background image

Commercial Gas Water Heaters

®

AOSCG10500

Revised April 2012

PG 1 OF 4

MasterFit

®

 Low NOx Commercial Gas Tank-Type 

Water Heaters

FEATURES

Eighty plus percentage thermal efficiency affords lower operating costs on 
most models.

INDUCED DRAFT BUILT-IN BLOWER

 - The blower is built into the top cover, factory 

mounted and wired.  Ideal for installations where negative pressure is present in the building. 
Blower proves draft prior to ignition. No drafthood or barometric damper required.

METAL VENTING

 - Rated Category I Appliance. Uses standard metal single wall or double 

wall type “B” vent. Can be commonly vented with other Category I appliances. Vent connects 
directly to the blower outlet. Perfect choice for retrofit and upgrade installations.

WATER CONNECTIONS

 - For ease of installation, all BTNs feature water connections on the 

top, front, and rear.

GLASSLINED TANK

 - Permaglas® Ultracoat is the proprietary ceramic coating developed 

by A. O. Smith’s ceramic engineers specifically for the heater. It is applied after the complete 
tank has been assembled to give a seamless barrier against hot water corrosion. The maximum 
working pressure is 160 psi.

INSTALLED COST SAVINGS

 - When multiple BTN units are exclusively used in a vent 

manifold, use the National Fuel Gas Code Table 13 Fan Sizing Charts to determine vent 
diameter and specifications. The BTN with its internal induced draft blower enables safe use of 
smaller vent diameters. This feature can save hundreds of dollars in installation costs.

FULLY AUTOMATIC DIGITAL CONTROLS WITH SAFETY SHUTOFF

 - Accurate, 

dependable control system. Manual reset gas shutoff device for added safety. Maximum inlet 
gas pressure is 14” W.C. Minimum gas pressure is 5.2” W.C. Natural Gas.

FOAM INSULATION

 - Saves fuel, helps reduce standby heat loss.

JACKET

- Heavy gauge steel finished with a baked enamel finish over a bonderized undercoat.

EASY CLEANING

 - Handhole cleanout allows access for easy cleaning.

FULLY TESTED FOR SAFETY AND PERFORMANCE

 - Design certified by the 

Underwriters Laboratory for 180°F hot water service. Meets rigid requirements of the National 
Sanitation Foundation when equipped with optional leg kit. Certified for use on combustible 
flooring.

INTERMITTENT IGNITION DEVICE

 - Eliminates standing pilot. Provides flame failure 

response in less than one second. Power ON/OFF switch.

EASY-TO-INSTALL

 

- Completely factory-assembled. Only gas, water, vent and electric 

connections need be made. Provided with drain valve.

ANODES

 - CoreGard™ long-life, stainless steel core anode rods.

PLUG KITS

 - Pipe nipples and caps are included to plug unused water connections.

APPROVAL RATINGS AND CERTIFICATION

 

- All models meet ANSI Z21.10.3 - CSA 4.3 

standards and the thermal efficiency and standby loss requirements of the U.S. Department 
of Energy and current edition of ASHRAE/IESNA 90.1. Models also comply with California 
Energy Commission (CEC) and Texas low NOx and Air Quality Management Districts with
requirements of less than 40 ng/j.

MODELS 

BTN 

120-400(A)

on selected models.

Approved to NSF Standard 5 
with option leg kit.

Low Lead Content

Reviews: