise, 3.2 GPM at 70° F Rise. 112k Effective BTU/h.
Item#: 69991
Model#: ATO-140H-N
Brand: A.O. Smith
$845.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 5.4 GPM at 40° F Rise, 4.4 GPM at 50° F Rise, 3.8 GPM at 60° F Rise, 3.2 GPM at 70° F Rise. 112k Effective BTU/h.
Item#: 69992
Model#: ATO-140H-P
Brand: A.O. Smith
$845.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 6.7 GPM at 40° F Rise, 6.1 GPM at 50° F Rise, 5.0 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 171k Effective BTU/h.
Item#: 69994
Model#: ATO-240H-P
Brand: A.O. Smith
Originally $1,324.36$1,022.00
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EnergyStar Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 7.9 GPM at 40° F Rise, 6.2 GPM at 50° F Rise, 5.3 GPM at 60° F Rise, 4.5 GPM at 70° F Rise. 190k Max BTU/h.
Item#: 69996
Model#: ATO-310U-N
Brand: A.O. Smith
$849.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 8.0 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.7 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 171k Effective BTU/h.
Item#: 69998
Model#: ATO-340H-N
Brand: A.O. Smith
Originally $1,479.80$1,142.00
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 8.0 GPM at 40° F Rise, 6.8 GPM at 50° F Rise, 5.7 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 171k Effective BTU/h.
Item#: 69999
Model#: ATO-340H-P
Brand: A.O. Smith
Originally $1,479.80$1,142.00
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Ratings: 3.4 GPM at 40°F Rise, 2.7 GPM at 50°F Rise, 2 GPM at 70°F Rise
Item#: 70334
Model#: ED020480T2T
Brand: Eemax
$1,590.89
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Ratings: 1.4 GPM at 40°F Rise, 1.1 GPM at 50°F Rise, 0.8 GPM at 70°F Rise
Item#: 70352
Model#: HA008240
Brand: Eemax
$229.00
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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.