ESSENCY EXR User manual

N09040000B April 2022
WATER HEATER
EXR
Water is essential to life. And Essency brings
water to your life in amazing ways. We design
water heaters built to outlast other tanks. Water
heaters intelligent enough to give you greater
control and peace-of-mind. All while delivering
the highest performance in the industry in a
design that’s both aesthetically appealing and
ecologically attentive. Our water heaters turn
the essential into the exceptional.
Installation &
Operation Manual

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In this box, you will find :
1. Your Essency EXR water heater.
2. This Installation & Operation manual.
3. One bag containing:
• (3x) M4x20 metric screws,
Intended as spares should you lose some screws during installation.
• (4x) Flat gaskets ½’’,
• (6x) Flat gaskets ¾’’,
Intended as spares, should you wish to replace them during routine maintenance such as flushing.
• (1x) 4 pins terminal,
• (1x) 12 pins terminal,
These will be usefull when adding future options to the water heater.
EXR water heater Installation & Operation manual
Flat gasket ½'' Flat gasket ¾''
Options terminal 4 pinsM4x20 screw Options terminal 12 pins
x1 x4 x6
x1
x1x1x3

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PLEASE READ THIS MANUAL CAREFULLY AND KEEP IT WITH THE WATER
HEATER FOR FUTURE REFERENCE
This manual contains all basic directions and recommendations for the installer to ensure proper installation
and adjustment of the water heater. For the owner/operator, it includes the features, operation, safety
precautions, maintenance and troubleshooting of the water heater. It also includes information on Service
parts section (see page 46).
All persons who are expected to install, operate or adjust this water heater should read the instructions
carefully so they may understand how to perform these operations. We require that you contact a plumbing
professional for the installation of this water heater.
If you have any specific questions regarding the operation, maintenance, service or warranty of this water
heater please contact the seller from whom it was purchased. If additional information is required, refer to the
Troubleshooting & Service section page 43 of this manual.
CONGRATULATIONS!
By purchasing an Essency EXR Water Heater, you have chosen the
most innovative technology in domestic water heating on the market.
Once properly installed, you can relax and enjoy many years of
trouble-free service.
Thanks to their innovative design, Essency water heaters oer a much
longer life span than traditional water heaters, as well as superior
performance for optimal user comfort.
In the following pages you will find information about how to install
and how to operate your water heater, as well as useful tips on how to
reduce water and energy consumption.
RECOGNIZE THIS SYMBOL AS AN INDICATION OF IMPORTANT SAFETY INFORMATION

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SAFETY INFORMATION
General Information............................................................ 5
Important Safety Precautions ............................................. 7
Transportation & Storage (At Warehouse)....................... 9
Water Quality....................................................................... 9
INSTALLING THE WATER HEATER
Location and Specifics ....................................................... 10
1. Connecting the Battery ................................................. 13
2. Connecting the Water Supply ...................................... 14
2.1. Typical Installation .................................................... 14
2.2. Recirculation............................................................ 16
3. Electrical connection ..................................................... 18
4. Filling the Water Heater ............................................... 21
5. Connectivity................................................................... 22
OPERATING THE WATER HEATER
Safety Precautions............................................................. 24
General Principle of Operation........................................ 24
Software Updates .............................................................. 26
Touchscreen........................................................................ 27
Setting the Water Temperature ....................................... 30
Heating Modes.................................................................... 31
Temporary Functions......................................................... 32
Parameter Settings............................................................ 35
Occasional Refill of the Tank............................................ 39
Essency App....................................................................... 39
CARE AND CLEANING
Draining the Water Heater.............................................. 40
Flushing the Water Heater................................................ 41
Cleaning the Water Heater .............................................. 42
Routine Inspection............................................................. 42
TROUBLESHOOTING & SERVICE
Service Parts....................................................................... 46
Service Log ........................................................................ 47
Wiring Diagram .................................................................. 48
Warranty ............................................................................. 49
Notes................................................................................... 50
Tips for Water Conservation.............................................. 51
If You Need Help ................................................................ 51
TABLE OF CONTENTS

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SAFETY INFORMATION
GENERAL INFORMATION
This water heater’s design is certified by UL and listed in accordance with UL 174.
This water heater must be installed in accordance with local codes. In the absence of local codes, install this
water heater in accordance with the N.E.C. Reference Book (latest edition). The warranty for this water
heater is in eect only when the water heater is installed, adjusted, and operated in accordance with these
Installation and Operating Instructions. The manufacturer will not be held liable for damage resulting from
alteration and/or failure to comply with these instructions. This water heater has been designed and certified
for the purpose of heating potable water. The installation and use of this water heater for any purpose other
than the heating of potable water, may cause damage to the water heater and create a hazardous condition
and nullify the warranty. Do not use this appliance if any part has been submerged in water. The plumbing
professional responsible for the installation of this water heater should be contacted to inspect the appliance
and to replace any part of the control system, including thermostat, which has been submerged in water.
Make sure that the rating plate on the water heater is referenced for certainty that the correct voltage is
being supplied to the water heater.
IMPORTANT: Before proceeding, please inspect the water heater and its components for possible damage.
DO NOT install any damaged components. If damage is evident, please contact the supplier where the water
heater was purchased or the manufacturer listed on the rating plate for replacement parts.
FOR YOUR RECORDS
Write the model and serial numbers here:
The model and serial number can be found on the
identification label, located on top of the water heater.
Model #:
Serial #:
Installing Company:
Installing Technician:
Contact Phone Number:
Staple sales receipt here.
Proof of the original purchase date is needed to
obtain service under the warranty.

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READ THIS MANUAL
This manual contains useful and important
information for proper installation and operation
of your water heater, as well as information and
recommendations for maintenance to ensure that
you will obtain the best performance and life span of
your Essency water heater.
At the end of the manual you will find a
Troubleshooting & Service section page 43 with
diagnostic codes, which will allow you to solve most
common problems.
Your water heater is FCC compliant.
Essency is not responsible for any changes or
modifications not expressly approved by the party
responsible for compliance. Such modifications
could void the user’s authority to operate the
equipment.
NOTE: This equipment has been tested and found
to comply with the limits for a Class B digital device,
pursuant to part 15 of the FCC Rules. These limits
are designed to provide reasonable protection
against harmful interference in a residential
installation. This equipment generates, uses, and can
radiate radio frequency energy and, if not installed
and used in accordance with the instructions, may
cause harmful interference to radio communications.
However, there is no guarantee that interference
will not occur in a particular installation. If this
equipment does cause harmful interference to radio
or television reception, which can be determined
by turning the equipment o and on, the user is
encouraged to try to correct the interference by one
or more of the following measures:
• Reorient or relocate the receiving antenna.
 Increase the separation between the equipment
and the receiver.
 Connect the equipment into an outlet on a
circuit dierent from that to which the receiver is
connected.
 Consult the dealer or an experienced radio/TV
technician for help.
This device must be professionally installed.
This equipment complies with FCC’s radiation
exposure limits set forth for an uncontrolled
environment under the following conditions :
This equipment should be installed and operated
such that a minimum separation distance of 20cm
is maintained between the radiator (antenna) and
user’s/nearby person’s body at all times.
This transmitter must not be co-located or operating
in conjunction with any other antenna or transmitter.
READ THE SAFETY INFORMATION
The following defined terms are used throughout
this manual to bring attention to the presence
of hazards of various risk levels or to important
product information. These words mean:
DANGER! An imminently hazardous situation
which, if not avoided, will result in death or serious
injury.
WARNING! A potentially hazardous situation
which, if not avoided, could result in death or
serious injury and/or damage to property.
CAUTION! A potentially hazardous situation
which, if not avoided, may result in minor or
moderate injury.
NOTICE: Attention is called to observe a specified
procedure or maintain a specific condition.

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IMPORTANT SAFETY INSTRUCTIONS
Read all instructions before using this water heater.
WATER TEMPERATURE SETTING
DANGER!
Safety and energy conservation are important factors to be considered when selecting the water
temperature setting of your water heater. Water temperatures above 125°F, and above 120°F for households
with small children, disabled, or elderly persons, can cause severe burns or death from scalding. Be sure
to read and follow the warnings outlined on the label pictured below. This label is also located on the water
heater near the touchscreen.
APPROXIMATE TIME/TEMPERATURE
RELATIONSHIP IN SCALDS
Temperature Time To Produce a Serious Burn
120°F More than 5 minutes
125°F 1½ to 2 minutes
130°F About 30 seconds
135°F About 10 seconds
140°F Less than 5 seconds
145°F Less than 3 seconds
150°F About 1½ seconds
155°F About 1 second
NOTICE: Mixing valves may be required by local
codes for reducing point of use water temperature
by mixing hot and cold water in branch water lines. If
required, a mixing valve complying with the Standard
for Temperature Actuated Mixing Valves for Hot
Water Distribution Systems, ASSE 1017 should
be installed. For more details contact a licensed
plumber or the local plumbing authority for further
information.
Water temperature over 125°F can cause severe
burns instantly or death from scalds. Children,
disabled and elderly are at highest risk of being
scalded. See instruction manual before setting
temperature at water heater. Feel water before
bathing or showering. Temperature limiting values
are available, please check with your installer.
NOTICE: Your water temperature setpoint is
125°F by default.

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IMPORTANT SAFETY INFORMATION
Read all instructions thoroughly before installing or operating.
WARNING!
This manual provides information on the installation, operation and maintenance of the water heater.
To reduce the risk of property damage, electric shock, serious injury or death, it is important to read the
precautions below, all labels on the water heater, and the safety messages and instructions throughout this
manual.
Be sure to read and understand the entire Installation and Operation Manual before installing or operating
this water heater, and pay particular attention to the Safety Instructions.
A licensed professional must install the water heater in accordance with the instructions in this manual. The
consumer must read the entire manual to properly operate the water heater. Should you have problems
understanding the instructions in this manual, or have any questions concerning installation or operation of
the water heater, please get help from a qualified service technician, or the local electric utility.
WARNING! Proposition 65 California: This product contains chemicals known to the state of California
to cause cancer, birth defects or other reproductive harm.
SAFETY PRECAUTIONS
It is important to know where the circuit breaker is located. Please ask the installer to show you its location
and how to shut it o if necessary. Turn o the circuit breaker if the water heater has been subjected to
overheating, fire, flood or physical damage.
• Read this manual entirely before installing or operating the water heater.
• Use this appliance only for its intended purpose as described in this Installation and Operation Manual.
 Be sure your appliance is properly installed in accordance with local codes and the provided installation
instructions.
 DO NOT attempt to repair or replace any part of your water heater unless it is specifically recommended in
this manual.
All other servicing should be referred to a qualified technician.

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TRANSPORTATION & STORAGE AT WAREHOUSE
Do not lift or carry using the front bottom part of the water heater. The water heater should be stored in
a dry place, and at a temperature between 32°F and 140°F. In case the water heater is stored without its
packaging, the floor’s slope should be less than 7° to prevent the water heater from falling over.
NOTICE:Long exposure to temperatures above 140°F can cause permanent deformation of the water
heater.
NOTICE:If needed, the water heater can be transported horizontally, however do not lay nor transport the
water heater with the front side facing down (see pictogram on packaging if not removed).
WATER QUALITY
Proper care for your water heater must include evaluation of local water quality conditions. The water
must be potable, free of corrosive chemicals, sand, dirt, and other contaminants. It is up to the installer
to ensure the water fed to the heater does not contain corrosive chemicals or elements that can aect
operation or damage the heat exchanger. Refer to the table below for the maximum allowable limits of
specific parameters according to the EPA in the Code of Federal Regulations. The installer is responsible for
understanding local conditions pertaining to these and other parameters and treating the water as necessary.
Replacement of the heat exchanger and other components due to damage caused by water quality is not
covered by the warranty.
MAXIMUM LEVEL
Total Hardness Up to 200 mg / L
Aluminum * Up to 0.2 mg / L
Chlorides * Up to 250 mg / L
Copper * Up to 1.0 mg / L
Dissolved Carbon Dioxide (CO2) Up to 15.0 mg / L
Iron * Up to 0.3 mg / L
Manganese * Up to 0.05 mg / L
pH * 6.5 to 8.5
TDS (Total Dissolved Solids) * Up to 500 mg / L
Zinc * Up to 5 mg / L
* Source: Part 143 National Secondary Drinking Water Regulations

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INSTALLING THE WATER HEATER
WATER SUPPLY PRESSURE
Minimum Water Pressure: 50 PSI (Recommended
60-80 PSI for maximum performance)
Maximum Water Pressure: 150 PSI
When choosing the location of the water heater,
please take into consideration the following
recommendations.
(Disregarding these recommendations will void the
warranty)
LOCAL INSTALLATION REGULATIONS
This water heater must be installed in accordance with
these instructions, local codes, utility codes, utility
company requirements or, in the absence of local
codes, the latest edition of the National Electrical
Code, which can be found in some local libraries or
can be purchased from the National Fire Protection
Association (website link: https://nfpa.org/).
NOTICE: Please be aware that installation of the
water heater in attics in regions where the outside
air temperature is commonly above 105°F (and
therefore attic temperature can be greater than
140°F) could aect the life of your water heater
electronic controls.
INSTALLATIONS IN CALIFORNIA
For California installation, this water heater must
be braced, anchored, or strapped to avoid falling or
moving during an earthquake.
See following instructions for correct installation
procedures. Detailed instruction may be obtained
from California's Division of the State Architect at
https://dgs.ca.gov/DSA/Contact and from
DSA Headquarters Oce
1102 Q Street, Suite 5100
Sacramento, CA 95811.
4''
17''
1/3 = 20''
2/3 = 41''
45''
4''
1/3 = 20''
6'' min.
(152mm)
6'' min.
(152mm)
2'' min.
(51mm) 2'' min.
(51mm)
Wood ledger 2x4 Gypsum /
fire résistant drywall
Seismic straps
73'' (1844mm)
Control
unit
According to IPC/UPC and California plumbing
code, straps must be installed in hatched areas.
4''
4''
17''
45''
⁄ = 41'' ⁄ = 20''
⁄ = 20''
LOCATION & WATER
HEATER CLEARANCE
Locate the water heater in a clean dry area as near
as practical to the area of greatest heated water
demand. Long uninsulated hot water lines can waste
energy and water.
Place the water heater in such a manner that the
electric junction box, the overflow line cover, the
upper element cover and the lower access panel can
be removed to permit inspection and servicing such
as removal of elements or checking controls.
The water heater and water lines should be protected
from freezing temperatures.
To allow easy access for operation and maintenance,
we recommend leaving the following clearances
around the water heater: At the front and above
the water heater: 25’’. Left and right: 4’’. Back: 2’’
provided that the overflow line can be correctly
installed. In case of any doubt, please check your
local codes.

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To help avoid any potential damage, the water heater
should not be pushed against the back wall.
DO NOT install the water heater OUTDOORS. To
ensure its long life, your water heater MUST be installed
indoors.
Never switch o the water heater. If the water
heater is not going to be used for a period of time
please use the “vacation” temporary function. This
will help to avoid damage caused by freezing.
If the water heater is not going to be used for an
extended period of time, and the electric power
will be shut o, drain your water heater completely
(see page 40).
Make certain the floor underneath the water heater
is strong enough to suciently support the weight of
the water heater once it is filled with water.
CAUTION! Make certain the floor underneath
the water heater is straight and level, and does
not exceed an angle of 1.2°, or ¼ inch per foot.
a < 1.2° (in any directions)
a
Floor
CAUTION! The water heater should not be
located in an area where leakage of the tank
or connections will result in damage to the
area adjacent to it or to lower floors of the
structure. Where such areas cannot be avoided,
it is recommended that a suitable drain pan,
adequately drained, be installed under the water.
DRAIN PAN
1''
min.
A. Width of water heater plus 2” min (22+2”)
B. Depth of water heater plus 2” min (26+2”)
C. Height, maximum 4”
To open drain, line should be at least ⁄” ID and
pitched for proper drainage.
C
B
A
For proper operation of the drain pan, the water heater
must be centered in as far as possible.
NOTICE: Auxiliary drain pan MUST conform to
local codes. Drain Pan Kits are available from the
store where the water heater was purchased, or any
water heater distributor.
Essency manufactures a custom fit drain pan.
NOTICE: We recommend the use of a drain pan,
especially if the water heater is installed in the attic.

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INSULATION BLANKETS
Insulation blankets, available to the general public, for external use on electric water heaters are not
necessary. The purpose of an insulation blanket is to reduce the standby heat loss encountered with storage
tank heaters. This water heater meets or exceeds the National Appliance Energy Conservation Act standards
with respect to insulation and standby loss requirements making an insulation blanket unnecessary.
The manufacturer’s warranty does not cover any damage or defect caused by installation, attachment or use
of any type of energy saving or other unapproved devices (other than those authorized by the manufacturer)
into, onto or in conjunction with the water heater.
The use of unauthorized energy saving devices may shorten the life of the water heater and may endanger
life and property.
The manufacturer disclaims any responsibility for such loss or injury resulting from the use of such
unauthorized devices.
WARNING! If local codes require external application of insulation blanket kits, the manufacturer’s
instructions included with the kit must be carefully followed.
CAUTION! If local codes require the application of an external insulation blanket to this water heater,
pay careful attention to the following so as not to restrict the proper function and operation of the water
heater:
• DO NOT cover the operating or warning labels attached to the water heater or attempt to relocate them
on the exterior of insulation blanket.
 DO NOT apply insulation to the top of the water heater. This could interfere with the safe operation of the
electrical junction box.
 DO NOT cover the access panel(s) to the thermostat(s) and heating element(s).
 DO NOT restrain access to lower cover of the unit. It will result in an overheating of the electronic controls.
• Inspect the insulation blanket frequently.

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1. CONNECTING THE BATTERY
As a back-up in case of power failure, the water heater is equipped with a lithium-ion battery located behind
the lower cover of the unit. To connect this battery, before powering the unit, follow the steps as indicated
on the illustration below:
NOTICE: When reinstalling the cover, do not over-tighten the screws. The applied torque shall not exceed
1.1 lb.ft. After battery connection, the front cover is to be put back on, and left on, for the duration of the
installation.
NOTICE: The battery is intended to be used as an emergency back-up only, in case of power failure, and will
allow you to use the amount of hot water available in your tank at the time of power failure. It will not operate
the water heater heating elements, but only the variable speed pump at a moderate flow rate (corresponding
to a shower flow rate). Neither the touchscreen display nor the WiFi will be operational. It is not meant to be
used continually.
NOTICE: The water heater’s internal drain valve is closed by default from the
factory. Before proceeding with ‘Filling the Water Heater' step (see page 21),
ensure the valve is still closed. In the closed position, the red valve handle
will be facing out. In the open position, the red handle will be facing right.
1) Unscrew the 4 screws
2) Remove the cover
3) Connect the battery
Close
Open
Close
Open

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2. CONNECTING THE WATER SUPPLY
2.1. TYPICAL INSTALLATION
WATER SUPPLY CONNECTIONS
Refer to the illustration above for suggested typical installation. The installation of unions or flexible
connectors is recommended on the hot and cold water connections so that the water heater may be easily
disconnected. To tighten the water connectors, please use a back-up wrench. For ease of maintenance, we
strongly recommend to install service valves in inlet and outlet water circuits (see Flushing the water heater
section page 41). Over-tightening or tightening without a back-up wrench may cause flow sensor damage.
Take special care.
TIP: Water connections are located further to the front of the unit than many other storage water
heaters. Plan accordingly. For example, longer water flexes may be required.
FILTER
Before connecting the cold water supply to the unit, check that the filter is still well installed in the cold inlet
brass fitting. If sediment in the local water supply is an issue, we recommend installing an external Y strainer.
Electrical junction box
(Use only copper conductor) To electric distribution panel
To cold water supply
Shuto valve
Overflow line to suitable open drain
6’’ air gap
Hot water outlet to fixture
Shuto valve
Union
Union
Touchscreen
Upper element access panel
Auxiliary drain pan,
height 4’’ maximum
Drain valve
(Behind the cover)

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OVERFLOW LINE CONNECTION
For ease of installation, the protective cap can be taken o by removing the 2 screws.
We recommend the use of CPVC for the overflow line.
DO NOT over-tighten the connector. The applied torque shall not exceed 2 lb.ft. Make sure the overflow
line opening is at least 6’’ from the ground.
WARNING! In any case, water shall be fully drained to a suitable floor open drain. Respect the correct
slope so that no water can be trapped in the overflow line.
WARNING! Use a ¾’’ MNPT fitting compliant with ASTM D2846 or ASME B16.22 or other standard,
and ensure an inner diameter not less than ⁄’’ (0.625’’).
WARNING! The overflow line piping shall have an inner diameter not less than ¾’’.
WARNING! The protective cap is to be reinstalled after connection of the overflow line.
NOTICE: The overflow line connection is non-pressurized. Using glue for line connection is NOT
recommended as the unit fitting can be damaged in case of future operation on the line.
T/P VALVE
Unlike other tank water heaters, the water in the tank of the Essency EXR is at atmospheric pressure. Per
its construction, UL has evaluated that this water heater does not need a T/P valve. However please refer to
your local codes for specific local requirements.
EXPANSION TANK
This water heater operates at atmospheric pressure. No expansion tank is therefore required. However
please refer to your local codes for specific local requirements.
Electrical junction box
(Use only copper conductor)
Hot water outlet
to fixture
Shuto valve
Union
Union
Touchscreen
Upper element access panel
To electric distribution panel
To cold water supply
Shuto valve
Overflow line to suitable
open drain
Thermal expansion tank
(if required)
TP valve

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HARD WATER INSTALLATION
Based on your water conditions, the heat exchanger may need to be flushed. Contact Essency for more
information. See the Care and Cleaning section on how to proceed (see page 41).
NOTICE: DO NOT apply heat to the hot or cold water connections. If sweat connections are used, sweat
tubing to adapter before fitting adapter to the water connections on the water heater. Any heat applied to
the water supply fittings will permanently damage them or other plastic parts.
NOTICE: Make sure the overflow line is well connected and not obstructed.
NOTICE: DO NOT put any liquid other than water, without any additives, into the tank of the water heater.
2.2. RECIRCULATION
The EXR is recirculation compatible and can be accomplished in one of two ways:
1. With a dedicated return line
2. Without a dedicated return line
In both cases, installers should keep the following in mind when setting up the pump:
• Flow rate delivered by pump should be between 0.3 and 1 GPM. Ideally, the flow rate would be 0.8 GPM.
• Pump should be operating as little as possible and no more than 6 hours per day (for example 3 hours in the
morning, 3 hours in the evening).
For best performance, we recommend limiting each pump ON cycle to less than 2 hours. With built-in
mechanical pin timers, for example, 1:45 ON and :15 OFF is represented by 7 pins up and 1 pin down.
An ON cycle of 2 hours or more may cause a nuisance alarm on the touchscreen related to the leak
detection (see Troubleshooting & Service page 43).
• In any case, it is recommended to limit the velocity in piping < 4 ft/s to avoid any erosion issue.
NOTE: A recirculation system can lead to high heat losses. It is strongly recommended the hot water and
dedicated return lines to be fully insulated.
Following these guidelines will help maintain the full warranty, reduce wear and tear on the entire plumbing
system, save energy, and keep your water heater in optimum operating condition.
If you don’t have another way of confirming flow rate delivered by the recirculation pump, the EXR’s
touchscreen does have the capability of displaying real-time flow rate by following the instructions in the
Useful tips section (see page 37).
Make adjustments to valves, pump speed, etc… until the value on the touchscreen is between 0.3 and 1 GPM
(displayed as 3 - 10).
In addition to the guidelines above, installers must follow all applicable codes and pump manufacturer
instructions.

17
1. With a dedicated return line :
2. Without a dedicated return line :
Cold line
Expansion
tank
Pressure relief
valve
Recirculation
pump
Check
valve
Fixtures
Check
valve
Drain
Cold line
Expansion
tank
Pressure relief
valve
Recirculation
pump
Thermal
bypass valve
Fixtures
Check
valve
Drain

18
3. ELECTRICAL CONNECTION
We require that you contact a plumbing professional for the electrical installation of the water heater. A
separate branch circuit with copper conductors, overcurrent protective device and suitable disconnecting
means must be provided by a qualified electrician. All wiring must conform to local codes or latest edition of
National Electrical Code ANSI/NFPA 70. The water heater is completely wired to the electrical connection
box located at the top of the water heater. An opening for ½” electrical fitting is provided for field wiring
connections. If more than 3 wires need to be connected, for instance for O-Peak installations, the use of a
½” to ¾” adapter is recommended.
The voltage requirements and wattage load for the water heater are specified on the rating plate located at
the top of the water heater.
For ease of installation, it is allowed to temporarily remove the ground plate.
DANGER! Make sure the ground plate is correctly put back in place and the screws are well tightened
(torque 1.5 lb.ft).
The branch circuit wiring should include either:
1. Metallic conduit or metallic sheathed cable approved for use as a grounding conductor and installed with
fittings approved for the purpose.
2. Non-metallic sheathed cable, metallic conduit or metallic sheathed cable not approved for use as a ground
conductor shall include a separate conductor for grounding. It should be attached to the ground terminals
of the water heater and the electrical distribution box.
CAUTION! The presence of water in the piping and water heater does not provide sucient conduction
for a ground. Non-metallic piping, dielectric unions, flexible connectors etc. can cause the water heater
to be electrically isolated.
Junction box cover
Conduit connector
Ground plate
Ground screw
Wire connections

19
SINGLE PHASE WIRING
WARNING: Poor wiring connections, incorrect wire size/type, or wires with too much tension may
result in loss of conductivity or overheating. Take special care that wire jacket is securely connected with
proper means of strain relief before connecting ground and phase wires. Confirm wire connection tabs
are securely closed, tight, and secure before installing junction box cover or turning on power.
WARNING: Be especially careful about the existing wiring on a retrofit. If it is not appropriate for this
application, be sure to upgrade it accordingly. We recommend “SOOW” or “SJOOW” type cords
which are readily available. The key features are stranded wires (which make better contact than solid-
core wires), a voltage rating of 300V or more, and relative flexibility which does not produce any undue
strain on the connectors.
BRANCH CIRCUIT SIZING AND WIRE SIZE GUIDE (use copper conductors only)
Water Heater Wattage Power Supply Voltage Recommended Over
Current Protection*
Copper Wire Size
recommended**
4500 W 240 V 25 A 10 AWG
*Fuse or circuit breaker amperage rating
**Branch circuit sizing and wire size based on National Electric Code (N.E.C. Table 310-16 at 167°F)
ELECTRICAL TERMINAL BOX CONNECTION
WARNING: Your wires need to be stripped of ½”, make sure the wire is
fully inserted into the connector.
To avoid any electrical problem, make sure the position of the shunts corresponds to your connection as
shown below. Please remove the unnecessary shunts from the connection box.
A. Typical connection
Standard 2-phase grounded connection.
Ph 1 - 208VAC/240VAC - 19A.
Phase 1 to both heating elements (T02) and
electronic control (T01).
Ph 2 - 208VAC/240VAC - 19A.
Phase 2 to heating elements (T04 and T05) and
electronic control (T03).
Ground connection (T06 and T07).
½''

20
B. O-Peak
Wire separately the heating elements, in relation with
an O-Peak program.
Ph 1 - 208VAC/240VAC - 19A.
Phase 1 to both heating elements (T02) and
electronic control (T01).
Ph 2 - 208VAC/240VAC - 19A.
Phase 2, Permanent, to upper heating element
(T04) and electronic control (T03).
Ph 2 O Peak - 208VAC/240VAC - 19A.
Phase 2, from the O-Peak meter, to lower heating
element (T05).
Ground connection (T06 and T07).
C. O-Peak - Electronics Separated
Wire separately the elements and electronic control
in case of non permanent power supply to the water
heater and an O-Peak program.
Refer to O-Peak and Electronics Separated
sections.
D. Electronics Separated
Wire separately the elements and electronic control
in case of non permanent power supply to the water
heater.
Ph 1’ - 120VAC/240VAC-50W max.
Phase 1’ to electronic control (T01).
Ph 2’ - 120VAC/240VAC-50W max.
Phase 2’ to electronic control (T03).
Ph 1 - 208VAC/240VAC-19A.
Phase 1 to both heating elements (T02).
Ph 2 - 208VAC/240VAC-19A.
Phase 2 to heating elements (T04 and T05).
Ground connection (T06 and T07).