Bradford White VR-150-(kW) Manual

INSTALLATION AND SERVICE MANUAL
Electric Power Water Heater
12kW – 162kW
NOTE: retain this manual for future reference
Installation and service must be performed by Qualified Service Personnel Only.
WARRANTY:
Factory warranty (available on web site) does not
apply to units improperly installed or improperly operated.
Experience has shown that improper installation
or system design, rather than faulty equipment, is the cause of
most operating problems.
Excessive water hardness causing a lime/scale
build-up in the heater and/or on the immersion heating
elements is not the fault of the equipment
and is not covered under the manufacturer's warranty. (See Water
Treatment and Water
Chemistry)
Do not energize electrical system before heater is completely filled with water. Damage caused to the
immersion heating elements by dry fire is not covered under the manufacturer's warranty.
Follow start up
procedure in the manual. Water heater corrosion and component failure
caused by air-borne chemical vapors
is not covered under the manufacturer's warranty.
Corrosion damage caused by current leakage due to
improper grounding of electrical systems or
electronic components to the storage tank and related piping
is not covered by the
manufacturer's warranty. Under no circumstance will the manufacturer be liable for
consequential
damages resulting from the installation or use of this equipment. Correct installation procedures
and local codes must be adhered to.
SPECIAL INSTRUCTIONS TO OWNER:
WARNING:
Improper Installation,Adjustment, Alteration, ServiceorMaintenance can cause injury or
property damage. Refer to this manual. For assistance or additional information consult a qualified
installer, service agency or the electric utility
CHECKING EQUIPMENT:
This manual supplies information for the installation, operation and servicing of the appliance. It is strongly
recommended that this
manual be reviewed completely before proceeding with an installation. Upon receiving
equipment, check for signs of shipping damage. Pay particular attention to parts accompanying the water heater,
which may show signs of being
hit or otherwise being mishandled. Verify total number of pieces shown on
packing slip with
those actually received. Incase there is damage or a shortage, immediately notify carrier.
DO NOT USETHIS APPLIANCE IF ANYPART HAS BEEN UNDER WATER. THE POSSIBLE
DAMAGE TO A FLOODED APPLIANCE CAN BE EXTENSIVE AND PRESENT NUMEROUS
SAFETY HAZARDS. ANY APPLIANCE THAT HASBEENUNDERWATERMUSTBE REPLACED.
2

WARNING A
If the information in this manual is not followed exactly, a fire or explosion may result
causing property damage, personal injury or loss of life. Do not store or use gasoline or
other flammable vapors and liquids in the vicinity of this or any other appliance.
3

CONTENTS
Warranty 1
Safety Warnings 1
Checking the Equipment 1
Codes 4
Installation Requirements
Location 4
Drain Pan Requirements 5
Clearances 6
Mounting 7
Water Connections 7
Tank Construction 8
ReliefValve 8
Thermal Expansion 8
Cathodic Protection 9
Electrical Service
Electrical Connection 9
Wire Sizing 9
Fusing 9
Electrical Connection 9
Jacket Assembly 10
Standard and Optional Controls 10
Components and Controls
Terminal Block 11
Fuses and Fuse Blocks 12
Contactors 12
Transformer 12
Immersion Thermostat 13
Temperature Regulation 13
Risk of Scald Warnings 14
Temperature Control Sequencer .14
Display 16
Temperature Adjustment 17
Error Messages 18
Temperature Limit Control 18
Immersion Heating Elements 19
Safety Door Lock 19
Low Water Cut-Off.......................20
Low Water Pressure Switch .........20
High Water Pressure Switch 20
Manual Limiting Switches 20
Time Clock 21
Pilot Lights 21
Alarm Bell....................................21
Start-Up Procedure
Filling the Water Heater...............22
Start-Up Checks ...........................23
Shutdown Procedure.....................24
Maintenance
T&P Relief Valve ........................... 24
Water Chemistry...........................25
Flushing the Tank .........................25
Sediment Removal........................25
Scale Removal - Elements ...........25
Trouble Shooting
Not Enough Hot Water.................27
Water Is Too Hot...........................27
Water Heater Sounds....................27
Leakage 27
4

OWNER WARNING:
The information contained in this manual is intended for use by qualified professional installers, service
technicians or the electric utility. Consult your local expert for proper installation or service procedures.
IMPORTANT:
Consult and follow local Electrical Codes, Building and Fire Regulations and other Safety Codes that apply
to this installation. Consult local codes officials and electric utility company to authorize and inspect all field
installed electrical connections.
CAUTION:
Be sure to turn off power when working on or near the electrical system of the water heater. Never touch
electrical components with wet hands or when standing in water. When replacing fuses, always use the
correct size for the circuit. Do not test electrical system before the water heater is completely filled with
water. Follow the start-up procedure.
5

WARNING
To minimize the possibility of serious personal injury, fire or damage to your appliance, never violate
the following safety rules:
1. Always keep the area around your appliance free of combustible material, gasoline and other
flammable liquids and vapors.
2. Never cover your appliance, lean anything against it, store trash or debris near it, stand on it or any
way block the access to your appliance.
CODES:
The equipment shall be installed in accordance with those installation regulations in force in the local area
where the installation is to be made.
These shall be carefully followed in all cases. Authorities having jurisdiction shall be consulted before
installations are made. In the absence of such requirements, the installation shall conform to the latest edition
of the National Electrical Code, NFPA 70. When the appliance is installed in Canada, it must conform to the
CAE C22.1, Canadian Electrical Code, Part 1 and/or local Electrical Codes.
APPROVALS:
This complete appliance is design certified and Listed by Underwriters Laboratories as a commercial
storage electric water heater. This water heater bears the UL certification for the United States as tested
under the Standard for
Electric Booster and Commercial Storage Tank Water Heaters, UL1453 and C-UL
in Canada as testedundertheStandardforConstructionandTest of Electric Storage Tank Water Heaters,
CAN/CSA-C22.2 No. 110-M90. Allwaterheater storage tanks conform to the latest edition of the ASME
Boiler and Pressure Vessel Code, SectionIv.
INSTALLATION PROCEDURE LOCATION OF UNIT
1. Locate the appliance so that if water connections should leak, water damage will not occur. When
such locations cannot be avoided, it is recommended that
a suitable drain pan, adequately sized, be
installed under the unit. Under no
circumstances is the manufacturer to be held responsible for
water damage in
connection with this unit, or any of its components.
2. Insure that the appliance is located near
an acceptable drain so that the vessel can be properly drained
when performing
service or maintenance. The drain must also provide adequate drainage in the event
of leakage the tank or related
piping. The drain must prevent water damage to the adjacent area
and lower
floors of the structure.
3. The appliance must be installed so that the electrical components are protected from water (dripping,
spraying, etc.) during appliance operation and service (replacing of fuses, elements, etc.)
4. Appliances located in a garage or parking structure shall be installed so that the jacket and all piping
shall be located or protected so that it is not subject to physical damage by a moving vehicle.
5. The appliance must be installed on a level floor. Shim the base as necessary if leveling is required.
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6. The floor on which the appliance is installed must be capable of supporting the total weight of the
water heater when completely filled with water. Combustible floor locations may be used. Maintain
required clearances from combustible surfaces.
7. The appliance must not be installed on carpet.
8. The appliance must be installed indoors where it is protected from exposure to wind, rain and
weather.
9. Locate the appliance as close as possible to the point of major hot water usage, the water piping
and branch electrical circuit wiring.
10. Insulate water piping to control heat loss and possible condensation.
11. The appliance must be located in an area that is not subject to freezing. The ambient temperature
of the space where the appliance is installed must not go below 32° F (0° C) or above 104°F (40°
C).
CAUTION:
Installation of the water heater should be accomplished in such a manner that if the tank, piping or
any connections should leak, the flow of water will not cause damage to the structure. For this reason,
it is not advisable to install the water heater in an attic or upper floor. When such locations cannot be
avoided, a suitable drain pan must be installed under the water heater. Drain pans may be fabricated
or purchased from your plumbing wholesaler. The drain pan must be piped to an adequate drain.
Under no circumstances is the manufacturer to be held liable for any water damage in connection with
this water heater.
TABLE A – CLEARANCES FROM COMBUSTIBLE
CONSTRUCTION:
Right Side - 6” (15cm)
Rear 0”
Left Side Inspection Opening & Anode Rods
Front 36” (0.91m) for service to controls
and heating elements
Top 12” (30cm) for service access to
electrical service, water connections
and piping
Water Pipes 1” (25.4mm)
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Maintain minimum specified clearances for adequate operation. All installations must allow sufficient
space for servicing the electrical components, water pipe connections, piping and other auxiliary
equipment, as well as the appliance.
MOUNTING:
The water heater should be mounted to the floor following applicable architectural and local code
requirements or accepted standards for the specific site and model purchased. In areas prone to seismic
activity, it is recommended that the water heater be mounted to the floor according to recommended
procedures for the site. In some geographic areas, additional strapping or braces may be required, consult
local codes for specific requirements. Proper mounting will help to make the water heater less susceptible
to seismic damage.
WATER CONNECTIONS:
NOTE:
Before making any connections to the cold water inlet or hot
water outlet, insure that all piping is clean and free of material
or scale. This can usually be accomplished by "blowing out the
pipe." Any foreign material or scale entering the water heater
can adversely affect operation and performance.
NOTE:
When using copper tubing, solder tubing to an adapter before
attaching to the threaded nipple connection provided on the
water heater. Soldering directly to the threaded connection may
harm a lining in the nipple or damage the tank lining.
Inlet and out let connections
For ease of service, install dielectric unions on the cold water
inlet and hot water outlet of the water heater. The cold water
inlet connection is located on the lower right side of the water heater. A manual shutoff valve should be
installed upstream on the cold water source as an isolation device. The hot water outlet connection is located
on the top center of the water heater. A manual shutoff valve should be installed downstream on the hot
water outlet source as an isolation device in case the water heater must be disconnected from the system.
STORAGE TANK:
This appliance uses a glass lined steel tank to store the heated water for use. The storage tank is constructed
in accordance with the ASME Boiler and Pressure Vessel Code requirements, stamped and registered with
the National Board of Boiler and Pressure Vessel Inspectors. The tank is furnished with threaded
connections for cold water inlet, hot water outlet, a relief valve and a drain connection. The storage tank has
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hand hole for ease of inspection, cleanout and service. An optional manhole may be specified for a
greater ease of inspection. The interior of the storage tank is glass lined and fired insure a molecular
fusing of glass and steel to protect the steel base metal against corrosion. A magnesium anode(s) is standard
to enhance the protection of the substrate metal of the tank.
RELIEF VALVE:
This water heater is supplied with a temperature and pressure relief valve(s) sized in accordance with
ASME Boiler and Pressure Vessel Code, Section IV. Some water heaters may be supplied with an
optional pressure only relief valve. The relief valve(s) is installed in the vertical position and mounted in
the tapping provided in the storage tank. No valve is to be placed between the relief valve and the water
heater. To prevent water damage, the discharge from the relief valve must be piped to a suitable floor drain
for disposal when relief occurs. No reducing couplings or other restrictions shall be installed in the discharge
line. The discharge line shall allow complete drainage of the valve and line. Relief valves should be manually
operated at least once a year. A relief valve that fails to completely reseat and continues to discharge water
must be immediately replaced with a new, properly sized, temperature and pressure relief valve.
CAUTION:
Avoid contact with hot discharge water. Insure that no one is in front of or around the relief valve
discharge line. Make sure that the extremely hot water manually discharged from the relief valve will
not cause bodily injury or property damage.
THERMAL EXPANSION OF WATER:
A relief valve that discharges periodically may be due to thermal expansion in a closed system. A water
heater installed in a closed system, such as one with a backflow preventer or check valve an installed in the
cold water supply, shall be provided with means to control expansion. Contact the water supplier or local
plumbing inspector on how to correct this situation. DO NOT plug or cap the relief valve.
CATHODIC PROTECTION:
Hydrogen gas can be produced in a hot water system that has not been used for a long period of time
(generally two weeks or more). Hydrogen gas is extremely flammable. To prevent the possibility of injury
under these conditions, we recommend the hot water faucet be open for several minutes at a sink close to the
water heater before you use any electrical appliance which is connected to the hot water system. If hydrogen
is present, there will be an unusual sound such as air escaping through the pipe as the hot water begins to
flow. There should be no smoking or open flames near the faucet at the time it is open.
ELECTRICAL CONNECTIONS:
All installation procedures involving electric power connection should only be performed by a trained,
certified electrician. The appliance, when installed, must be electrically grounded in accordance with the
requirements of the authority having jurisdiction or in the absence of such requirements, with the latest
edition of the National Electrical Code, NFPA No. 70. When the appliance is installed in Canada, it
must conform to the CAE C22.l, Canadian Electrical Code, Part 1 and/or local Electrical Codes .
9

1. Use copper conductors only. All wiring between the appliance and field installed devices shall be
made with copper wire suitable for at least 75° C (167° F) temperature rating. If the wiring from an
old water heater installation was aluminum, replace the old wire with copper wire.
2. The factory internal wiring is attached to a terminal block inside the unit. The branch circuit is
connected to the terminal block through an opening provided on the top of the water heater electrical
access panel.
3. Line voltage wire exterior to the appliance must be enclosed in approved conduit or approved metal
clad cable.
4. To avoid serious damage, DO NOT energize the appliance until the system is full of water. Ensure
that all air is removed from the storage tank and piping before beginning initial operation. Operation
of a water heater without a completely filled tank may result in serious damage to the appliance and
heating element burn out.
5. The water heater should be connected with a separate grounded branch circuit with over current
protection and disconnect switch. The water heater should be grounded in accordance with national
and local codes. A ground terminal is provided for ground connection only.
6. Provide the appliance with proper overload protection in the branch circuit. It is suggested that the
electrician size the branch circuit at 125 percent of the heater ampere rating and further increase wire
size as necessary to compensate for voltage drop in long runs. Branch circuit voltage drop should not
exceed 3% at the heater.
7. Voltage applied to the heater should not vary more than +5% to -10% of the model and rating plate
marking for satisfactory operation.
8. A wiring diagram is provided with the water heater for the electricians use.
WARNING:
WATER HEATER IS EQUIPPED FOR OPERATION ON ONE VOLTAGE ONLY. Check the rating
plate label for the correct voltage and phase. DO NOT use this water heater with any other voltage other than
the voltage specified on the rating plate label. Failure to use the correct voltage can cause problems that can
result in death, serious bodily injury or property damage.
10

CAUTION:
DO NOT CONNECT THE WATER HEATER TO AN IMPROPER SOURCE OF ELECTRICITY!
CAUTION:
Never turn on the electric power or attempt to use this electric water heater unless it is completely
full of water. Water must flow from the hot water faucet before turning electrical power "ON."
Operation of a water heater without a completely filled tank may result in serious damage to the
appliance and heating element burn out.
JACKET ASSEMBLY:
Outer Jacket - The outer jacket assembly is constructed from steel, painted with enamel on both sides. This
coating process insures a long life from the jacket assembly.
STANDARD EQUIPMENT:
Your commercial electric water heater is equipped with the following as standard equipment:
•Low watt density immersion heating elements with an incoloy sheath.
•Internal fusing of all elements in a maximum of 48 amp increments provides additional safety. Fuse
cartridges are related at 1,000,000 amps interrupting capacity.
•A painted enamel steel outer jacket and electrical control panel are provided.
•Channel iron skid base.
•Electrical control panel is provided with a hinged door and key lock.
•A glass lined steel tank constructed to ASME specifications and provided with magnesium anode(s).
•ASME rated temperature and pressure relief valve provided by factory to insure safe heater operation.
•Terminal block connections are installed by the factory for safe easy wiring connection.
•Manual reset high water temperature limit control.
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•Immersion thermostat (one per 54kW of input as standard).
•180°F (82.2°C) temperature operation is possible to provide water for sanitizing applications.
•150 PSI
•Insulated to meet the latest edition of ASHRAE 90.1 energy efficiency standards.
•3 year limited warranty provides protection against failure of tanks due to defects in material and
workmanship.
•Underwriter's Laboratories, Inc. listing for all models as a commercial electric water heater.
OPTIONAL EQUIPMENT:
The following items are available as extra cost options:
•Electronic low water cut-off prevents energizing of the heater when it is not filled with water.
•Pilot lights - Monitor on-off cycle of contactors.
•Manual limiting switches with indicating lights to permit heater kW input to be manually limited as
desired.
•Temperature and pressure gauges are available installed flush with the jacket to monitor heater
performance.
•Electronic step controller module provides electronic thermostat control.
•Safety door interlock prevents opening of access door while heater is energized.
•Shunt trip disconnect provides power disconnect upon a control sensed malfunction.
•Alarm bell provides an audible alarm to warn of various control failures.
•Time clock to control off-on cycles of the heater as programmed by the owner or electric utility
requirements.
•Low water pressure switch.
•High water pressure switch.
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A main power terminal block isprovided for field connection of the branch power supply to the electric
water heater. All internal power circuits to the immersion heating elements are connected to the load side
of the main terminal block. The line side of the terminal block has individual lug type connections
properly sized for the recommended copper field wire size.
FUSE AND FLUE BLOCKS:
When appliance amperage exceeds 120Amps, each internal
power circuit is fused for safety. Each power circuit to an
immersion element is fused at a maximum of 48 amps. Power
circuits may be fused at lower current levels as needed to
balance current on three phase units. The power circuit fuses are
held by a spring loaded fuse block rated for the voltage specified
to operate the water heater.
The control circuit is also fused on both the primary and
secondary sides of the control circuit transformer.
CONTACTORS:
The power to the immersion electric heating elements
is switched by a definite purpose magnetic contactor.
The contactor is supplied with 120 VAC from the
control circuit when the immersion thermostat senses
a drop in stored water temperature below the desired
set point. A magnetic coil in the contactor is
energized to complete the electrical circuit supplying
power to the immersion heating elements. When the
thermostat is satisfied, the contactor coil is de-
energized and power to the heating elements is
turned off.
CONTROL CIRCUIT TRANSFORMER:
A transformer is used to reduce the line voltage to 120 VAC for
internal control operation. The transformer is fused on both the
primary and secondary side. The common side of the secondary
control circuit is grounded. The VA rating of the control circuit
transformer is based on the load of the various components in the
water heater control circuit.
13

WARNING:
HAZARD OF ELECTRICAL SHOCK - Before opening the electrical access panel to adjust the
thermostat or servicing the water heater, make sure the electrical supply to the water heater is turned "OFF".
Failure to do this could result in death, serious bodily injury or property damage.
IMMERSION THERMOSTAT (S):
This water heater uses an immersion thermostat(s) to activate magnetic contactors allowing current to flow to
the immersion heating elements. The standard control system uses one immersion thermostat for each 54kW
of electric heating power in a water heater. As an option, additional immersion thermostats may be provided
to add additional steps of thermostatic control. The sensing bulb for each immersion thermostat is immersed
in the stored water in the tank to provide quick, accurate response to changes in water temperature. The
thermostat sensing bulb is located near the elements it is controlling. The immersion thermostat set point is
adjustable by rotating a knob on the control. Turning the knob counter clockwise decreases the temperature
set point and turning the knob clockwise increases the set point. The temperature setting shown at the top of
the knob is the selected set point. The immersion thermostat has a fixed 6°F (3.3°C) differential.
TEMPERATURE REGULATION:
WARNING:
HAZARD OF ELECTRICAL SHOCK - Before opening the
electrical access panel to adjust the thermostat make sure the electrical
supply to the water heater is
turned "OFF".
DANGER:
Full power is present whenever the cabinet door is opened, even
with the pilot switch(es) turned off.
Set temperature control to the lowest setting which satisfies the hot water
requirements of the system. Lower water temperatures help minimize scale
formation on the heating elements. See thermostat information below for
electronic step control module.
WATER TEMPERATURE SETTINGS:
This water heater has an adjustable thermostat to control water temperature. The thermostat is factory pre-
set at approximately 125° F (51.7° C) or less. Households with small children or invalids may require a
120° F (48.9° C) or lower temperature setting to reduce risk of scald injury. Some states may require a
lower temperature setting. Check with your local codes or electric utility for local requirements governing
the temperature setting. Remember, no water heating system will provide exact temperatures at all times.
14

Allow a few days of operation at the setting to determine the correct temperature setting consistent with
your needs.
CAUTION:
Higher stored water temperature increases the ability of the heater to supply desired quantities of hot
water, however remember:
Hotter water increases the risk of scald injury. Setting the temperature selector dial higher provides
hotter water, which increases the risk of scald injury.
DANGER!!
WARNING:
WARNING: SHOULD OVERHEATING OCCUR OR THE TEMPERATURE CONTROLSFAILTO
SHUTOFF, TURNOFF
OR DISCONNECT THE ELECTRICAL SUPPLY AT THE MAIN
POWER DISCONNECT EXTERNAL TO THE APPLIANCE.
DANGER
• Water temperature over 125° F (51.7°C) can cause severe burns instantly or death from
scalding.
• Children, disabled and elderly are at highest risk of being scalded.
• See instruction manual before setting temperature at heating appliance.
• Feel water before bathing or showering.
• If this appliance is used to produce water that could scald if too hot, such as domestic hot
water use, adjust the outlet control (limit) or use temperature limiting valves to obtain a
maximum water temperature of 125° F (51.7° C).
Always close the electrical control panel door after making a temperature adjustment. Turn on
electricity
15

TEMPERATURE ADJUSTMENT:
1. Tum "OFF" the electrical power to the water heater. If the power disconnect point is out of sight, lock
it in the open ("OFF") position and tag to prevent unexpected application of power
2. Open the water heater's electrical access panel
3. Adjust each immersion thermostat to the desired temperature setting by turning the adjusting knob.
Each thermostat will be factory pre-set to approximately 125° F (51.7° C) or less as shipped
4. Close the water heater's electrical access panel.
5. Turn "ON" the electrical power to the water heater
CAUTION:
The maximum temperature set-point that should be set for the Immersion Thermostats or
programmed into the Electronic Temperature Step Control Module is 180° F (82° C).
ELECTRONIC TEMPERATURE STEP MODULE:
The water heater uses an optional adjustable electronic temperature
control to provide staged ON/OFF control of the electric heating
elements. Operation is based on temperature input from an immersion
temperature sensor. The sensor is a positive coefficient platinum
thermistor. The sensor is placed in a well located above the heating
elements it is controlling. A liquid crystal display is provided to indicate
sensed temperature and operating parameters. The temperature control
may operate in as many as four stages of control. For more stages of
operation, multiple electronic temperature control sequencers are installed
and wired to operate in series.
SPECIFICATIONS:
Set Point Adjustment Range: Max setting = 220˚ F (105˚ C).
Temperature Accuracy: +/- 1° F.
Display Resolution: 1° F via Liquid Crystal Display (LCD).
Sensor: Them1istor 4.8 ohms/˚F.
Operating Humidity: 5 - 95% RH Noncondensing.
Operating Ambient Temperature: -40° to 140° F.
16

HIGH WATER TEMPERATURE LIMIT CONTROL:
The unit is equipped with a fixed setting manual reset
high water temperature limit control. The water heater
temperature limit control has a fixed limit setting of 195°
F (90.6° C). If water temperature exceeds the limit set
point, the limit will break the control circuit and shut
down the unit. The limit control can only be reset after the
water temperature has cooled below the set point of the
limit. The high water temperature limit control is mounted
on the surface of the tank, above the heating element
installed at the highest point in the tank. The high limit
control is reset by pushing the red reset button on the
control. Operation of the limit control usually indicates a
major problem with the thermostat, contactors or heating
elements. Do not continue to push the reset multiple
times. The source of the problem
must be found and corrected to insure proper operation. The limit control is
covered with an
insulation blanket which must be removed to push the red reset button. The blanket of
insulation must be replaced before the power is
turned on and the water heater is returned to service.
CAUTION:
Disconnect the main power top the heater before opening the element access panel to reset the high
limit control.
NOTE:
The high limit control will not re-set until the water temperature has dropped below the set point of the high
limit.
IMMERSION HEATING ELEMENT: WARNING:
HAZARD OF ELECTRICAL SHOCK - Before openingthe accesspanel toremove or service
the immersion heating elements, make sure the electrical supply to the water heater is turned
"OFF". Failure to do this could result in death, serious bodily injury
or property damage.
The heating input to this commercial electric
water heater
is provided by low watt density immersion heating
elements. The heating elements are constructed from an
incoloy sheath with a tin plate on the exterior surface.
Three element blades are mounted on a single hex-head
screw-in mounting flange. The element flange mounts into
a 1 1/2" NPT threaded connection
welded to the storage
tank. The hex-head screw-
in mounting flange seals to the
tank with an "O"
ring gasket at the base of the threaded
portion of the flange. The tank flange has a matching recess
for the "O" ring gasket to insure a proper water tight seal.
17

The "O" ring element gasket must be replaced with a new gasket when an element is removed for inspection,
cleaning or replacement.
SAFETY DOOR INTERLOCK:
The optional safety door interlock is an electrically operated locking pawl that is energized when main power
to the water heater is turned "ON." The interlock is mounted to the inside of the electrical control panel door
and extends behind a locking flange when energized. Main power may be turned off and the electrical access
door may be opened for service.
With the door open, main power may be energized if required to service or troubleshoot the operation of
selected components.
DANGER:
HAZARD OF ELECTRICAL SHOCK - Full power is present whenever the cabinet door is opened
and main power is turned "ON" even with the pilot switch(es) turned off.
LOW WATER CUTOFF (OPTIONAL)
This water heater may be equipped with an optional electronic low water cut-off installed at the factory. This
low water cut-off device uses a water level sensing probe located above the heating element installed in the
highest point in the storage tank. If the internal water level drops below this point, the low water cut-off will
shut down operation of the heating elements. An electronic type low water cut-off is available as a factory
supplied option on all models. The optional electronic low water cut-off has an LED located on the main
circuit board. This LED will be illuminated and the control circuit will be completed between the common
and normally open contacts on the circuit board when the sensing probe is below the water level in the
storage tank. An optional manual reset function and test button is available on the electronic low water cut-
off. The operation of a low water cut-off should be inspected every six months.
LOW WATER PRESSURE SWITCH:
A low water pressure switch is available as an option on this water heater. A water pressure switch is used to
monitor the water pressure in the water heater storage tank. If the water pressure drops below an adjustable
set point, the control circuit is opened and operation of the water heater is shut down. The low water pressure
switch may be specified with either an auto-reset function or a manual reset function on low water pressure.
18

HIGH WATER PRESSURE SWITCH (OPTIONAL):
A high water pressure switch is available as an option on this water heater. A water pressure switch is used to
monitor the water pressure in the water heater storage tank. If the water pressure rises above an adjustable set
point, the control circuit is opened and operation of the water heater is shut down. The low water pressure
switch may be specified with either an auto-reset function or a manual reset function on high water pressure.
MANUAL LIMITING SWITCHES (OPTIONAL):
As an option, a switch or multiple switches may be provided to interrupt the 120 VAC control circuit feed
to the contactor coil or coils from the immersion heating thermostat(s). This switch may be used to
manually turn off a portion of the heating element input. This feature may be used to reduce electrical input
of the water heater in the summer months when ground water temperatures are warmer and full electrical
input from the immersion heating elements is not required. The water heater may be restored to full
input by moving the switches tothe "ON"position.
TIME CLOCK (OPTIONAL):
The water heater may be provided with an optional time clock. The time clock
will allow the water heater to be turned on and off with a pre-set schedule. The
time clock may be specified with a 24 hour scheduling period or with a 7 day
scheduling period. By the adjustment of the set points on the time clock, the
water heater may be turned off when hot water is not needed or in periods
when the building may not be occupied. The time clock allows the water
heater to automatically cycle on in advance of the time when hot water may be
needed. This will insure that hot water is always available yet save energy
when there are scheduled periods when there will be no requirement for hot
water. This feature is especially useful for schools and buildings that are
occupied on a fixed schedule. As an additional feature, time clocks may be
furnished with a spring wound carry-over function to insure that a switching schedule is maintained in
periods where there may be power interruptions. The time clock works by making and breaking the 120
VAC control circuit to the contactor coils to shut down operation of the heating elements in the desired time
periods.
PILOT LIGHTS (OPTIONAL):
The water heater may be provided with optional pilot lights to provide an external indicator for each
contactor or stage of heating elements that is energized. Each pilot light is wired in parallel with the 120
VAC control circuit feed to the contactor coil(s). The pilot will be turned on as the contactor coil(s) is
energized by the temperature controls.
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SHUNT TRIP DISCONNECT (OPTIONAL):
Shunt trip disconnect provides a power disconnect upon a control sensed malfunction via a circuit breaker
installed in the main power supply to the water heater. The circuit breaker is shipped as a separate item
that must be field installed. The water heater 120 VAC control circuit provides a feed to the circuit
breaker that will shut down main power on either a low water level condition (if equipped) or high water
temperature. Once the water heater is installed and all power is connected, the toggle switch that arms
the shunt trip must be placed in the on position to provide the shunt trip function on the desired control
sensed malfunction.
ALARM BELL (OPTIONAL):
An alarm bell with silencing switch is available as an option on this water heater.
The alarm bell can be used to provide an audible indication of a control sensed
malfunction. The user must specify the safety function or multiple safety
functions that the alarm bell will sound on when the water heater is ordered
from the factory. The
alarm bell typically is used to indicate a low water
condition or a high water temperature condition. The alarm is furnished with a
silencing switch to
turn off the audible alarm while trouble shooting a control
sensed malfunction that is indicated by an audible alarm. Once the control
sensed malfunction is corrected, the silencing switch must be returned to the
"ON" position to re-establish the audible alarm function.
START-UP PROCEDURES:
Never operate the heating elements without being certain the water heater is filled with water and a
temperature and pressure relief valve is installed in the relief valve opening on top of the heater.
The pilot switch(es) (if equipped) mounted on the control cabinet permit the heater to be turned on and off
without having to operate the electrical disconnect switch. The pilot switch interrupts only the 120 VAC
control circuit in the water heater. Full power is still present at the terminal block, fuses and contactors.
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DANGER:
Full power is present whenever the cabinet door is opened, even with the pilot switch(es) turned off.
THERMAL EXPANSION OF WATER:
A relief valve that discharges periodically may be due to thermal expansion in a closed system. Many water
systems are equipped with pressure reducing valves, check valves or back flow preventers which may cause
the water system to be closed. As water is heated it will expand in volume due to thermal expansion. The
system must make allowance for this expansion. If an expansion tank is not provided in the system, water
pressure may increase to the point where the water heater's temperature and pressure relief valve opens to
relieve the excess pressure. The temperature and pressure relief valve is not intended for the constant
relief of thermal expansion. This is an unacceptable condition and must be corrected. Do not plug or cap
the relief valve discharge! A properly sized expansion tank is typically installed in the potable water
system to relieve the pressure built up by thermal expansion of heated water. Consult your local plumbing
contractor and plumbing wholesaler for assistance in properly selecting an expansion tank for your
system.
As the water heater operates, there may be noises generated by the expansion and contraction of the metal
parts of the water heater and related piping. These noises may occur during periods of heat up or cool
down. They do not represent harmful or dangerous conditions.
1. FILLING THE WATER HEATER:
2. Insure that the electrical power to the water heater is in the "OFF" position.
If the power
disconnect point is out of sight, lock it in the open ("OFF") position and tag to prevent
unexpected application of power.
3. Close the water heater drain valve(s).
4. Open a nearby hot water faucet to allow the air in the system to escape as the tank fills.
5. Fully open the cold water inlet valve to the waterheater to beginfillingthe heaterand piping.
6. Check the nearby hot water faucet to verify that air is exiting the tank as it fills with water. Allow
water to run until a constant flow is obtained at the faucet. This will insure that all
air is purged
from the system.
NOTE: The cold water supply must be left in the open position when the water heater is in use.
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