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Gas Tankless Water Heaters
Gas Tankless Water Heaters
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Commercial/Residential (20)
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Dimensions
23-5/8 in H x 17-3/4 in W x 11-1/4 in D (6)
41.8 in H x 16.53 in W x 16.1 in D (3)
Energy Factor
0.82 (5)
0.95 (9)
0.9 (2)
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10 gpm (8)
6.6 gpm (8)
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10.5 gpm (3)
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1/2” NPT (1)
3/4 in NPT (21)
1/2 in NPT (2)
Heating Capacity
199000 Btu/hr (8)
180000 Btu/hr (5)
160000 Btu/hr (5)
190000 Btu/hr (4)
140000 Btu/hr (2)
120000 Btu/hr (2)
Height
20.75 in (3)
29.5 in (2)
33.25 in (7)
36.75 in (6)
28 in (5)
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Electronic (8)
Electronic Spark (18)
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Outdoor (3)
Indoor (20)
Indoor/Outdoor (3)
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150 psi (3)
15 to 150 psi (23)
Series
ATI-240HX3-N (1)
ATI-240HX3-P (1)
ATI-340HX3-N (1)
ATI-340HX3-P (1)
ATI-540HX3-N (1)
ATI-540HX3-P (1)
Ultra Low NOx
No (6)
Yes (17)
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3/4 in (6)
3 in, 4 in (9)
3 in, 5 in (2)
3 or 4 in (3)
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Power (6)
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Water Connection
3/4 in (3)
3/4 in NPT (17)
Width
12.375 in (5)
13.125 in (2)
15.625 in (7)
16.19 in (6)
22.25 in (3)
Height
20.75" (3)
28" (5)
29.5" (2)
33.25" (7)
36.75" (6)
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AO Smith®
AO Smith® 100227678 ATI-310C Tankless Water Heater, Natural Gas Fuel, 190000 Btu/hr Heating, Indoor, Non-Condensing, 8 gpm Flow Rate, Concentric Vent, 3 in, 5 in Vent, 0.82, Commercial/Residential
Part #
107307
MFG #
100227678
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AO Smith®
AO Smith® 100227685 ATI-510C Tankless Water Heater, Natural Gas Fuel, 199000 Btu/hr, Indoor, Non-Condensing, 10 gpm, 3 in, 5 in Concentric Vent, 0.82, Residential
Part #
107308
MFG #
100227685
Add to Cart
Compare
AO Smith®
AO Smith® 100227698 ATO-110U Tankless Water Heater, Natural Gas Fuel, 140000 Btu/hr Heating, Outdoor, Non-Condensing, 6.6 gpm Flow Rate, Direct/Power Vent, 0.81, Commercial/Residential
Part #
544429
MFG #
ATO-110-U
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AO Smith®
AO Smith® 100384228 ATM-160M-N Adapt™ SC Standard Condensing Ultra-Low NOx 160,000 BTU Natural Gas Tankless Water Heater
Part #
1283044
MFG #
100384228
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AO Smith®
AO Smith® 100384229 ATM-180M-N Adapt™ SC Standard Condensing Ultra-Low NOx 180,000 BTU Natural Gas Tankless Water Heater
Part #
1283053
MFG #
100384229
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AO Smith®
AO Smith® 100384230 ATM-199M-N Adapt™ SC Standard Condensing Ultra-Low NOx 199,000 BTU Natural Gas Tankless Water Heater
Part #
1283062
MFG #
100384230
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AO Smith®
AO Smith® Adapt™+ 100374800 ATHR-160X3 Tankless Water Heater, Natural Gas Fuel, 160000 Btu/hr Heating, Indoor/Outdoor, Condensing, 10.5 gpm Flow Rate, Direct/Power Vent, 0.95, Residential
Part #
1245415
MFG #
100374800
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AO Smith®
AO Smith® Adapt™+ 100374811 ATHR-180X3 Tankless Water Heater, Natural Gas Fuel, 180000 Btu/hr Heating, Indoor/Outdoor, Condensing, 10.5 gpm Flow Rate, Direct/Power Vent, 0.95, Residential
Part #
1245424
MFG #
100374811
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AO Smith®
AO Smith® Adapt™+ 100374812 ATHR-199X3 Tankless Water Heater, Natural Gas Fuel, 199000 Btu/hr Heating, Indoor/Outdoor, Condensing, 10.5 gpm Flow Rate, Direct/Power Vent, 0.95, Residential
Part #
1245433
MFG #
100374812
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AO Smith®
AO Smith® ProLine® 100123378 ATI-540H Tankless Water Heater, Natural Gas Fuel, 199000 Btu/hr Heating, Indoor, Condensing, 10 gpm Flow Rate, Direct/Power Vent, 3 in, 4 in Vent, 0.95, Commercial/Residential
Part #
101933
MFG #
100123378
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AO Smith®
AO Smith® 100227678 ATI-310C Tankless Water Heater, Natural Gas Fuel, 190000 Btu/hr Heating, Indoor, Non-Condensing, 8 gpm Flow Rate, Concentric Vent, 3 in, 5 in Vent, 0.82, Commercial/Residential
Part #
107307
MFG #
100227678
Add to Cart
Compare
AO Smith®
AO Smith® 100227685 ATI-510C Tankless Water Heater, Natural Gas Fuel, 199000 Btu/hr, Indoor, Non-Condensing, 10 gpm, 3 in, 5 in Concentric Vent, 0.82, Residential
Part #
107308
MFG #
100227685
Add to Cart
Compare
AO Smith®
AO Smith® 100227698 ATO-110U Tankless Water Heater, Natural Gas Fuel, 140000 Btu/hr Heating, Outdoor, Non-Condensing, 6.6 gpm Flow Rate, Direct/Power Vent, 0.81, Commercial/Residential
Part #
544429
MFG #
ATO-110-U
Add to Cart
Compare
AO Smith®
AO Smith® 100384228 ATM-160M-N Adapt™ SC Standard Condensing Ultra-Low NOx 160,000 BTU Natural Gas Tankless Water Heater
Part #
1283044
MFG #
100384228
Add to Cart
Compare
AO Smith®
AO Smith® 100384229 ATM-180M-N Adapt™ SC Standard Condensing Ultra-Low NOx 180,000 BTU Natural Gas Tankless Water Heater
Part #
1283053
MFG #
100384229
Add to Cart
Compare
AO Smith®
AO Smith® 100384230 ATM-199M-N Adapt™ SC Standard Condensing Ultra-Low NOx 199,000 BTU Natural Gas Tankless Water Heater
Part #
1283062
MFG #
100384230
Add to Cart
Compare
AO Smith®
AO Smith® Adapt™+ 100374800 ATHR-160X3 Tankless Water Heater, Natural Gas Fuel, 160000 Btu/hr Heating, Indoor/Outdoor, Condensing, 10.5 gpm Flow Rate, Direct/Power Vent, 0.95, Residential
Part #
1245415
MFG #
100374800
Add to Cart
Compare
AO Smith®
AO Smith® Adapt™+ 100374811 ATHR-180X3 Tankless Water Heater, Natural Gas Fuel, 180000 Btu/hr Heating, Indoor/Outdoor, Condensing, 10.5 gpm Flow Rate, Direct/Power Vent, 0.95, Residential
Part #
1245424
MFG #
100374811
Add to Cart
Compare
AO Smith®
AO Smith® Adapt™+ 100374812 ATHR-199X3 Tankless Water Heater, Natural Gas Fuel, 199000 Btu/hr Heating, Indoor/Outdoor, Condensing, 10.5 gpm Flow Rate, Direct/Power Vent, 0.95, Residential
Part #
1245433
MFG #
100374812
Add to Cart
Compare
AO Smith®
AO Smith® ProLine® 100123378 ATI-540H Tankless Water Heater, Natural Gas Fuel, 199000 Btu/hr Heating, Indoor, Condensing, 10 gpm Flow Rate, Direct/Power Vent, 3 in, 4 in Vent, 0.95, Commercial/Residential
Part #
101933
MFG #
100123378
Add to Cart
Sort by
Best Match
Product: A to Z
Product: Z to A
Product List View
List
Product Grid View
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