Bradford White SW-2-40R-L User manual

238-43480-00L REV 8/20
INDIRECT-FIRED
WATER HEATER
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 MANUAL
WITH PARTS LISTING AND TROUBLESHOOTING GUIDE
For your family’s comfort, safety, and convenience, we
recommend this water heater be installed and serviced by a
plumbing professional.
WARNING
To avoid damage or injury, there
must be no materials stored
against the indirect water heater
and proper care shall be taken
to avoid unnecessary contact
(especially by children) with the
indirect water heater.
•DO NOT store or use
gasoline or other flammable
liquids in the vicinity of this
water heater or any other
appliance.

2
TABLE OF CONTENTS
I-
IMPORTANT INFORMATION…………….…..
3
II-
SPECIFICATIONS……………………………….
7
III-
GENERAL INFORMATION…………………….
10
IV-
PRE-INSTALLATION……………………………
12
V-
WATER CONNECTIONS………………………..
17
VI-
ELECTRICAL CONNECTIONS………………..
22
VII-
OPERATING INSTRUCTIONS…………………
23
VIII-
MAINTENANCE………………………………….
26
IX-
TROUBLESHOOTING GUIDE…………………
29
X-
PARTS LIST……………………………………….
31
NOTES……………………………………………..
32
CONGRATULATIONS!
You have 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
indirect 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 if 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 back of this manual.
This manual should be kept with the water heater.
We’re committed to providing you with the finest water heater
made.

3
SECTION I
IMPORTANT INFORMATION
-READ CAREFULLY-
The equipment must be installed in accordance with those installation
regulations required in the area where the installation is to be made.
These regulations must be carefully followed in all cases. Authorities
having jurisdiction shall be consulted before installations are made.
All wiring on water heaters installed in the USA must be in accordance
with the National Electrical Code and/or local regulations; or in Canada,
installed in accordance with the Canadian Electrical Code and/or local
regulations.
The following terms are used throughout this manual to bring attention to the
presence of hazards of various risk levels, or to important information
concerning product life.
CAUTION
The maximum boiler water supply temperature to the indirect heat
exchanger must NOT exceed 240°F (115°C).
NOTICE
Insulation blankets are not required for this water heater. This
water heater meets or exceeds the ASHRAE/IES 90.1b standards
with respect to insulation and standby loss requirements.
DANGER
Indicates an imminently
hazardous situation, which,
if not avoided, will result in
death, serious injury, or
substantial property
damage.
CAUTION
Indicates a potentially
hazardous situation, which,
if not avoided, may result in
moderate, or minor injury or
property damage.
WARNING
Indicates a potentially
hazardous situation, which,
if not avoided, could result
in death, serious injury, or
substantial property
damage.
NOTICE
Indicates special
instructions on installation,
operation or maintenance,
which are important but not
related to personal injury
hazards.

4
Important Information continued-
DANGER
DO NOT store or use gasoline or other flammable, combustible, or
corrosive vapors and/or liquids in the vicinity of this or any other
appliance.
IF YOU SMELL GAS:
•DO NOT try to light any appliance.
•DO NOT touch any electric switch; DO NOT use any telephone in
your building.
•Immediately call your gas supplier from a telephone in another
building. Follow the gas supplier’s instructions.
•If you cannot reach your gas supplier, call the fire department
DO NOT OPERATE THE APPLIANCE UNTIL THE LEAKAGE IS
CORRECTED!
Liquefied petroleum gas/propane gas is heavier than air and will
remain at floor level if there is a leak. Basements, crawl spaces,
closets, and areas below ground level will serve as pockets for
accumulation of leaking gas.
This water heater is supplied with an adjustable thermostat to control
water temperature. Hot water temperatures required for automatic
dishwasher and laundry use can cause scald burns resulting in
serious personal injury and/or death. The temperature at which injury
occurs varies with the person’s age and the time of exposure. The
slower response time of disabled persons increases the hazards to
them. NEVER allow small children to use a hot water tap or to draw
their own bath water. NEVER leave a child or disabled person
unattended in a bathtub or shower.

5
Important Information continued-
WARNING
Installation is not complete unless a pressure and temperature
relief valve is installed into the side of the water heater. See the
Water Connections section of this manual for details.
This water heater contains very hot water under high pressure. Do
NOT unscrew any pipe fittings or attempt to disconnect any
components of this water heater without positively assuring the
water is cool and has no pressure. Always wear protective clothing
and equipment when installing, starting up, or servicing this water
heater to prevent scald injuries. Do NOT rely on the pressure and
temperature gauges to determine the temperature and pressure of
the water heater. This water heater contains components that
become very hot. Do NOT touch any components unless they are
cool.
Improper installation, adjustments, alteration, service or
maintenance can cause property damage, personal injury or loss of
life. Failure to follow all instructions in the proper order can cause
personal injury or death. Read and understand all instructions,
including all those contained in component manufacturer’s
manuals, which are provided with the appliance before installing,
starting-up, operating, maintaining, or servicing this appliance.
Keep this manual and literature in legible condition and posted
near the appliance for reference by owner and service technician.
This water heater requires regular maintenance and service to
operate safely. Follow the instructions contained in this manual.
Installation, maintenance, and service must be performed only by
an experienced, skilled, and knowledgeable installer or service
agency.
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.

6
Important Information continued-
WARNING
It is the responsibility of the installing contractor to see that all
controls are correctly installed and are operating properly when the
installation is complete.
DO NOT operate the water heater with jumpered or absent controls
or safety devices.
DO NOT tamper with or alter the water heater and/or controls.
DO NOT operate the water heater if any external part has been
under water. Immediately call a qualified service technician to
inspect the appliance and to replace any part of the control system
that was under water.
This water heater is suitable for installation on combustible
flooring. DO NOT install this water heater on carpeting.
DO NOT operate this water heater without first being certain it is
filled with water.
Flammable items, pressurized containers, or any other potential
fire hazardous articles must never be placed on or adjacent to the
heater. Containers of flammable gases should not be stored or
used in the same room with this water heater.
Hydrogen gas can be produced in an operating water heater that
has not had water drawn from the tank 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 that the water faucet be opened for
several minutes at the kitchen sink before you use any electrical
appliance that is connected to the hot water system. If hydrogen is
present, there will be unusual sounds such as air escaping through
the pipes as hot water begins to flow. Do NOT smoke or have open
flame near the faucet at the time it is open.

7
SECTION II
SPECIFICATIONS
Figure 1 –Tank Layout
Table 1: Water Heater Dimension (Inches)
Model
A
B
C
D
E
F
30-Gal. / Res.
22
33-5/8
28-1/4
34-3/8
5-3/8
27-1/2
40-Gal. “R” / Res.
22
41-1/8
34-3/8
41-7/8
5-3/8
27-1/2
50-Gal. “R” / Res.
22
46-1/4
40-1/8
47
5-3/8
27-1/2
65-Gal. / Res.
22
59-1/4
53-1/8
60
5-3/8
27-1/2
65-Gal. / Com.
22
59-1/4
53-1/8
60
5-3/8
47-3/4
80-Gal. / Res.
24
59
52-7/8
59-3/4
5-3/8
27-1/2
80-Gal. / Com.
24
59
52-7/8
59-3/4
5-3/8
47-3/4
120-Gal. / Res.
28-1/4
62-1/2
55-3/4
63-1/4
6-3/8
28-1/2
120-Gal. / Com.
28-1/4
62-1/2
55-3/4
63-1/4
6-3/8
48-3/4

8
Specifications continued-
Table 2: Water Heater Capacities
Model
Tank
Capacity
(Gal)
Coil Volume
(Gal)
Dry Weight
(Lbs)
Wet Weight
(Lbs)
30-Gal. / Res.
29
2.7
140
404
40-Gal. “R”/ Res.
37
2.7
172
486
50-Gal. “R” / Res.
43
2.7
180
576
65-Gal. / Res.
57
2.7
196
704
65-Gal. / Com.
54
5.0
265
768
80-Gal. / Res.
71
2.7
224
861
80-Gal. / Com.
67
5.0
293
920
120-Gal. / Res.
110
2.7
355
1324
120-Gal. / Com.
107
5.0
415
1370
Table 3: AHRI Certified Water Heater Ratings
Model
First Hour
Rating
(Gal/Hr)
Continuous
Draw
Rating
(Gal/Hr)
Standby
Heat Loss
Rating
(°F/Hr)
Minimum
Heat Output
Rate of the
Heat Source
(BTU/Hr)
Minimum
Heat
Source
Flow Rate
(Gal/Min)
30-Gal. /
Res.
197
180
1.2
120,000
13.7
40-Gal.
“R” / Res.
205
180
1.1
120,000
13.7
50-Gal.
“R” / Res.
210
180
0.9
120,000
13.7
65-Gal. /
Res.
215
175
0.8
115,000
13.7
65-Gal. /
Com.
370
335
0.8
225,000
14.0
80-Gal. /
Res.
235
175
0.6
115,000
13.7
80-Gal. /
Com.
380
335
0.6
225,000
14.0
120-Gal. /
Res.
265
175
0.4
115,000
13.7
120-Gal. /
Com.
400
325
0.4
220,000
14.0
NOTES: These ratings were obtained with a heat source output rate
and flow rate as specified in Table 3 and a 180°F boiler water supply
temperature. Other results will be obtained under different conditions.

9
Specifications continued-
Table 4: Water Heater Performance
Model
Maximum First
Hour Rating
(Gal/Hr) @
140°F 115°F
Continuous
Draw Rating
(Gal/Min) @
140°F 115°F
Approximate
Boiler Output
Needed For
Ratings (BTU/hr)
30-Gal. / Res.
226
342
3.3
5.2
180,000
40-Gal. “R” / Res.
235
351
3.3
5.2
180,000
50-Gal. “R” / Res.
244
360
3.3
5.2
180,000
65-Gal. / Res.
258
374
3.3
5.2
180,000
65-Gal. / Com.
396
582
5.7
8.8
300,000
80-Gal. / Res.
272
388
3.3
5.2
180,000
80-Gal. / Com.
408
594
5.7
8.8
300,000
120-Gal. / Res.
309
425
3.3
5.2
180,000
120-Gal. / Com.
445
631
5.7
8.8
300,000
NOTES: Based on 200°F boiler water temperature and 50°F potable
water inlet temperature.
Table 5: Water Heater Performance
MODEL
Hot Water
Availability
(Minutes)
Coil Heat
Transfer Area
(Sq Ft)
Pressure Drop at
Rated Heat Source
Flow Rate
(Feet of Head)
30-Gal. / Res.
5.5
14.2
1.5
40-Gal. “R” / Res.
7.5
14.2
1.5
50-Gal. “R” / Res.
9.0
14.2
1.5
65-Gal. / Res.
11.0
14.2
1.5
65-Gal. / Com.
10.5
27.2
5.0
80-Gal. / Res.
13.5
14.2
1.5
80-Gal. / Com.
13.2
27.2
5.0
120-Gal. / Res.
20.8
14.2
1.5
120-Gal. / Com.
20.6
27.2
5.0

10
Specifications continued-
NOTICE
If the boiler takes longer to heat up from a cold start than the water
availability as noted above, hot water shortage may occur.
Hot water availability is based off drawing 80% of the heated tank
volume at 4 gallons per minute flow rate.
The maximum heat transfer through the coil (heat input) of the
water heater at 240°F boiler water supply temperature and 210°F
potable water temperature is 94,100 Btu/hr for residential models
and 180,300 Btu/hr for commercial models. Potable water
temperature is limited to below 210°F and nominal water-containing
capacity is below 120 gallons for all indirect-fired models.
Accordingly, per Part HLW-101.2, Section IV of the ASME Boiler
and Pressure Vessel Code, all indirect-fired products listed are
exempted from compliance with the code.
SECTION III
GENERAL INFORMATION
FEATURES
This water heater contains the following features:
HEAT EXCHANGER –The heat exchanger (coil) has 1” NPT female
fittings.
These water heaters with single-wall heat exchangers meets the
Uniform Plumbing Code for installation in all potable water systems
provided that:
•The boiler water (including additives) is practically non-toxic,
having toxicity rating of class of 1 as listed in Clinical Toxicology
of Commercial Products.
•The boiler water pressure is limited to maximum 30 psig by
approved relief valve.
•The heat transfer medium is potable water or contains only
substances that are recognized as safe by the U.S. Food and Drug
Administration (FDA).
•The pressure of the heat transfer medium is maintained less than
the normal minimum operating pressure of the potable water
system.
•The equipment is permanently labeled to indicate that only
additives recognized as safe by the FDA shall be used in the heat
transfer medium.

11
ADJUSTABLE AQUASTAT –The thermostat can read from 40°F to
180°F. The temperature may be adjusted from 80°F to 160°F with installed
factory stops. The aquastat (thermostat) was adjusted to 120°F before the
heater was shipped from the factory. It is recommended that lower
temperatures be used to avoid the risk of scalding. Refer to the “Warnings”
and the section on SCALDING in “Section VII – Operating Instructions.” It is
further recommended, in all cases, that the water temperature be set for the
lowest temperature that satisfies your hot water needs. This will also provide
the most energy efficient operation of the water heater and minimizes scale
formation.
Setting the water heater temperature at 120°F will reduce the risk of scalds.
Some states require settings to specific lower temperatures.
TEMPERATURE AND PRESSURE RELIEF VALVE
WARNING
Keep clear of the combination temperature and pressure relief valve
discharge line outlet. The discharge may be hot enough to cause scald
injury. The water is under pressure and may splash. 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 of the Standard 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 must 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 must also have an
hourly rated temperature steam BTU discharge capacity not less than the
hourly rating of the water heater. The supplied combination temperature
and pressure relief valve, when properly installed and unrestricted, will
discharge the maximum input produced by a 240°F (115°C) boiler supply
temperature. A lower boiler supply temperature will reduce the input
required to be discharged in the event of excessive potable water
temperatures.
Install the combination temperature and pressure relief valve into the
opening provided and marked for this purpose on the water heater.
Some models may already be equipped or supplied with a temperature
and pressure relief valve. Verify that the combination temperature and
pressure relief valve complies with local codes. If the temperature and
pressure relief valve does not comply with local codes, replace it with one
that does.

12
General Information continued-
WARNING
Install a discharge line so that water discharged from the temperature
and pressure relief valve will exit within six (6) inches 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 clearance of four (4) inches 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!
SACRIFICIAL ANODES –Three sacrificial anode rods have been
installed in the tank head to extend tank life. The removal of any anodes,
except for inspection and/or replacement, will nullify the warranty. The
anode rods should be inspected annually to determine the amount of
sacrificial decay 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. 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. Contact the
plumbing professional who installed the water heater or the manufacturer,
listed on the rating plate, for anode replacement information.
SECTION IV
PRE-INSTALLATION
UNPACKING
INSPECT SHIPMENT carefully for any signs of damage. If damage
is noted, do not install the product. Contact the shipper or
manufacturer. All equipment is carefully manufactured, inspected,
and packed. Our responsibility ceases upon delivery of the packaged
heater to the carrier in good condition.
NOTE: Any claims for damage or shortage in shipment must be filed
immediately against the carrier by the consignee.

13
Pre-installation continued-
IMPORTANT DECISIONS REQUIRED BEFORE
INSTALLATION
SIZING
1. Boiler DOE Heating Capacity –The indirect-fired water heater
will provide the rated performance only if used in conjunction with
a heat source with a DOE heating capacity (Boiler Output) at least
as much as the minimum noted in Table 3. If the heat source has
less capacity, the output of the tank will be reduced. To determine
the approximate reduction in output from the tank use the
following formula:
New Rating = (maximum continuous draw rating) x
Actual Boiler Output Capacity
Minimum Boiler Output Capacity
For example, what would the continuous draw rating be if a 50-gallon
indirect-fired heater were installed with a heat source having a DOE
heating capacity of 110,000 BTU/h?
Answer:
New Rating
= 180 gal/hr x (110,000 BTU/h)/(120,000 BTU/h)
= 180 gal/hr x 0.917 = 165 gal/hr
NOTICE
Increasing the boiler DOE heating capacity above the values
listed in Table 3 will not increase the rating of the water heater.
2. Circulator Sizing –Refer to Table 5 for the corresponding
pressure drop through the coil for the given model. Calculate the
pressure drop of all straight pipe and fittings on the supply and
return of the water heater at the selected flow rate. Add the
piping/fitting pressure drop to the pressure drop through the water
heater coil.
Select a circulator that will provide an appropriate flow rate at the
combined pressure drop.

14
Pre-installation continued-
SYSTEM ZONE CONTROL
The indirect-fired water heater must be installed as a zone separate
from the space heating system. The domestic hot water zone’s
piping and circulator must be sized for a minimum flow rate with all
zones in use and a maximum flow rate with only the water heater in
use. For this reason, the preferred method of zone control is with
circulators.
1. Circulators –With space heating zones using circulators, the
indirect-fired heater should be added as an additional zone with a
circulator.
2. Zone Valves –Select a valve with a low-pressure drop to assure
adequate flow through the water heater.
3. Hybrid –The space heating zone can be zoned using zone
valves and the indirect-fired heater zoned with a circulator.
DOMESTIC HOT WATER PRIORITY
Two options are available, Priority and Non-Priority.
1. Priority –Demand for space heating is interrupted or postponed
until the domestic hot water demand is satisfied. This option
provides maximum delivery of domestic hot water. Priority is
recommended when:
a) Boiler net output is 100,000 Btu per hour or less, or
b) When boiler output required to satisfy domestic hot water
demand is at least 50% of the boiler output required to satisfy
space heating demand, or
c) When an interruption in space heating can be tolerated during
a long domestic hot water draw.
2. Non-Priority –Boiler output is divided between space heating
and domestic hot water heating. Delivery of domestic hot water
can be reduced during simultaneous space and domestic hot
water heating operations, depending on such factors as boiler
output, boiler over-sizing, number of space heating zones calling
for heat, and the ratio of domestic hot water load to space
heating load.

15
Pre-installation continued-
COMPONENT LOCATION
CAUTION
This water heater must be located in an area where leakage of
the tank, water line connections, or the 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 depth must be
suitable for draining and collecting water and have a minimum
length and width of at least four (4) inches measured from the
jacket 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 at least
¾ inch in diameter and pitched for proper drainage.
Clearance from Combustible Materials
Top
Sides
Front
Rear
0”
0”
0”
0”
Table 6: Combustible Material Clearances
Recommended Service Clearances
Non-Piping
Side
Front
(Aquastat)
Rear
T & P Relief
Valve Side
4”
16”
0”
4”
Table 7: Service Clearances
CAUTION
DO NOT drop water heater. DO NOT bump water heater jacket
against floor.

16
Pre-installation continued-
APPLIANCE LOCATION
1. Boiler Location –Locate the indirect-fired water heater as close
to the boiler as practical.
2. Fixture Locations –For fastest delivery of hot water, place the
indirect-fired water heater close to points of use.
ADDITIONAL RECOMMENDED COMPONENTS
1. Shut-off Valves –Allows isolation of water heater from
domestic water system and/or boiler system during service.
2. Unions –Allows water heater movement during service if
adequate clearance cannot be provided.
3. Thermal Expansion Tank –If the water heater is installed in a
closed water supply system, such as one having a back-flow
preventer in the cold water line, provide thermal expansion
control. Contact the water supplier or local plumbing inspector
for additional information.
WARNING
DO NOT plug the inlet and outlet tappings of tankless heater left
installed in the boiler.
MOVE THE WATER HEATER TO A PERMANENT
POSITION BY SLIDING OR WALKING.
NOTICE
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, California 95811.

17
SECTION V
WATER CONNECTIONS
WARNING
FAILURE TO INSTALL AND MAINTAIN A NEW, LISTED
TEMPERATURE AND PRESSURE RELIEF VALVE WILL
RELEASE THE MANUFACTURER FROM ANY CLAIM WHICH
MIGHT RESULT FROM EXCESSIVE TEMPERATURE AND
PRESSURES.
Hydrogen gas can be produced in an operating water heater that
has not had water drawn from the tank for a long period of time.
HYDROGEN GAS IS EXTREMELY FLAMMABLE. To prevent the
possibility of injury under these conditions, we recommend the hot
water faucet be opened for several minutes at the kitchen sink
before you use any electrical appliance that is connected to the hot
water system. If hydrogen is present, there will be an unusual sound
such as air escaping through the pipes as hot water begins to flow.
DO NOT smoke or have open flame near the faucet at the time it is
open.
Keep clear of the temperature and pressure relief valve discharge
line outlet. The discharge may be hot enough to cause scald injury.
The water is under pressure and may splash.
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.
INSTALL TEMPERATURE AND PRESSURE RELIEF VALVE
(if not factory installed)
WARNING
Temperature and pressure relief valve discharge piping must be
piped near the floor to eliminate potential of severe burns. DO NOT
pipe in any area where freezing could occur. DO NOT install any
shut-off valves, plugs or caps to the temperature and pressure relief
valve or piping.

18
Water Connections continued-
INSTRUCTIONS FOR POTABLE CONNECTIONS
1. BEFORE PROCEEDING WITH THE INSTALLATION, CLOSE
THE MAIN WATER SUPPLY VALVE. After shutting off the main
water supply, 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 the top of the water heater. Make
the proper plumbing connections between the water heater and
the plumbing system to the house. Install a shut-off valve in the
cold water supply line.
2. If this water heater is installed in a closed water supply system,
such as one having a back-flow preventer in the cold water
supply, provisions must be made to control thermal expansion.
DO NOT operate this water heater in a closed system without
provisions for controlling thermal expansion. Warranties do not
cover damages from thermal expansions such as pressure
bulges and/or deformities. A properly sized expansion tank will
alleviate most problems. Your water supplier or local plumbing
inspector should be contacted on how to control this situation.
3. 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 steady streams of water flow through the
faucets, close them and check all water connections for
possible leaks.
4. NEVER OPERATE THE WATER HEATER WITHOUT FIRST
BEING CERTAIN THAT IT IS FILLED WITH WATER.
INSTRUCTIONS FOR BOILER CONNECTIONS
The indirect-fired heater connection labeled “To Boiler Return” should
be piped to the boiler return piping as close to the boiler as possible
and especially after any flow control or check valves in the space
heating return piping. The use of a union and a shut-off valve is
recommended. The use of a flow control or check valve is required to
prevent back flow through the water heater during operation of the
space heating system. Pipe and fittings between the boiler and
indirect-fired water heater should be ¾” diameter or larger.

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Water Connections continued-
CONNECT WATER BOILER SUPPLY PIPING
1. For a space heating system that utilizes ZONE VALVES, refer to
Figure 2. The indirect-fired water heater connection labeled
“FROM BOILER SUPPLY” should be piped to the boiler supply
piping. Mount the circulator making sure the flow arrow points
toward the water heater. The use of shut-off valves and unions
are recommended for future service convenience. The use of an
air separator and vent is recommended to eliminate air in the
system. Pipe and fittings between the boiler and indirect-fired
water heater must be ¾” diameter or larger.
CAUTION
Maximum boiler water supply temperature to the indirect
heat exchanger must not exceed 240°F (116°C).
Figure 2 - Water Boiler Piping with Zone Valves
2. For a space heating system that utilizes CIRCULATORS, refer to
Figure 3. The indirect-fired water heater connection labeled
“FROM BOILER SUPPLY” should be piped to the boiler supply
piping. Mount the circulator making sure the flow arrow points
toward the water heater. The use of shut-off valves and unions are
recommended for future service convenience. The use of an air
separator and vent is recommended to eliminate air in the system.
Pipe and fittings between the boiler and indirect-fired water heater
must be ¾” diameter or larger.

20
Water Connections continued-
Figure 3 - Water Boiler Piping with Circulators
CONNECT STEAM BOILER SUPPLY PIPING
Figure 4 represents a typical steam boiler connection diagram. Refer
to the boiler installation manual or contact the boiler manufacturer for
an appropriate piping diagram. The use of a union, shut-off valves,
and a drain valve is recommended for future service convenience.
The use of an in-line “Y”-style strainer is required to prevent
accumulation of sludge in the water heater’s coil.
Figure 4 -Typical Steam Boiler Connections (connections
available below the water line)