A.O. Smith ACGSS02407, BTH-120, BTH-500 User Manual

BTH-120

through

UP TO 96% THERMAL EFFICIENCY,DIRECT VENT

The A.O. Smith Cyclone Xi family of products represents the industry’s most technologically
advanced commercial water heaters. The innovative Cyclone Xi design takes performance to
its highest level with efficiencies of 95% and 96%. Models are available from 120,000 BTUs
and now up to 500,000 BTUs. In addition, the Cyclone Xi features an Intelligent Control
System making it the smartest water heater in the industry.

Cyclone Xi provides outstanding hot water output, with dramatic savings on operating costs
compared to units with standard 80% efficiency. A.O. Smith’s leading-edge engineering
delivers conventional power-vent or sealed combustion power direct-vent versatility, low NOx
emissions and excellent space-saving characteristics. Powered anodes, standard on all
Cyclone Xi models, provide superior tank protection for years of trouble free operation.

INTELLIGENT CONTROL SYSTEM WITH LCD DISPLAY

• Exclusive A.O. Smith designed control

• Provides detailed water heater status information

• Precise temperature control

• Built-in diagnostics

• Run histrory information

SUBMERGED COMBUSTION CHAMBER,

WITH HELICAL HEAT EXCHANGER COIL

• Positioned in center of tank, surrounded by water to virtually
eliminate radiant heat loss from chamber

• Spiral heat exchanger keeps hot burner gases swirling, uses centrifugal
force to maximize efficiency of heat transfer to water in tank

• Spiral heat exchanger prevents scale and sediment from forming on
water-side surface, which can reduce energy efficiency over time

BTH-500

POWERED ANODES STANDARD ON ALL MODELS

• Provides long-lasting tank protection in varying water conditions

• Does not require maintenance or inspection

PERMAGLAS®ULTRA COAT™GLASS LINING

• Exclusive process provides superior protection against corrosion

• Both sides of heat exchanger coil are lined for protection against flue gas
condensate inside coil

MECHANICAL VENTING VERSATILITY

• Conventional power-venting or sealed combustion direct venting

• Vents vertically or through sidewall

• Direct-vent intake and exhaust pipe can terminate separately outside building,
or through single opening, using concentric vent assembly

• Uses inexpensive PVC, CPVC or ABS pipe for intake and exhaust

HIGH EFFICIENCY PRE-MIX POWERED BURNER

• Down-fired pre-mix burner provides optimum efficiency and quiet operation

• Top-mounted burner position prevents condensation from affecting burner operation

December 2007R

July 2007R

Rule 1146.2 Low NOx for

Approved,

California and Texas

BTH-120-250

BTH-300-500

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ACGSS02407

UP TO 96% THERMAL EFFICIENCY,DIRECT VENT

OTHER CYCLONE Xi FEATURES

SPACE-SAVING DESIGN FOR INSTALLATION FLEXIBILITY

• Reduced footprint, ease of service, protection from water damage in case of flooding

• Easy to remove top cover for convenient access to serviceable parts

• 0˝ installation clearances on sides and rear, 2˝ installation clearance on top, 4˝ alcove installation clearance in front
of unit

• 0˝ clearance to combustibles, approved for combustible floors

FACTORY-INSTALLED TEMPERATURE AND PRESSURE RELIEF VALVE
MAXIMUM HYDROSTATIC WORKING PRESSURE: 160 PSI
HANDHOLE CLEANOUT

• Allows easy access to tank interior for cleaning

CODES AND STANDARDS

•Design-certified by UL (Underwriters Laboratories) International, according to ANSZ21.10.3-CSA4.3 standards

governing storage-type water heaters

• Meets ASHRAE/IESNA 90.1-1999• Design-certified by Underwriters Laboratories to NSF standard 5 for 180° F (62° C) water

• Meets SCAQMD Rule 1146.2 for low-NOx emissions

• ASME tank construction optional on 120 to 250 model sizes. ASME tank construction standard on 300,400 and 500 models

THREE-YEAR LIMITED TANK WARRANTY

• For complete warranty details, consult written warranty shipped with heater, or contact A. O. Smith

INSTALLATION CONSIDERATIONS

1. Condensate Drain – This is a fully condensing water heater and should be located near a drain to permit proper

disposal of condensate.

2. Vent Termination – Exhaust gases of this water heater are less than 140° F. In cold climates water vapor in flue

gases will condense into a cloud of vapor where the vent exits the building. This vapor can gradually discolor exterior
building surfaces. Vent termination should be located where this vapor cloud and potential discoloration are not a
concern. Locating vent termination 6˝ or more from the wall helps vapor from being trapped along a building’s face.
To avoid this problem, the vent can be terminated on the roof. Always locate vent termination above the maximum
snowline, and do not locate vent termination above a walkway.

3 Air Intake – In cold climates, air intake should be located at least three feet from the vent termination of the water

heater and any other appliance vents that dischar
freeze-over of the intake screen required to prevent foreign objects from entering the intake pipe. Air intake should be
located above the maximum snowline.

4. Blockage Sensors – The water heater is equipped with sensors to shut it down if blockage of vent or air intake occurs.

A light on the heater’s diagnostic panel will alert service technicians to this problem.

5. Noise – Vent terminal should be located away from bedroom windows or other areas where blower noise will be

objectionable. Avoid venting into corners or confined areas, which will amplify sound. Anchoring intake or vent pipe
to walls or ceilings can cause noise to be transmitted to living areas, and isolation mounts should be used where
anchoring is required.

6 Optional Concentric Vent Kit - Helps to minimize unsightly wall/r

BTH-120 - 300 vent kit p/n 9003910105
BTH-400 - 500 vent kit p/n 9006144005

ge moisture-laden air (such as clothes dryers). This will help prevent

oof penetrations.

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ACGSS02407