A.O. Smith CMC-SU-6, CMC-SU-54 User Manual

DURA-POWER

Commercial Electric Water Heaters

180°F BOOSTER MODELS

Dura-Power® commercial electric water heaters are designed to boost the water temperatures
for applications such as commercial dishwashers, which require very high temperature sanitizing
rinse—typically 180°F. Both 5-gallon countermount “CMC” models and 20-gallon “SU” models are
available with inputs up to 54 kW. Are models are also available with an optional stainless steel
tank for use with deionized water.

FEATURES

INCOLOY-SHEATH HEATING ELEMENTS STANDARD

Industrial-grade Incoloy sheathed heating elements are designed for rugged long-

lasting commercial service and can withstand sheath temperatures up to 1500°F

Each heating element has three separate heating loops, which provides more heating

surface, lower watt density and maximum recovery efficiency
Pre-wired leads provide excellent protection against oxidation and scaling
Input options from 6 kW to 54 kW, recoveries from 25 to 221 gallons per hour (gph)

at 100°F rise
Deionized models equipped with stainless steel standard elements

A. O. SMITH GOLDENROD ELEMENTS OPTIONAL

Patent-pending 24k gold-plated sheath plus medium watt-density ensures even

longer element life
Higher resistance to scale build-up, compared to Incoloy elements
Three-year warranty against failure due to lime scale build-up
Not available on deionized models

MODELS

CMC/SU-6

through

CMC/SU-54

STANDARD VOLTAGES FOR EASY INSTALLATION

Single-phase and three-phase
Single-phase 208V and 240V are field-convertible to three-phase
CMC models only, 208V and 240V at 24 kW and below are supplied as phase-convertible units

(single- to three-phase and vice versa)
277V single-phase also available – Contact A. O. Smith for 120V circuit availability

IMMERSION THERMOSTAT FOR EFFICIENT CONTROL

Close-differential, immersion-type thermostat for superbly accurate temperature control
Adjustable from 140°F to 185°F
Manual reset, high-temperature cutoff

HEAVY-DUTY MAGNETIC CONTACTORS

UL-rated 100,000 cycles

FACTORY-WIRED, 120V CIRCUIT CONTROLS

120V control circuit powered by fused transformer
Eliminates need for 120V service connection

(Optional)

Certified to NSF/ANSI 61

PG 1 OF 4

Revised October 2008

AOSCE15700

Commercial Electric Water Heaters

POWER-CIRCUIT FUSING FOR SYSTEM PROTECTION

Safeguards elements and contactors from short circuits, overloading and line surges
Required by National Electric Code and UL when current draw exceeds 120 A

ALL STAINLESS STEEL JACKET

Cleans easily, corrosion resistant, hinged for easy serviceability
Standard on CMC models, optional on SU models

GLASS-LINED TANK, ASME TANK CONSTRUCTION

Specifically developed for high-temperature water heater use
Provides long-lasting protection against corrosion
Equipped with anode rod for additional corrosion protection
Stainless steel tank on deionized models

MAXIMUM HYDROSTATIC WORKING PRESSURE: 150 PSI

FACTORY-INSTALLED TEMPERATURE & PRESSURE RELIEF VALVE MEETS ASHRAE/IESNA 90.1

THREE-YEAR LIMITED TANK WARRANTY

For complete information, consult written warranty or contact A. O. Smith

OTHER DURA-POWER CMC AND SU SERIES STANDARD FEATURES:

SIMPLIFIED, COLOR-CODED CIRCUITRY FOR EASE OF SERVICE

ASME T & P RELIEF VALVE

PRESSURE REDUCING VALVE WITH BYPASS CHECK AND STRAINER

TEMPERATURE/PRESSURE GAUGES

OTHER DURA-POWER CMC AND SU SERIES OPTIONS:

STAINLESS STEEL TANK

 • Fordeionizedwater

LOW-WATER CUTOFF

 • Probe-typeelectriclow-watercutoff
 • Preventsenergizingofelementswhenlow-waterconditionexists(automaticreset)

UNDERCOUNTER MOUNTING PAN FOR CMC MODELS

DUAL INDICATING/PILOT LIGHTS AND SWITCH

 • Lightsindicatewhenelementsareon,switchgivespositiveon-offcontrolofcontrolcircuit

SHOCK ABSORBER REDUCES WATER HAMMER

Revised October 2008 PG 2 OF 4

www.hotwater.com

AOSCE15700