A.O. Smith 52 User manual

1
Instruction Manual
PRINTED 0917 100293658 2000548791 (Rev. A)
PLACE THESE INSTRUCTIONS ADJACENT TO HEATER AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.
COMMERCIAL ELECTRIC WATER HEATERS
(OPTIONAL)
Thank you for buying this energy efcient water
heater. We appreciate your confidence in our
products.
MODELS 52/80/120 SERIES 100
INSTALLATION - OPERATION - SERVICE
MAINTENANCE - LIMITED WARRANTY
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SAFE INSTALLATION, USE, AND SERVICE
The proper installation, use and servicing of this water heater is extremely important to your safety and the safety of others.
Many safety-related messages and instructions have been provided in this manual and on your own water heater to warn you
and others of a potential injury hazard. Read and obey all safety messages and instructions throughout this manual. It is very
important that the meaning of each safety message is understood by you and others who install, use, or service this water heater.
This is the safety alert symbol. It is used to alert you to potential personal injury hazards. Obey all safety messages that follow
testing, repair or servicing of appliances and equipment; that is experienced in such work; that is familiar with all precautions
required; and that has complied with all the requirements of the authority having jurisdiction.”
DANGER
WARNING
CAUTION
CAUTION
DANGER indicates an imminently
hazardous situation which, if not avoided,
will result in injury or death.
This is the safety alert symbol. It is used to alert you to
potential personal injury hazards. Obey all safety
messages that follow this symbol to avoid possible
injury or death.
WARNING indicates a potentially hazardous
situation which, if not avoided, could result
in injury or death.
CAUTION indicates a potentially hazardous
situation which, if not avoided, could result in
minor or moderate injury.
CAUTION used without the safety alert
symbol indicates a potentially hazardous
situation which, if not avoided, could result in
property damage.
All safety messages will generally tell you about the type of hazard, what can happen if you do not follow the safety
message, and how to avoid the risk of injury.
IMPORTANT DEFINITIONS
• Qualied Installer or Service Agency:
Installation and service of this water heater requires ability equivalent to that of a Qualied Agency (as dened by ANSI
below) in the eld involved. Installation skills such as plumbing, electrical supply are required in addition to electrical testing
skills when performing service.
• ANSI Z223.1 2006 Sec. 3.3.83:
“Qualied Agency” - “Any individual, rm, corporation or company that either in person or through a representative is
engaged in and is responsible for (a) the installation, testing or replacement of gas piping or (b) the connection, installation,
testing, repair or servicing of appliances and equipment; that is experienced in such work; that is familiar with all precautions
required; and that has complied with all the requirements of the authority having jurisdiction.”
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GENERAL SAFETY INFORMATION
PRECAUTIONS
DO NOT USE THIS WATER HEATER IF ANY PART HAS
BEEN EXPOSED TO FLOODING OR WATER DAMAGE.
Immediately call a qualied service technician to inspect the
water heater and to replace any part of the control system
which has been under water.
If the unit is exposed to the following, do not operate heater
until all corrective steps have been made by a qualied service
technician:
1. External re.
2. Damage.
3. Firing without water.
GROUNDING INSTRUCTIONS
This water heater must be grounded in accordance with the
National Electrical Code and/or local codes. These must
be followed in all cases. Failure to ground this water heater
properly may also cause erratic control system operation on
ELECTRONIC CONTROL models.
This water heater must be connected to a grounded metal,
permanent wiring system; or an equipment grounding
conductor must be run with the circuit conductors and
connected to the equipment grounding terminal or lead on
the water heater.
HYDROGEN GAS (FLAMMABLE)
Explosion Hazard
Flammable hydrogen gases
may be present.
Keep all ignition sources away
from faucet when turning on
hot water.
Hydrogen gas can be produced in a hot water system served
by this heater that has not been used for a long period of time
(generally two weeks or more). Hydrogen gas is extremely
ammable. To reduce the risk of injury under these conditions,
it is recommended that the hot water faucet be opened for
several minutes at the kitchen sink before using any electrical
appliance connected to the hot water system. If hydrogen is
present there will probably be an unusual sound such as air
escaping through the pipe as the water begins to ow. THERE
SHOULD BE NO SMOKING OR OPEN FLAME NEAR THE
FAUCET AT THE TIME IT IS OPEN.
Water temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the
physically or mentally disabled are at
highest risk for scald injury.
Feel water before bathing or
showering.
Temperature limiting devices such as
mixing valves must be installed
when required by codes and to
ensure safe temperatures at fixtures.
Improper installation, use and service may result
in property damage.
Do not operate water heater if exposed to flooding or
water damage.
•
Inspect anode rods regularly, replace if damaged.
•
Install in location with drainage.
•
Fill tank with water before operation.
•
Properly sized thermal expansion tanks are required on all
closed water systems.
•
Refer to this manual for installation and service.
CAUTION
Explosion Hazard
Overheated water can cause
water tank explosion.
Properly sized temperature and
pressure relief valve must be
installed in the opening provided.
Read and understand this instruction
manual and the safety messages
herein before installing, operating or
servicing this water heater.
Failure to follow these instructions and
safety messages could result in death
or serious injury.
This manual must remain with the
water heater.
Explosion Hazard
Flammable hydrogen gases
may be present.
Keep all ignition sources away
from faucet when turning on
hot water.
• Before removing any access panels
or servicing the water heater, make
sure the power supply to the water
heater is turned off.
• Failure to follow these instructions
and safety messages could result in
death or serious injury.
Electrical Shock Ha z ard
When servicing this unit, verify the power to the unit is turned off prior to opening the control cabinet door.
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TABLE OF CONTENTS
SAFE INSTALLATION, USE, AND SERVICE..................... 2
Important Denitions ......................................................2
GENERAL SAFETY INFORMATION.................................. 3
PRECAUTIONS .............................................................3
HYDROGEN GAS (FLAMMABLE).................................3
INTRODUCTION................................................................ 5
Preparing for the Installation ..........................................5
DIMENSIONS AND CAPACITIES DATA ............................ 6
APPROVALS ...................................................................... 7
MODEL AND RATING ........................................................ 7
FEATURES AND COMPONENTS ..................................... 8
LOCATING THE NEW WATER HEATER ......................... 10
Facts to Consider About the Location ...........................10
INSTALLATION .................................................................11
REQUIRED ABILITY .....................................................11
General..........................................................................11
CONTAMINATED WATER.............................................11
CIRCULATING PUMP...................................................11
INSULATION BLANKETS .............................................11
TEMPERATURE-PRESSURE RELIEF VALVE.............11
WATER LINE CONNECTIONS .....................................12
CLOSED WATER SYSTEMS........................................12
THERMAL EXPANSION................................................12
ELECTRICAL ................................................................... 13
GENERAL .....................................................................13
AMPERAGE TABLE/OVERCURRENT PROTECTION.14
HEATER CIRCUITS - ELECTRONIC CONTROL
MODELS .......................................................................14
CONTROL CIRCUIT - ELECTRONIC CONTROL
MODELS .......................................................................14
Sequence of Operation .................................................14
WIRING DIAGRAMS........................................................ 16
CONVERSION TO SINGLE PHASE .............................18
CONVERSION TO THREE PHASE ..............................18
CONVERSION TO SINGLE PHASE .............................20
CONVERSION TO THREE PHASE ..............................20
OPERATION..................................................................... 21
GENERAL .....................................................................21
FILLING THE WATER HEATER....................................21
INITIAL START UP ........................................................21
Draining the Water Heater.............................................21
TEMPERATURE REGULATION ...................................... 22
High Temperature Limit Controls (ECO)........................22
Thermostat Controls......................................................22
Thermostat Settings - Surface Mount Control ..............22
THERMOSTAT SETTINGS - electronic Controls .........23
ELECTRONIC CONTROL MODELS OPERATION.......... 24
CONTROL SYSTEM FEATURES .................................24
CONTROL SYSTEM NAVIGATION...............................24
THE DESKTOP SCREEN .............................................24
Temperatures Menu ......................................................26
TEMPERATURE SETTINGS.........................................27
HEATER STATUS MENU..............................................28
ECONOMY MODE SETUP MENU................................28
Economy Mode Settings ...............................................30
Economy Mode Settings ...............................................31
ALARM OUTPUT SETUP MENU..................................33
DISPLAY SETTINGS MENU.........................................33
HEATER INFORMATION MENU...................................33
CURRENT FAULT / ALERT MENU ...............................34
FAULT HISTORY MENU ...............................................34
FAULT OCCURRENCE MENU .....................................34
RESTORE FACTORY DEFAULTS MENU ....................35
MAINTENANCE ............................................................... 35
General..........................................................................35
Anode Rod Inspection ...................................................35
FLUSHING the Water Heater ........................................36
SEDIMENT REMOVAL..................................................36
LIME SCALE REMOVAL...............................................36
TROUBLESHOOTING CHECKLIST ................................ 37
CHECKLIST ..................................................................37
REPLACEMENT PARTS...............................................37
Leakage Checkpoints....................................................37
PIPING DIAGRAMS ......................................................... 39
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Thank You for purchasing this water heater. Properly installed
and maintained, it should give you years of trouble free service.
Abbreviations Found In This Instruction Manual:
• AHRI - Air Condition, Heating and Refrigeration Institute
• ANSI - American National Standards Institute
• ASME - American Society of Mechanical Engineers
• NEC - National Electrical Code
• NFPA - National Fire Protection Association
• UL - Underwriters Laboratory
PREPARING FOR THE INSTALLATION
1. Read the “General Safety Information” section of this
manual rst and then the entire manual carefully. If you don’t
follow the safety rules, the water heater may not operate
safely. It could cause DEATH, SERIOUS BODILY INJURY
AND/OR PROPERTY DAMAGE.
This manual contains instructions for the installation,
operation, and maintenance of the electric water heater.
It also contains warnings throughout the manual that you
must read and be aware of. All warnings and all instructions
are essential to the proper operation of the water heater
and your safety. READ THE ENTIRE MANUAL BEFORE
ATTEMPTING TO INSTALL OR OPERATE THE WATER
HEATER.
Detailed installation diagrams are in this manual. These
diagrams will serve to provide the installer with a reference
for the materials and method of piping suggested.
IT IS NECESSARY THAT ALL WATER PIPING AND
THE ELECTRICAL WIRING BE INSTALLED AND
CONNECTED AS SHOWN IN THE DIAGRAMS.
Particular attention should be given to the installation of
thermometers at the locations indicated in the diagrams
as these are necessary for checking the operation of the
heater.
Be sure to turn off power when working on or near the
electrical system of the heater. Never touch electrical
components with wet hands or when standing in
water. When replacing fuses always use the correct size
for the circuit. see page 13.
The principal components of the heater are identied
on pages 7 & 8. The model and rating plate on page 6
interprets certain markings into useful information. Both of
these references should be used to identify the heater, its
components and optional equipment.
2. The installation must conform with these instructions
and the local code authority having jurisdiction and the
requirements of the power company. In the absence of local
codes, the installation must comply with the current editions
of the National Electrical Code, NFPA 70 or the Canadian
Electrical Code CSA C22.1. The National Electrical Code
may be ordered from: National Fire Protection Association,
1 Batterymarch Park, Quincy, MA 02269. The Canadian
Electrical Code is available from the Canadian Standards
Association, 8501 East Pleasant Valley Road, Cleveland,
OH 44131.
3. If after reading this manual you have any questions or do
not understand any portion of the instructions, call the toll
free number listed on the back cover of this manual for
technical assistance.
A sample rating plate is shown on page 6 of this manual.
In order to expedite your request, please have full model
and serial number available for the technician.
4. Carefully plan your intended placement of the water heater.
Examine the location to ensure the water heater complies
with the “Locating the New Water Heater” section in this
manual.
Installation and service of this water heater requires ability
equivalent to that of a licensed tradesman or qualied
agency (page 2) in the eld involved. Plumbing and
electrical work are required.
INTRODUCTION
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DIMENSIONS AND CAPACITIES DATA
Table 1. Tank Capacities and Dimensions
Model Number Tank Capacity in Gallons (Liters) A - Inches (mm) B - Inches (mm) C - Inches (mm) Inlet/Outlet
52 50 (189.3) 55 3/4 (1416) 21 3/4 (552) 27 (685) 1 1/4
80 80 (302.8) 60 1/4 (1350) 25 1/2 (648) 31 (787) 1 1/4
120 119 (450.5) 62 1/4 (1581) 29 1/2 (749) 35 (889) 1 1/4
Table 2. Recovery Rate in Gallons Per Hour Temperature Rise °F
Standard
KW Input
BTU/
Hour 30° 40° 50° 60° 70° 80° 90° 100° 110° 120° 130° 140°
6 20,478 82 62 49 41 35 31 27 25 22 21 19 18
9 30,717 123 92 74 62 53 46 41 37 34 31 28 26
12 40,956 164 123 98 82 70 61 55 49 45 41 38 35
13.5 46,075 184 138 111 92 79 69 62 55 50 46 43 40
15 51,195 205 154 123 102 88 77 68 61 56 51 47 44
18 61,434 246 184 148 123 105 92 82 74 67 61 57 53
24 81,912 328 246 197 164 140 123 109 98 89 82 76 70
27 92,151 369 276 221 184 158 138 123 111 101 92 85 79
30 102,390 410 307 246 205 176 154 137 123 112 102 95 88
36 122,868 492 369 295 246 211 184 164 148 134 123 113 105
40.5 138,226 554 418 3332 277 237 208 1185 166 151 138 128 119
45 153,585 615 461 369 307 263 230 205 184 168 154 142 132
54 184,302 738 553 443 369 316 277 246 221 201 184 170 158
*Figured at 1 KW (3413 Btu) = 4.1 gallons at 100°F temperature rise.
To determine recovery rate per minute, divide recovery rate per hour by 60.
This Instruction Manual covers two models of commercial
electric water heaters:
These two models are equipped from the factory with different
controls.
In this Instruction Manual, one model is factory equipped with
a surface mounted thermostat/ECO combination control and is
referred to as a surface-mount control model.
The other model is equipped with an electronic control system
and is referred to as an electronic control model.
Figure 1. Dimensions and Components
3/4” NPT
OPENING
DISPLAY FOR
ELECTRONIC
CONTROL
MODELS ONLY
WATER
OUTLET
CONDUIT
OPENING
INLET
OPENING
DRAIN
VALVE
A
C
B
5.25
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APPROVALS
MODEL AND RATING
All models meet
National Sanitation
Foundation NSF-5
requirements.
LISTED
22U1
No. OF
WATTS
PHASE VOLTS - AC ELEMENTS EACH
RATED MEASURED
%
WATTS
COMMERCIAL STORAGE
TANK WATER HEATER
MODEL NUMBER SERIAL NUMBER ITEM ID / PART NUMBER
WATTS
TOTAL
CAPACITY US GAL STANDBY LOSS MAX WORKING
PRESSURE
Low Lead Content
All models are listed
by Underwriters
Laboratories Inc.
Low Lead Content
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FEATURES AND COMPONENTS
Figure 2. Electronic Control Modules
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FEATURES AND COMPONENTS
Figure 3. Surface Mount Control Models
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FACTS TO CONSIDER ABOUT THE LOCATION
Carefully choose a location for the new water heater. The
placement is a very important consideration for the safety of
the occupants in the building and for the most economical use
of the water heater.
Whether replacing an old water heater or putting the water
heater in a new location, the following critical points must be
observed. The water heater must be located:
• On a level surface. Shim the channel type skid base as
necessary if levelling is required.
LOCATING THE NEW WATER HEATER
• Near a oor drain. The heater should be located in an area
where leakage of the tank or connections will not result in
damage to the area adjacent to the heater or to lower oors
of the structure.
• Close to the point of major hot water usage and the power
supply.
• Hot water piping and branch circuit wiring should be as
short as possible.
• Insulate hot and cold water piping where heat loss and
condensation may be a problem.
• Heater construction permits installation, maintenance, and
service work to be performed through the front control panel.
• Suggested clearances from adjacent surfaces are 12 inches
on top, 30 inches in front for access to the unit.
• The heater may be installed on or against combustible
surfaces. The left side and back may be placed ush against
adjacent surfaces.
• The temperature of the space in which the water heater is
installed must not go below 32°F or above 122°F.
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