Tankless Water Heaters

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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#: 157489
Brand: A.O. Smith
Originally $1,453.00$1,089.75
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EnergyStar Condensing Water Heater. Ultra-Low NOx Emissions (14 ng/J or 20 PPM). Ratings: 7.5 GPM at 40° F Rise, 6 GPM at 50° F Rise, 5.1 GPM at 60° F Rise, 4.3 GPM at 70° F Rise. 160k BTU/h.
Item#: 160186
Model#: STHR-160M
Brand: State Water Heaters
$1,643.94
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EnergyStar Condensing Water Heater. Ultra-Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: 5.8 GPM at 40° F Rise, 3.9 GPM at 50° F Rise, 3.9 GPM at 60° F Rise, 3.3 GPM at 70° F Rise. 140k Effective BTU/h.
Item#: 70562
Model#: TK-110U-I-N
Brand: Takagi
$695.95
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). 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#: 70563
Model#: TK-310U-E-N
Brand: Takagi
$885.95
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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#: 123228
Model#: ATO-540HX3-N
Brand: A.O. Smith
Sale: $1,358.00
On Sale Through 10/31
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EnergyStar Commercial Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 9.3 GPM at 40& deg; F Rise, 7.4 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.3 GPM at 70° F Rise. 199k Effective BTU/h.
Item#: 82339
Model#: NCC199CDV-LP
Brand: Noritz
$2,472.00
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Commercial Water Heater. Low NOx Emissions (< 40 ng/J or 55 PPM). Ratings: GPM at 40° F Rise, GPM at 50° F Rise, GPM at 60° F Rise, 8.9 GPM at 70° F Rise. 304k Effective BTU/h.
Item#: 31838
Brand: Noritz
$4,887.00
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EnergyStar Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 8.4 GPM at 40° F Rise, 6.7 GPM at 50° F Rise, 5.6 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 180k Effective BTU/h.
Item#: 31860
Model#: NRC98-DV-NG
Brand: Noritz
$1,549.88
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EnergyStar Condensing Water Heater. Low NOx Emissions (< 40 ng/J or 55 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. 189k Effective BTU/h.
Item#: 61569
Model#: ATO-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: 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. 189k Effective BTU/h.
Item#: 70002
Model#: ATO-540H-N
Brand: A.O. Smith
$1,269.00
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EnergyStar Condensing Water Heater. Ultra-Low NOx Emissions (< 40 ng/J or 55 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 Effective BTU/h.
Item#: 70551
Model#: T-H3-DV-N
Brand: Takagi
$1,200.95
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EnergyStar Non-Condensing Water Heater. Ultra Low Nox Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 8.4 GPM at 40° F Rise, 6.7 GPM at 50° F Rise, 5.6 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 199k Effective BTU/h.
Item#: 59261
Model#: NR98-SV-NG
Brand: Noritz
$1,444.96
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EnergyStar Non-Condensing Water Heater. Ultra Low Nox Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 8.4 GPM at 40° F Rise, 6.7 GPM at 50° F Rise, 5.6 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 199k Effective BTU/h.
Item#: 59260
Model#: NR98-OD-NG
Brand: Noritz
$1,530.00
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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#: 59262
Model#: NRC111-DV-NG
Brand: Noritz
$1,779.86
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$365.99
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EnergyStar Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 5.5 GPM at 40° F Rise, 4.4 GPM at 50° F Rise, 3.7 GPM at 60° F Rise, 3.2 GPM at 70° F Rise. 120k Effective BTU/h.
Item#: 70845
Model#: EZTR40NG
Brand: Noritz
$1,542.41
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EnergyStar Condensing Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 10.0 GPM at 40
Item#: 73647
Model#: T9800 SE 199
Brand: Bosch Thermotechnology
$1,813.00
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Sale: $1,118.70
On Sale Through 10/31
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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#: 123210
Model#: ATI-540HX3-N
Brand: A.O. Smith
Sale: $1,486.00
On Sale Through 10/31
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Wall Mounted, Condensing Boiler Water Heater Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 9.8 GPM at 40° F Rise, 7.8 GPM at 50° F Rise, 6.4 GPM at 60° F Rise, 5.4 GPM at 70° F Rise. 199 k Effective BTU/h.
Item#: 154039
Model#: RXP199IN
Brand: Rinnai
$1,866.90
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Wall Mounted, Condensing Boiler Water Heater Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 9.8 GPM at 40° F Rise, 7.8 GPM at 50° F Rise, 6.4 GPM at 60° F Rise, 5.4 GPM at 70° F Rise. 199 k Effective BTU/h.
Item#: 154045
Model#: CXP199IN
Brand: Rinnai
$2,011.80
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Wall Mounted, Condensing Boiler Water Heater Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 9.8 GPM at 40° F Rise, 7.8 GPM at 50° F Rise, 6.4 GPM at 60° F Rise, 5.4 GPM at 70° F Rise. 199 k Effective BTU/h.
Item#: 154047
Model#: CX199IN
Brand: Rinnai
$1,582.70
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EnergyStar Non-Condensing Water Heater. Ultra Low Nox Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 8.4 GPM at 40° F Rise, 6.7 GPM at 50° F Rise, 5.6 GPM at 60° F Rise, 4.8 GPM at 70° F Rise. 199k Effective BTU/h.
Item#: 59265
Model#: NR98-SV-LP
Brand: Noritz
$1,444.96
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EnergyStar Condensing Water Heater. Ultra-Low NOx (14 ng/J or 20 ppm). 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#: 70564
Model#: TK-310U-I-N
Brand: Takagi
$910.95
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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.