AT-P Brochure

© June 2017 A. O. Smith Corporation. All Rights Reserved
www.hotwater.com | 800-527-1953 Toll-Free USA | A. O. Smith Corporation | 500 Tennessee Waltz Parkway | Ashland City, TN 37015
COMMERCIAL-GRADE
RESIDENTIAL GAS WATER HEATERS
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AOSRG47107
For technical information call 800-527-1953. A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.
SUGGESTED SPECIFICATION FOR ATI-540P OR ATO-540P
The fully modulating, on-demand, condensing gas fired tankless water heater(s) with integrated recirculation pump shall be A. O. Smith Tankless
Water Heater model ATI-540P or ATO-540P, having a maximum input rating of 199,000 Btu/h and available in NG or LP. The heater shall have
¾ in. male NPT water and gas connections. The inlet gas supply pressures shall be 4.0 in. WC (min.) up to 10.5 in. WC (max.) for NG and 8.0
in. WC (min.) up to 14 in. WC (max.) for LP. The indoor heater(s) shall incorporate an integrated temperature controller that will provide pump
control, diagnostic information, fault history, and heater set temperature. The outdoor heater shall be factory supplied with a temperature
remote, 100276687, that can be installed up to 400 ft. from the heater using 20 gauge (minimum) control wire. The temperature remote shall
provide pump control, diagnostic information, fault history, and heater set temperature. The heater shall operate using 120 V / 60 Hz power
source. The indoor heater will incorporate a factory installed power cord.
The indoor heater shall be vented with 3” or 4” diameter schedule 40 PVC (solid core), CPVC, ABS, polypropylene or category IV vent pipe with
a length not to exceed 70 ft. (equivalent) for 3” vent or 100 ft. (equivalent) for 4” vent, terminating horizontally or vertically. The intake pipe
may use material such as PVC, (solid core) CPVC, ABS, aluminum, or Category IV pipe and cannot exceed 70 ft. (equivalent) for 3” vent or 100 ft.
(equivalent) for 4” vent. The indoor heater shall be able to be common vented with schedule 40 PVC (solid core) pipe or approved polypropylene
vent with a length not to exceed 100 ft. (equivalent) using up to 10 in. pipe. Proper sizing is provided in the heater’s installation manual. The
outdoor heater(s) shall be constructed with an integral exhaust vent on the front of the heater.
The water heater shall use a commercial grade copper alloy, fin tube primary heat exchanger with quick release brass or bronze waterways.
The secondary heat exchanger shall be constructed from stainless steel 316L. The heater shall be controlled by an onboard solid-state printed
circuit board which uses the following factory installed components: thermistors to monitor inlet & outlet water temperature and exhaust
temperature; a flow sensor to measure flow rate; a flame sensor to monitor combustion; an air-fuel ratio rod to measure and adjust operation in
order to maintain optimal combustion efficiency. The heater also consists of inline fusing and surge absorbers for electrical surge protection, an
electronic spark igniter, aluminized stainless steel burners, hi-limit temperature switches to monitor water and exhaust temperatures, modulating
gas valve, an overheat cutoff fuse and ceramic heating blocks to protect the heat exchanger and water piping from freezing. The indoor heater
shall incorporate auto-fire system and a pump circulation operation for additional freeze protection. The indoor model shall include an exhaust
temperature monitoring system using an exhaust thermistor and automatic hi-limit switch to maintain safe exhaust temperatures for sch. 40
PVC. The heater shall have a built-in condensate trap for the secondary heat exchanger.
The heater can manifold into an Easy-Link to provide additional capacity. The Easy-Link controls shall be built onto the onboard solid-state
printed circuit board and does not require external controls. The linking control wire shall be supplied with the heater.
The heater shall be design certified by CSA according to ANSI Z21.10.3 • CSA 4.3, approved for sale in the United States, ENERGY STAR
®
qualified, has a minimum uniform energy factor of 0.93, meets the energy efficiency requirements of the U. S. Department of Energy and
ASHRAE 90.1 and complies with SCAQMD Rule 1146.2 and other air quality districts with similar requirements for low NOx emissions of
14 ng/J or 20 ppm.