Bradford White M-2-120R6DS-5500W User manual

238-44422-00K REV 2/11
ELECTRIC WATER HEATER
THE WARRANTY ON THIS WATER HEATER IS IN EFFECT ONLY WHEN
THE WATER HEATER IS INSTALLED AND OPERATED IN
ACCORDANCE WITH LOCAL CODES AND THESE INSTRUCTIONS.
THE MANUFACTURER OF THIS HEATER WILL NOT BE LIABLE FOR
ANY DAMAGE RESULTING FROM FAILURE TO COMPLY WITH THESE
INSTRUCTIONS. READ THESE INSTRUCTIONS THOROUGHLY
BEFORE STARTING.
For your family’s comfort, safety and convenience, it is
recommended this water heater be installed and serviced by a
plumbing professional.
A Spanish language version of these instructions is available by contacting
the manufacturer listed on the rating plate.
La version espanola de estas instruccions se puede obtener al escribirle a la
fábrica cuyo nombre aparece in la placa de especificaciones.
INSTALLATION & OPERATING
INSTRUCTION MANUAL
2
TABLE OF CONTENTS
General Information ........................................................ 3
Installation ....................................................................... 4
Locating The Water Heater......................................... 4
Water Connections...................................................... 6
Electrical Connections................................................13
General Operation...........................................................14
Thermostat Adjustment ..............................................15
Maintenance.....................................................................16
Notes ................................................................................19
CONGRATULATIONS!
You have just purchased one of the finest water heaters on
the market today!
This installation, operation and instruction manual will
explain in detail the installation and maintenance of your
new Electric Water Heater. We strongly recommend that
you contact a plumbing professional for the installation of
this water heater.
We require that you carefully read this manual, as well as
the enclosed warranty, and refer to it when questions arise.
If you have any specific questions concerning your
warranty, please consult the plumbing professional from
whom your water heater was purchased. For your records
we recommend that you write the model, serial number and
installation date of your water heater in the maintenance
section in the back of this manual.
This manual should be kept with the water heater.

3
GENERAL INFORMATION
This electric water heater’s design is certified by Underwriters Laboratories
(UL) and listed in accordance with UL 174. C-UL listed in accordance with
Canadian National Standard C22.2, No. 110-M90.
Water heaters with a capacity of 30 gallons through 80 gallons are evaluated
by UL in accordance with Part 280.707(d) (1) of HUD Mobile Home
Construction and Safety Standards for Energy Efficiency. For mobile home
installations, these water heaters must be installed in accordance with
Section 3280.709 of HUD Mobile Home Construction and Safety Standards
for Installation of Appliances.
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 effect 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.
CAUTION
Incorrect operation of this appliance may create a hazard to life and
property and will nullify the warranty.
DANGER
Do not store or use gasoline or other flammable, combustible, or
corrosive vapors and liquids in the vicinity of this or any other
appliance.
4
General Information continued-
A sacrificial anode is used to extend tank life. Removal of this anode, for any
reason, will nullify the warranty. In areas where water is unusually active, an
odor may occur at the hot water faucet due to a reaction between the
sacrificial anode and impurities in the water. If this should happen, an
alternative anode may be purchased from the supplier that installed this
water heater. This will minimize the odor while protecting the tank.
Additionally, the water heater should be flushed with appropriate dissolvers
to eliminate any bacteria.
INSTALLATION
Locating The Water Heater
This water heater MUST be installed indoors out of the wind and
weather.
This water heater shall NOT be installed in any location where gasoline
or flammable vapors are likely to be present, unless the installation is
such to eliminate the probable ignition of gasoline or flammable
vapors.
The location this water heater is to be installed is of utmost importance.
Before installing this water heater, consult the installation section of these
instructions. After reading these installation and operating instructions,
select a location for the water heater where the floor is level and is easily
accessible to a power supply and water connections. It is recommended
that the water heater be located near the center of greatest hot water usage
to prevent heat loss through the pipes.
IMPORTANT
Before proceeding, please inspect the water heater and it’s 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.
WARNING
Water heaters are heat producing appliances. To avoid damage or injury,
there shall be no materials stored against the water heater and proper care
shall be taken to avoid unnecessary contact (especially by children) with
the water heater. UNDER NO CIRCUMSTANCES SHALL FLAMMABLE
MATERIALS, SUCH AS GASOLINE OR PAINT THINNER BE USED OR
STORED IN THE VICINITY OF THIS WATER HEATER OR ANY
LOCATION FROM WHICH FUMES COULD REACH THE WATER
HEATER.

5
Locating The Water Heater continued-
DO NOT locate the water heater where water lines could be subjected
to freezing temperatures. Locate the water heater so that access
panels and drain valves are accessible. Some models are not equipped
with a drain valve. For those models, install a drain tee in the cold water inlet
as close as practical to the water heater.
Water heater corrosion and component failure can be caused by the heating
and breakdown of airborne chemical vapors. Examples of some typical
compounds that are potentially corrosive are: spray can propellants, cleaning
solvents, refrigerator and air conditioning refrigerants, swimming pool
chemicals, calcium or sodium chloride, waxes and process chemicals.
These materials are corrosive at very low concentration levels with little or no
odor to reveal their presence.
NOTE: DAMAGE TO THE WATER HEATER CAUSED BY EXPOSURE TO
CORROSIVE VAPORS IS NOT COVERED BY THE WARRANTY. DO
NOT OPERATE THE WATER HEATER IF EXPOSURE HAS OR WILL
OCCUR. DO NOT STORE ANY POTENTIALLY CORROSIVE
COMPOUNDS IN THE VICINITY OF THE WATER HEATER.
This water heater must be located in an area where leakage of the tank or
water line connections and the combination temperature and pressure relief
valve will not result in damage to the area adjacent to the water heater or to
lower floors of the structure. When such locations cannot be avoided, a
suitable drain pan must be installed under the water heater. The drain pan
must have a minimum length and width of at least 4 in. (10.2 cm) greater
than the diameter of the water heater. The drain pan, as described above,
can be purchased from your plumbing professional. The drain pan must be
piped to an adequate drain. The piping must be pitched for proper drainage.
To comply with NSF requirements this water heater is to be:
a) Sealed to the floor with sealant, in a smooth and easily cleanable
way, or
b) Installed with an optional leg kit that includes legs and/or extensions
that provide a minimum clearance of 6” beneath the water heater.
Note: For California installation this water heater must be braced,
anchored, or strapped to avoid falling or moving during an earthquake.
See instructions for correct installation procedures. Instructions may
be obtained from DSA Headquarters Office, 1102 Q Street, Suite 5100,
Sacramento, CA 95811.
6
Water Connections
NOTE: BEFORE PROCEEDING WITH THE INSTALLATION, CLOSE THE
MAIN WATER SUPPLY VALVE.
After shutting the main water supply valve, open a faucet to relieve the water
line pressure to prevent any water from leaking out of the pipes while making
the water connections to the water heater. After the pressure has been
relieved, close the faucet. The COLD water inlet and HOT water outlet are
identified on top of the water heater. The fittings at the cold water inlet and
hot water outlet are dielectric waterway fittings with 3/4” NPT tapered male
threads. Make the proper plumbing connections between the water heater
and the plumbing system in the house. Install a shut-off valve in the cold
water supply line.
If this water heater is installed in a closed water supply system, such as the
one having a back-flow preventer in the cold water supply, provisions shall
be made to control thermal expansion. DO NOT operate this water heater in
a closed system without provisions for controlling thermal expansion. Your
water supplier or local plumbing inspector should be contacted on how to
control this situation.
After installation of the water lines, open the main water supply valve and fill
the water heater. While the water heater is filling, open several hot water
faucets to allow air to escape from the water system. When a steady stream
of water flows through the faucets, close them and check all water
connections for possible leaks. NEVER OPERATE THE WATER HEATER
WITHOUT FIRST BEING CERTAIN IT IS FILLED WITH WATER.
CAUTION
If sweat fittings are to be used, DO NOT apply heat to the nipples on top
of the water heater. Sweat the tubing to the adapter before fitting the
adapter to the water connections. It is imperative that heat is not applied
to the nipples containing a plastic liner.
IMPORTANT
FAILURE TO INSTALL AND MAINTAIN A NEW, LISTED 3/4” X 3/4”
TEMPERATURE-PRESSURE RELIEF VALVE WILL RELEASE THE
MANUFACTURER FROM ANY CLAIM WHICH MIGHT RESULT FROM
EXCESSIVE TEMPERATURE AND PRESSURES.

7
Water Connections continued-
WARNING
For protection against excessive temperatures and pressure, install
temperature and pressure protective equipment required by local codes,
but not less than a combination temperature and pressure relief valve
certified by a nationally recognized testing laboratory that maintains
periodic inspection of production of listed equipment or materials, as
meeting the Requirements for Relief Valves and Automatic Gas Shutoff
Devices for Hot Water Supply Systems, ANSI Z21.22, and the Standard
CAN1-4.4 Temperature, Pressure, Temperature and Pressure Relief
Valves and Vacuum Relief Valves. The combination temperature and
pressure relief valve shall be marked with a maximum set pressure, not to
exceed the maximum working pressure of the water heater. The
combination temperature and pressure relief valve shall also have an
hourly rated temperature steam BTU discharge capacity not less than the
hourly input rating of the water heater.
Install the combination temperature and pressure relief valve into the
opening provided and marked for this purpose on the water heater
Note: Some models may already be equipped or supplied with a
combination temperature and pressure relief valve. Verify that the
combination temperature and pressure relief valve complies with local
codes. If the combination temperature and pressure relief valve does not
comply with local codes, replace it with one that does. Follow the
installation instructions above on this page.
Install a discharge line so that water discharged from the combination
temperature and pressure relief valve will exit within six (6) inches (15.3
cm) above, or any distance below the structural floor and cannot contact
any live electrical part. The discharge line is to be installed to allow for
complete drainage of both the temperature and pressure relief valve and
the discharge line. The discharge opening must not be subjected to
blockage or freezing. DO NOT thread, plug or cap the discharge line. It is
recommended that a minimum of four (4) inches (10.2 cm) be provided on
the side of the water heater for servicing and maintenance of the
combination temperature and pressure relief valve.
Do not place a valve between the combination temperature and pressure
relief valve and the tank.
8
Water Connections continued-
WARNING
Hydrogen gas can be produced in a hot water system served by this
water heater that has not been used for a long period of time
(generally two weeks or more). Hydrogen gas is extremely
flammable. 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 flow. There should be no smoking or open
flame near the faucet at the time it is open.
CAUTION
INCREASING THE THERMOSTAT SETTING ABOVE THE PRESET
TEMPERATURE MAY CAUSE SEVERE BURNS AND CONSUME
EXCESSIVE ENERGY. HOTTER WATER INCREASES THE RISK OF
SCALD INJURY.

9
Water Connections continued-
This water heater can deliver scalding temperature water at any faucet in the
system. Be careful whenever using hot water to avoid scalding injury.
Certain appliances, such as dishwashers and automatic clothes washers,
may require increased temperature water. By setting the thermostat on this
water heater to obtain increased temperature water required by these
appliances, you may create the potential for scald injury. To protect against
injury, you should install an ASSE approved mixing valve in the water
system. This valve will reduce point of discharge temperature by mixing cold
and hot water in branch supply lines. Such valves are available from the
manufacturer of this water heater or a local plumbing supplier. Please
consult with a plumbing professional.
APPROXIMATE TIME/TEMPERATURE RELATIONSHIPS IN SCALDS
120°F (49°C) More than 5 minutes
125°F (52°C) 1½ to 2 minutes
130°F (54°C) About 30 seconds
135°F (57°C) About 10 seconds
140°F (60°C) Less than 5 seconds
145°F (63°C) Less than 3 seconds
150°F (66°C) About 1½ seconds
155°F (68°C) About 1 second
(52°C) can cause severe burns
are at highest risk of being
Children, disabled and elderly
instantly or death from scalds.
Water temperature over 125°F
Feel water before bathing or
before setting temperature
available.
showering.
Temperature limiting valves are
Review this instruction manual
at water heater.
scalded.
10
Water Connections continued-
Upright Models (See Figures 1A & 1B)
The hot and cold water connections are identified on the top of the water
heater (See figure 1A). For bottom inlet models (-503 models), the cold
water inlet is located on the side of the drain valve (see figure 1B). Connect
the hot and cold water lines to the installed nipples using unions. Install a
listed temperature-pressure relief valve in the opening on the side of the
water heater.
Figure 1A (Top Inlet Models)
Figure 1B (Bottom Inlet Models)

11
Water Connections continued-
Utility Models (See Figure 2)
All utility models are supplied with inlet and outlet nipples located in a plastic bag
attached to the water heater. The hot and cold water locations are identified on
the side of the water heater. Apply appropriate amount of thread sealant to the
provided nipples and install nipples into the side of the tank. For 20 gallon utility
models, install the supplied anode/nipple combination at the HOT outlet location.
Connect the hot and cold water lines to the nipples using unions. Install a listed
temperature-pressure relief valve in the opening on the side of the water heater.
Install a vacuum relief anti-siphon device in the cold water inlet line when using
side cold water connection.
The 6 and 12 gallon models are equipped for installation with either side or top
water connections. They are shipped from the factory with the alternate top
connections plugged. The alternate top inlet is supplied with a dip tube. If the top
water connections are needed, remove pipe plugs from the alternate top
connections, apply appropriate amount of thread sealant to the provided nipples
and install nipples in desired top location. Apply appropriate amount of thread
sealant to the pipe plugs and install pipe plugs in the side locations. Install a
vacuum relief anti-siphon device in the cold water inlet line when using side cold
water connection.
Figure 2
12
Water Connections continued-
Table Top Models (See Figure 3) The hot water outlet and cold water
inlet are identified on the back panel of the water heater. Referring to figure
3, remove the two screws that are holding the service access panel in place.
Remove front panel for access. Wedge a flat bladed screwdriver into the
front joint between the top and side panels and force the top panel upward.
This will separate the top panel from the water heater and allow further
access to the water heater.
Check drain valve to make sure that it is closed. Part the top fiberglass
insulation to allow access to the plumbing and electrical connections.
Connect the cold water supply line and hot water outlet lines using elbows,
nipples and unions as shown in the diagrams. Install a shutoff valve in the
cold water inlet. A listed temperature-pressure relief valve has been factory
installed. Plumb the discharge as shown.
Figure 3

13
Electrical Connections
Before any electrical connections are made, be sure that the water heater is
full of water and that the manual shut-off valve in the cold water supply line is
open. Check the rating plate and wiring diagram before proceeding. This
electric water heater was built and wired in accordance with the Underwriters
Laboratories testing approvals requirements. The temperature limiting
device is of the manual reset, trip-free type and has been factory installed to
interrupt all ungrounded power supply conductors in the event of thermostat
failure. Thermostats are factory set and wired in accordance with the wiring
diagram fastened to the inside of the top access panel. The plumbing
supplier in your area ordered this heater wired at the factory to comply with
existing area codes, but local utility codes may require or allow other
circuitry. Consult your local power company to determine the correct
electrical hook-up in order to meet local utility and building codes and in
order to obtain the most economical rates. Also check to find out if you are
required to obtain a permit before starting the installation. The following
chart shows the recommended fuse size for the maximum water heater
wattage. The maximum wattage and rated voltage are shown on the water
heater data plate. The water heater must be well grounded. A green ground
screw is provided at the electrical connection point for connecting a ground
wire. Ground screw on 10 & 15-gallon models is located under the
removable element cover.
Recommended Fuse size
Voltage
Max. Watts 120v 208v 240v 277v 480v
1000 15A 10A 10A 10A 10A
1250 15A 10A 10A 10A 10A
1500 20A 10A 10A 10A 10A
2000 25A 15A 15A 10A 10A
2500 30A 15A 15A 15A 10A
3000 35A 20A 20A 15A 10A
3500 --- 25A 20A 20A 10A
4000 --- 25A 25A 20A 15A
4500 --- 30A 25A 25A 15A
5000 --- 30A 30A 25A 15A
5500 --- 35A 35A 25A 15A
6000 --- 40A 35A 30A 20A
14
GENERAL OPERATION
When the switch is closed, the operation of this electric water heater is
automatic. The thermostats are preset to the “HOT” setting to provide a
water temperature of approximately 120°F (49°C) to reduce the risk of scald
injury.
Care must be taken whenever using hot water to avoid scalding injury.
Certain appliances require high temperature hot water (such as dishwashers
and automatic clothes washers).
TO FILL THE WATER HEATER
1. Close the water heater drain valve (if provided) by inserting a standard
flat head screwdriver into the slot and turning clockwise.
2. Open the cold water supply shut-off valve.
3. Open several hot water faucets to allow air to escape from the system.
4. When a steady stream of water flows from the faucets, the water heater
is filled. Close the faucets and check for water leaks at the water heater
drain valve, combination temperature and pressure relief valve and the
hot and cold water connections.
TO DRAIN THE WATER HEATER
Should it become necessary to completely drain the water heater, make sure
you follow the steps below:
1. Disconnect the power supply to the water heater. Consult the plumbing
professional or electric company in your area for service.
2. Close the cold water supply shut-off valve.
3. Open the drain valve (if provided) on the water heater by inserting a
standard flat head screwdriver into the slot and turning counter-
clockwise. The drain valve has threads on the end that will allow
connection of a standard hose coupling. For those models not equipped
with a drain valve, disconnect cold water inlet piping at a convenient
connection location as close to an adequate drain as possible.
CAUTION! THIS WATER MAY BE HOT.
4. Open a hot water faucet to allow air to enter the system.
To refill the water heater, refer to “TO FILL THE WATER HEATER.”
Before closing the switch to allow electric current to flow to the
water heater, make certain that the water heater is full of water and
that the cold water inlet valve is open. Complete failure of the
heating element(s) will result if they are not totally immersed in
water at all times. Failure of the element(s) due to dry-firing is not
covered by warranty.
CAUTION
Scalding may occur within five (5) seconds at a temperature setting of
140°F (60°C).

15
Thermostat Adjustment
The temperature of the water can be changed by adjusting the thermostat(s).
Before any work is done on the water heater, disconnect all power to the
water heater by opening the switch at the main electrical circuit breaker or
fuse box. Remove the access panels or front panel on table tops, fold the
insulation outward away from the controls. Set the thermostat(s) to the
desired water temperature using a screwdriver to move the thermostat dial.
The thermostat has been factory preset to approximately 120°F (49°C).
Rotate the temperature dial clockwise to increase water temperature.
Replace the insulation making sure that the controls are well covered and
that the plastic terminal shield has not been displaced; replace the access
panel. The water heater is now ready for operation and the main switch can
be closed.
Figure 4
CAUTION
Before adjusting thermostat(s), turn off power supply to the water heater.
Hotter water increases the risk of scald injury. Scalding may occur within
five (5) seconds at a temperature setting of 140°F (60°C). To protect
against hot water injury, install an ASSE approved mixing valve in the water
system. This valve will reduce point of discharge water temperatures by
mixing cold and hot water in branch water lines. A licensed plumbing
professional or local plumbing authority should be consulted.
Note: This water heater is equipped with an energy cut out device to
prevent overheating. Should overheating occur, turn off the electrical supply
to the water heater and contact a qualified service technician.
DANGER
16
MAINTENANCE
Shut off the electric power whenever the water supply to the water heater is
off. Shut off the electric power and water supply, drain the water heater
completely to prevent freezing whenever the building is left unoccupied
during the cold weather months. In order to insure efficient operation and
long tank life, drain the water heater at least once a month through the drain
valve until the water runs clear. Failure to do this may result in noisy
operation and lime and sediment buildup in the bottom of the tank. Check
the temperature-pressure relief valve to insure that the valve has not
become encrusted with lime. Lift the lever at the top of the valve several
times until the valve seats properly without leaking and operates freely.
The following maintenance should be performed by a qualified service
technician at the minimum periodic intervals suggested below. In some
installations, the maintenance interval may be more frequent depending on
the amount of use and the operating conditions of the water heater. Regular
inspection and maintenance of the water heater will help to insure safe and
reliable operation.
1. Annually, check the operation of the thermostat(s).
2. Bi-annually, check the seal around the heating elements for leaks. If there
is any sign of leaking, disconnect the power supply to the water heater
and contact the plumbing professional that installed this water heater or a
qualified service technician.
IMPORTANT
The water heater should be inspected at a minimum of annually by a
qualified service technician for damaged components. DO NOT operate
this water heater if any part is found damaged.
WARNING
When lifting lever of temperature-pressure relief valve, hot water will be
released under pressure. Be certain that any released water does not
result in bodily injury or property damage. The magnesium anode rod
should be inspected periodically and replaced when necessary to prolong
tank life.

17
Maintenance continued-
3. At least once a year, check the combination temperature and pressure
relief valve to insure that the valve has not become encrusted with lime.
Lift the lever at the top of the temperature-pressure relief valve several
times until the valve seats properly without leaking and operates freely.
4. If the combination temperature and pressure relief valve on the appliance
discharges periodically, this may be due to thermal expansion in a closed
water supply system. Contact the water supplier or local plumbing
inspector on how to correct this situation. Do not plug the combination
temperature and pressure relief valve outlet for any reason.
5. Monthly, drain off a gallon of water from the water heater to remove silt
and sediment.
6. A combination sacrificial anode rod/hot water outlet nipple has been
installed to extend tank life. The anode rod should be inspected
periodically (every 2 years) and replaced when necessary to prolong tank
life. Water conditions in your area will influence the time interval for
inspection and replacement of the anode rod. Contact the plumbing
professional who installed the water heater or the manufacturer listed on
the rating plate for anode replacement information. The use of a water
softener may increase the speed of anode consumption. More frequent
inspection of the anode is needed when using softened (or phosphate
treated) water.
WARNING
When lifting lever of temperature-pressure relief valve, hot water will be
released under pressure. Be certain that any released water does not
result in bodily injury or property damage.
WARNING! THIS WATER MAY BE HOT.
CAUTION
FOR YOUR SAFETY, DO NOT ATTEMPT TO REPAIR THERMOSTAT(S),
HEATING ELEMENTS, OR ELECTRICAL WIRING. REFER SUCH
REPAIRS TO A QUALIFIED SERVICE TECHNICIAN.
18
Maintenance continued-
Contact your local plumbing supplier or plumbing professional for
replacement parts or contact the company at the address displayed on the
rating plate of the water heater.
For faster and better service, please provide the part name, model, and
serial number(s) of the water heater(s) when ordering parts.
READ THE WARRANTY FOR A FULL EXPLANATION OF THE LENGTH
OF TIME THAT PARTS AND THE WATER HEATER ARE WARRANTED.
Complete the following information and retain for future reference:
Model
No:________________________________________________________
Serial No:___________________________________________________
Service Phone
Days: ______________________Nights:___________________________
Address:_____________________________________________________
Supplier:_____________________________________________________
Supplier Phone
No:_________________________________________________________
Manufactured under one or more of the following U.S. Patents: RE.34,534;
B1 5,341,770; 4,416,222; 4,628,184; 4,669,448; 4,672,919; 4,808,356; 4,829,983;
4,861,968; 4,904,428; 5,000,893; 5,023,031; 5,052,346; 5,081,696; 5,092,519;
5,115,767; 5,199,385; 5,277,171; 5,372,185; 5,485,879; 5,574,822; 5,596,952;
5,660,165; 5,682,666; 5,761,379; 5,943,984; 5,954,492; 5,988,117; 6,142,216;
6,395,280; 6,684,821; 7,007,748; 7,063,132;
Other U.S. and Foreign patent applications pending. Current Canadian Patents:
1,272,914; 1,280,043; 1,289,832; 2,045,862; 2,092,105; 2,107,012; 2,108,186;
2,112,515

19
NOTES
20
NOTES