A.O. Smith XB-1000 User manual

XP BOILER
Instruction Manual
PRINTED IN THE U.S.A. 0711 320741-002
Thank you for buying this energy efcient boiler.
We appreciate your condence in our products.
MODELS: XB/XW
1000, 1300, 1700
2000, 2600, 3400
SERIES 100/101
INSTALLATION - OPERATION -
MAINTENANCE - LIMITED WARRANTY
25589 Highway 1
McBee, SC 29101
WARNING: If the information in these
instructions is not followed exactly, a fire
or explosion may result causing property
damage, personal injury or death.
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS:
Do not try to light any appliance.
Do not touch any electrical switch; do
not use any phone in your building.
Immediately call your gas supplier
from a neighbor’s phone. Follow the
gas supplier’s instructions.
If you cannot reach your gas supplier,
call the fire department.
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
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2
TABLE OF CONTENTS
TABLE OF CONTENTS.......................................................................... 2
SAFE INSTALLATION, USE AND SERVICE.......................................... 3
GENERAL SAFETY................................................................................ 4
INTRODUCTION.................................................................................... 5
Model Identication............................................................................ 5
Abbreviations Used ........................................................................... 5
Qualications ..................................................................................... 5
DIMENSIONS AND CAPACITY DATA.................................................... 6
FEATURES AND COMPONENTS ....................................................... 10
Component Description ................................................................... 12
CONTROL COMPONENTS ................................................................. 13
BOILER INSTALLATION CONSIDERATIONS ..................................... 15
Hydronic System ............................................................................. 15
Hot water boiler system - general water line connections ............... 16
GENERAL REQUIREMENTS .............................................................. 21
Location ........................................................................................... 21
Fresh air openings for conned spaces........................................... 23
VENTING.............................................................................................. 25
Vent Installation Considerations ...................................................... 25
Venting Supports ............................................................................. 27
CONDENSATE DISPOSAL.................................................................. 37
GAS SUPPLY CONNECTIONS ........................................................... 38
BOILER START UP AND OPERATIONS ............................................. 40
LIGHTING AND OPERATING INSTRUCTIONS .................................. 42
CONTROL SYSTEM ............................................................................ 45
Burner Control System .................................................................... 45
Burner control operation .................................................................. 46
General operational sequence ........................................................ 47
Local operator interface: display system ......................................... 49
Installation instructions (S7999B OI Display) .................................. 50
Starting up the S7999B OI Display.................................................. 51
Page Navigation .............................................................................. 51
TROUBLESHOOTING ......................................................................... 61
MAINTENANCE PROCEDURES......................................................... 76
Maintenance schedules................................................................... 76
General maintenance ...................................................................... 76
Burner maintenance ........................................................................ 77
Venting maintenance ....................................................................... 78
Heat exchanger maintenance.......................................................... 78
Handling ceramic ber materials ..................................................... 79
Replacement parts .......................................................................... 79
PIPING DIAGRAMS ............................................................................. 80
LIMITED WARRANTY.......................................................................... 82

3
The proper installation, use and servicing of this boiler is extremely important to your safety and the safety of others.
Many safety-related messages and instructions have been provided in this manual and on your boiler to warn you and others of a
potential injury hazard. Read and obey all safety messages and instructions throughout this manual. It is very important that the
meaning of each safety message is understood by you and others who install, use, or service this boiler.
DANGER
WARNING
CAUTION
CAUTION
DANGER indicates an imminently
hazardous situation which, if not avoided,
will result in injury or death.
This is the safety alert symbol. It is used to alert you to
potential personal injury hazards. Obey all safety
messages that follow this symbol to avoid possible
injury or death.
WARNING indicates a potentially hazardous
situation which, if not avoided, could result
in injury or death.
CAUTION indicates a potentially hazardous
situation which, if not avoided, could result in
minor or moderate injury.
CAUTION used without the safety alert
symbol indicates a potentially hazardous
situation which, if not avoided, could result in
property damage.
All safety messages will generally tell you about the type of hazard, what can happen if you do not follow the safety message, and
how to avoid the risk of injury.
The California Safe Drinking Water and Toxic Enforcement Act requires the Governor of California to publish a list of substances
known to the State of California to cause cancer, birth defects, or other reproductive harm, and requires businesses to warn of
potential exposure to such substances.
This product contains a chemical known to the State of California to cause cancer, birth defects, or other reproductive harm. This
boiler can cause low level exposure to some of the substances listed in the Act.
IMPORTANT DEFINITIONS
Gas Supplier: The Natural Gas or Propane Utility or service who supplies gas for utilization by the gas burning
appliances within this application. The gas supplier typically has responsibility for the inspection and code approval of
gas piping up to and including the Natural Gas meter or Propane storage tank of a building. Many gas suppliers also
offer service and inspection of appliances within the building.
SAFE INSTALLATION, USE AND SERVICE
APPROVALS

4
GROUNDING INSTRUCTIONS
This boiler must be grounded in accordance with the National
Electrical Code, Canadian Electrical Code and/or local codes.
Boiler is polarity sensitive; correct wiring is imperative for proper
operation.
This boiler must be connected to a grounded metal, permanent
wiring system, or an equipment grounding conductor must be
run with the circuit conductors and connected to the equipment
grounding terminal or lead on the boiler.
INLET WATER CONSIDERATIONS
Circulating water through the boiler and to the remote storage
tank (if applica ble) is accomplished by a pump on XW models
only. For hot water heating systems using the XB model, the
circulating pump is NOT provided on standard models (optional)
and must be eld installed.
CORRECT GAS
Make sure the gas on which the boiler will operate is the same as
that speci ed on the boiler rating plate. Do not install the boiler if
equipped for a different type of gas; con sult your supplier.
PRECAUTIONS
If the unit is exposed to the following, do not operate until all
corrective steps have been made by a qualied service agent:
1. Exposure to re.
2. If damaged.
3. Firing without water.
4. Sooting.
If the boiler has been exposed to ooding, it must be replaced.
LIQUEFIED PETROLEUM GAS MODELS
Boilers for propane or liqueed petroleum gas (LPG) are different
from natural gas models. A natural gas boiler will not function safely
on LP gas and no attempt should be made to convert a boiler from
natural gas to LP gas.
LP gas must be used with great caution. It is highly explosive
and heavier than air. It collects rst in the low areas making its
odor difcult to detect at nose level. If LP gas is present or even
suspected, do not attempt to nd the cause yourself. Leave
the building, leaving doors open to ventilate, then call your gas
supplier or service agent. Keep area clear until a service call
has been made.
At times you may not be able to smell an LP gas leak. One
cause is odor fade, which is a loss of the chemical odorant that
gives LP gas its distinctive smell. Another cause can be your
physical condition, such as having a cold or diminishing sense
of smell with age. For these reasons, the use of a propane gas
detector is recommended.
If you experience an out of gas situation, do not try to relight
appliances yourself. Call your local service agent. Only trained
LP professionals should conduct the required safety checks in
accordance with industry standards.
HIGH ALTITUDE INSTALLATIONS
Rated inputs are suitable up to 2000 feet (610 m) elevation. Consult
the factory for installation at altitudes over 2000 feet (610 m).
FIELD INSTALLED COMPONENTS
When installing the boiler, the follow ing compo nents must be
installed:
• Circulating Pump (Hyd ronic)
• Remote Temperature Sensor/Header Sensor
• Storage Tank (Temperature & Pressure Relief Valve)
GENERAL SAFETY

5
This Instruction Manual covers XP Boiler models XB/XW 1000,
1300, 1700, 2000, 2600, 3400 - Series 100/101. The instructions
and illustrations contained in this Instruction manual will provide
you with troubleshooting procedures to diagnose and repair
common problems and verify proper operation.
MODEL IDENTIFICATION
Check the rating plate afxed to the Boiler. The following
information describes the model number structure:
SERIES-100/101 DESIGNATION:
• XP = Extreme Performance
MODEL (APPLICATION):
• XB = Hydronic Heating Boiler
• XW = Domestic Hot Water Supply Boiler
SIZE:
• 1000 = 920,000 Btu/hr input
• 1300 = 1,300,000 Btu/hr input
• 1700 = 1,700,000 Btu/hr input
• 2000 = 2,000,000 Btu/hr input
• 2600 = 2,600,000 Btu/hr input
• 3400 = 3,400,000 Btu/hr input
FUEL:
N = Natural gas
P = Propane
NOTE:
XB models are equipped with 50 psi pressure relief valve. (pump
is optionally installed)
XW models are factory installed circulating pump (standard),
with 125 psi pressure relief valve.
XB models can be special ordered with a factory installed pump
and XW models can be special ordered without the factory
installed pump. These factory congurations can also be
changed in the eld by installing circulation pumps and changing
pressure relief valves to accommodate domestic and hydronic
hot water system requirements.
Properly installed and maintained, it should give you years of
trouble free service.
ABBREVIATIONS USED
Abbreviations found in this Instruction Manual include :
• ANSI - American National Standards Institute
• ASME - American Society of Mechanical Engineers
• NEC - National Electrical Code
• NFPA - National Fire Protection Association
• UL - Underwriters Laboratory
• CSA - Canadian Standards Association
• AHRI - Air-Conditioning, Heating and Refrigeration Institute
INTRODUCTION
QUALIFICATIONS
QUALIFIED INSTALLER OR SERVICE AGENCY
Installation and service of this boiler requires ability equivalent
to that of a Qualied Agency, as dened by ANSI below. In the
eld involved. Installation skills such as plumbing, air supply,
venting, gas supply and electrical supply are required in addition
to electrical testing skills when performing service.
ANSI Z21.13 - CSA 4.9: “Qualied Agency” - “Any individual,
rm, corporation or company that either in person or through
a representative is engaged in and is responsible for (a) the
installation, testing or replacement of gas piping or (b) the
connection, installation, testing, repair or servicing of appliances
and equipment; that is experienced in such work; that is familiar
with all precautions required; and that has complied with all the
requirements of the authority having jurisdiction.”
If you are not qualied (as dened by ANSI above) and licensed
or certied as required by the authority having jurisdiction
to perform a given task do not attempt to perform any of the
procedures described in this manual. If you do not understand
the instructions given in this manual do not attempt to perform
any procedures outlined in this manual.
This product requires a formal Start-Up by an authorized service/
start-up provider that has been approved by the manufacturer for
this specic product. Call 1-800-527-1953 to locate the nearest
authorized start-up provider and arrange a factory start-up.
Please provide as much notice as possible, preferably 2 weeks.
Please have the model and serial number ready when you call.
This start-up is required to activate the warranty and ensure safe,
efcient operation.
Warranty on this product is limited and could be void in the event
the unit is not installed per the instructions in this manual and/or
not started up by an authorized factory trained service/start-up
provider.

6
DIMENSIONS AND CAPACITY DATA
TABLE 1. ROUGH IN DIMENSIONS (SINGLE)
Models XB/XW-1000 XB/XW-1300 XB/XW-1700
Dimensions inches mm inches mm inches mm
Flue Outlet Diameter 6152 8152 8203
Air Intake Diameter 6152 6152 8203
Water Inlet 2 inch NPT 2 1/2 inch NPT
Water Outlet 2 inch NPT 2 1/2 inch NPT
Gas Inlet 2 inch NPT 2 inch NPT
A47 1199 49 1245 57 1448
B67 1702 68 1727 76 1930
C29 737 29 737 29 737
D37 940 38 965 37 940
E23 584 23 584 24 610
F9229 9229 9229
G34 864 34 864 34 864
H44 1118 45 1143 45 1143
J6152 6152 6152
K11 279 11 279 11 279
L12 305 11 279 12 305
TABLE 2. OPERATING CHARACTERISTICS
Models
(XB/XW)
Manifold Pressure Maximum Supply Pressure Minimum Supply Pressure
Type of Gas Inches W.C. kPa Inches W.C. kPa Inches W.C. kPa
1000, 1300, 1700
2000, 2600, 3400
Natural
Min Fire -0.2 to - 0.3 -0.05 to - 0.07
14.0 3.49 4.0 1.0
Max Fire -3.0 to -3.9 -0.75 to -0.97
Propane
Min Fire -0.1 to - 0.3 -0.025 to -0.07
14.0 3.49 4.0 2.0
Max Fire -3.6 to -4.9 -0.90 to -1.22
FIGURE 1. SINGLE HEAT EXCHANGER BOILER

7
TABLE 3. ROUGH IN DIMENSIONS (DOUBLE)
Models XB/XW-2000 XB/XW-2600 XB/XW-3400
Dimensions inches mm inches mm inches mm
Flue Outlet Diameter 8203 8203 10 254
Air Intake Diameter 8203 8203 10 254
Water Inlet 3 inch NPT 4 inch NPT
Water Outlet 3 inch NPT 4 inch NPT
Gas Inlet 2 inch NPT 3 inch NPT
A47 1194 49 1245 57 1448
B78 1981 80 2032 91 2311
C36 914 37 940 37 940
D22 559 22 559 22 559
E40 1016 41 1041 41 1041
F7178 6152 6152
G10 254 10 254 10 254
H4102 4102 4102
J20 508 19 483 19 483
K12 305 12 305 13 330
TABLE 4. RECOVERY CAPACITIES
Models Input Rating
(Btu/hr)
Output Rating
(Btu/hr)
Water
Flow
Temperature Rise - ΔT °F (°C)
40
(22)
60
(33)
70
(39)
80
(44)
90
(50)
100
(56)
120
(67)
140
(78)
XW-1000 920,000 854,680 GPH 2,593 1,728 1,482 1,296 1,152 1,037 864 741
LPH 9,815 6,543 5,608 4,907 4,362 3,926 3,272 2,804
XW-1300 1,300,000 1,207,700 GPH 3,664 2,442 2,094 1,832 1,628 1,465 1,221 1,047
LPH 13,868 9,246 7,925 6,934 6,164 5,547 4,623 3,962
XW-1700 1,700,000 1,579,300 GPH 4,791 3,194 2,738 2,395 2,129 1,916 1,597 1,369
LPH 18,136 12,090 10,363 9,068 8,060 7,254 6,045 5,182
XW-2000 2,000,000 1,858,000 GPH 5,636 3,758 3,221 2,818 2,505 2,255 1,879 1,610
LPH 21,336 14,224 12,192 10,668 9,483 8,534 7,112 6,096
XW-2600 2,600,000 2,415,400 GPH 7,327 4,885 4,187 3,664 3,257 2,931 2,442 2,094
LPH 27,737 18,491 15,850 13,868 12,327 11,095 9,246 7,925
XW-3400 3,400,000 3,158,600 GPH 9,582 6,388 5,475 4,791 4,259 3,833 3,194 2,738
LPH 36,271 24,181 20,726 18,136 16,121 14,508 12,090 10,363
FIGURE 2. DOUBLE HEAT EXCHANGER BOILER

8
MODELS
(XB/XW)
INPUT
MBH
GROSS
OUTPUT MBH
(NOTE 1)
NET I=B=R RATINGS WATER MBH
(NOTE 2)
MAX MIN
1000 920 100 856 744
1300 1300 130 1209 1051
1700 1700 170 1581 1375
2000 2000 100 1860 1617
2600 2600 130 2418 2103
3400 3400 212 3162 2750
RATINGS
TABLE 5. IBR RATINGS
Notes:
1. The ratings are based on standard test procedures prescribed by the United States Department of Energy.
2. Net I=B=R ratings are based on net installed radiation of sufcient quantity for the requirements of the building and nothing need
be added for normal piping and pickup. Ratings are based on a piping and pickup allowance of 1.15.
3. Ratings have been conrmed by the Hydronics Institute, Section of AHRI.
MODELS
(XB/XW)
SUPPLY VOLTAGE
(VOLTS)
FREQUENCY
(HZ)
CURRENT
(AMPS)
ELECTRICAL NOTES
1000 120 60 30 A dedicated, single phase, 30/60 amp circuit breaker
with a grounded neutral should be provided to supply
power to the boiler.
1300 120 60 30
1700 120 60 30
2000 120 60 60 A dedicated, single phase, 60/60 amp circuit breaker
with a grounded neutral should be provided to supply
power to the boiler.
2600 120 60 60
3400 120 60 60
ELECTRICAL REQUIREMENTS
TABLE 6. ELECTRICAL REQUIREMENTS

9
FLOW, HEAD AND TEMPERATURE RISE
TABLE 7. XB MODELS - FLOW, HEAD AND TEMPERATURE RISE
Models Input
(Btu/hr)
Output
(Btu/hr)
Water
Flow
Temperature Rise - ΔT °F Flow Rate
20 30 40 Maximum Minimum
XB-1000 920,000 855,600
GPM 86 56 43 86 43
LPM 325 211 162 325 162
ΔP FT 26 12 726 7
ΔP M 7.9 3.7 2.1 7.9 2.1
XB-1300 1,300,000 1,209,000
GPM 120 80 60 120 60
LPM 453 302 226 453 226
ΔP FT 32.5 15 832.5 8
ΔP M 9.9 4.6 2.4 9.9 2.4
XB-1700 1,700,000 1,581,000
GPM 156 104 78 156 78
LPM 592 395 296 592 296
ΔP FT 35 14 835 8
ΔP M 10.7 4.3 2.4 10.7 2.4
XB-2000 2,000,000 1,860,000
GPM 184 123 92 184 92
LPM 696 464 348 696 348
ΔP FT 26 12 726 7
ΔP M 7.9 3.7 2.1 7.9 2.1
XB-2600 2,600,000 2,418,000
GPM 239 159 120 239 120
LPM 905 604 453 905 453
ΔP FT 32.5 15 832.5 8
ΔP M 9.9 4.6 2.4 9.9 2.4
XB-3400 3,400,000 3,162,000
GPM 313 209 156 313 156
LPM 1184 789 592 1184 592
ΔP FT 35 14 835 8
ΔP M 10.7 4.3 2.4 10.7 2.4
Note: Head Loss shown is through the boiler only and allows for no additional piping.

10
FEATURES AND COMPONENTS
FIGURE 3. SINGLE HEAT EXCHANGER BOILER COMPONENTS

11
FIGURE 4. DOUBLE HEAT EXCHANGER BOILER COMPONENTS

12
COMPONENT DESCRIPTION
1. Front access door:
Provides access to the gas train, burner controllers and the heat
exchanger.
2. Air Filter Box:
Allows for the connection of the PVC air intake pipe to the boiler
through a standard PVC adapter. It uses a lter to prevent dust
and debris from entering the boiler.
3. Automatic air vents:
Designed to remove trapped air from the heat exchanger coils.
4. Blowers:
The blowers pull in air and gas through the venturis. Air and gas
mix inside the venturi and are pushed into the burners, where
they burn inside the combustion chamber.
5. Boiler inlet temperature sensors
These sensors monitor system return water temperature.
6. Boiler outlet temperature sensors/High Limits
These sensors monitor boiler outlet water temperature. The boiler
modulates based on the Lead Lag Sensor connected to the tank.
7. Burners
Made with metal ber and stainless steel construction, the
burners use pre-mixed air and gas and provide a wide range of
ring rates.
8. Condensate Trap
Disposes the condensate produced from heat exchanger and
houses a switch that detects in case of blockage.
9. Control modules
The control modules respond to internal and external signals and
control the blowers, gas valves, and pumps to meet the heating
demand.
10. Touch Screen Display
Digital controls with touch screen technology and full color
display.
11. Sight glass
The quartz sight glass provides a view of the ame for inspection
purposes.
12. Flame sensors
Used by the control module to detect the presence of burner
ame.
13. Flap valves
Prevents recirculation of ue products when only one burner is
running.
14. Flue gas sensors (not visible)
These sensors monitor the ue gas exit temperature. The control
modules will modulate and shut down the boiler if the ue gas
temperature gets too hot. This protects the ue pipe from
overheating.
15. Flue pipe adapter (not visible)
Allows for the connection of the PVC vent pipe system to the
boiler.
16. Gas shutoff valves (Internal unit)
Manual valves used to isolate the gas valves from the burners.
17. Main gas shutoff valve (External unit)
Manual valve used to isolate the boiler from the gas supply.
18. Automatic modulating gas valve
The gas valve with the addition of venturi and blower are used for
modulating premix appliances.
19. Heat exchanger access covers
Allows access to the combustion side of the heat exchanger
coils.
20. High gas pressure switch
Switch provided to detect excessive supply gas pressure.
21. Spark Igniter
Provides direct spark for igniting the burners.
22. Boiler power supply terminals (not visible)
The main power to the boiler is supplied through the terminals
housed inside the high voltage junction box.
23. Low gas pressure switch
Switch provided to detect low gas supply pressure.
24. High voltage connection box
This box has terminals for connecting the main power supply
(120V) to the boiler and outputs power supply (120V) for the
pumps from the boiler control. This box has terminals for low
voltage devices such as condensate trap and ow switch.
25. Sensors/Communication Box
Connects sensors to tank sensor/header sensor and external
connections to building managements systems through MODBUS.
26. Low water cutoff board and sensor probe (LWCO)
Device used to ensure adequate water is supplied to the boiler.
In the event of inadequate water levels, LWCO will ensure boiler
shut down. LWCO board is connected to the electronic panel,
whereas the sensor probe is connected to the heat exchanger.
27. Main power supply switch
Turns 120 VAC ON/OFF to the boiler.
28. Pump relay
The pump relays are used tfor providing power to the XW Boiler
models.
29. Pressure relief valve
Protects the heat exchangers from an over pressure condition.
The relief valve will be set at particular PSI, depending on models.
30. Reset switch (optional) (not visible)
Reset switch for the low water cutoff.
31. Stainless steel heat exchangers
Allows system water to ow through specially designed coils.
32. Venturi
The venturi is a gas/air mixing unit that allows modulation of a
premix burner with constant gas/air ratio.
33. Water inlet
Water connection that return water from the system to the heat
exchangers.
34. Water outlets
A NPT water connection that supplies hot water to the system.
35. Enable/Disable Switch
This is an emergency boiler turn off switch which disconnects
the interlock voltage to the control board, hence turning off the
power supply to the gas valves. Do not use this switch for
turning off the boiler, this should be done from the touch
screen display, using the Operational Switch on the Lead
Lag screen.
36. Vent outlet
Provides an outlet for combustion gases to outdoor.

13
FIGURE 7. LOW/HIGH GAS PRESSURE SWITCH
GAS VALVE
The gas valve is a normally closed servo regulated gas valve.
The valve opens only when energized by the burner control and
closes when the power is removed. The burner control supplies
24 volts to the gas valve during operation.
FIGURE 8. GAS VALVE
WATER FLOW SWITCH
The water ow switch activates when sufcient water ow has
been established. Switch will not close when water ow is not
present.
FIGURE 9. WATER FLOW SWITCH
THE CONTROL SYSTEM
The R7910A1138 is a burner control system that provides heat
control, ame supervision, circulation pump control, fan control,
boiler control sequencing, and electric ignition function. It will
also provide status and error reporting.
FIGURE 5. BURNER CONTROL SYSTEM
SPARK IGNITER
The spark igniter is a device that ignites the main burner. When
power is supplied to the igniter electrode, an electric arc is
created between the electrode and the ground terminal which
ignites the main burner.
FIGURE 6. SPARK IGNITER
LOW/HIGH GAS PRESSURE SWITCH
This XP boiler is equipped with a low gas pressure switch which
meets the CSD-1 code requirements.
The Low Gas Pressure Switch is normally open and remains
open unless the pressure falls below the preset pressure.
The High Gas Pressure Switch is normally closed and is used to
detect excessive gas pressure.
CONTROL COMPONENTS

14
FLAME SENSOR
Each burner is equipped with a ame sensor to detect the
presence of the burner ames at high and low re conditions. If
no ame is sensed, the gas valve will close automatically. The
voltage sensed by the ame sensor will also be displayed on the
Burner Screen.
FIGURE 10. FLAME SENSOR
WATER TEMPERATURE LIMIT CONTROLS
The “XB/XW” models incorporate an outlet water sensor having
dual sensors, that are factory set at 210°F (99°C).
MAIN POWER SUPPLY SWITCH
The main power supply switch is a padlockable switch. This switch
pro vides 120V from the power supply to the boiler.
This switch needs to be turned off when servicing the boiler.
Note: The Enable/Disable Switch on the front of the boiler
does not interrupt electrical power to the boiler.
FIGURE 11. MAIN POWER SUPPLY SWITCH
WATER TEMPERATURE SENSORS
FIGURE 12. WATER TEMPERATURE SENSORS
Temperature sensors are threaded immersion probes.
Temperature probes have embedded temperature sensors
(thermistors). The boiler’s control system monitors these sensors
to determine water temperature at various points in the system.
INLET AND OUTLET TEMPERATURE SENSORS
All models have two inlet and two outlet temperature sensors
for each heat exchanger, factory installed to monitor the water
temperature entering and leaving the boiler. The Inlet Probe is
a temperature sensor only and has two leads. The Outlet probe
also contains the manual reset high temperature limit switch
and has four leads. The control system displays the Inlet and
Outlet water temperatures sensed from these two sensors on the
default Temperatures screen.
REMOTE SENSORS
All models are supplied from the factory with a remote sensor.
The remote sensor is used to control system water temperature
for a single boiler in a domestic hot water storage tank or in the
return line from a primary/secondary hydronic heating system.
The boiler will modulate its ring rate in response to the
actual system temperature and load conditions. The control
system displays the temperature sensed from the remote sensor
as the “Lead Lag” temperature on the default Temperatures
screen.
LOW WATER CUTOFF DEVICE (LWCO)
Low water cutoff device is normally a closed switch that opens
when water drops below a preset level. Each model is equipped
with a factory installed LWCO. LWCO board is connected to the
electronic panel, whereas the sensor probe is connected to the
heat exchanger.
FIGURE 13. LWCO BOARD AND PROBE

15
GENERAL
If the system is to be lled with water for testing or other purposes
during cold weather and before actual operation, care must be taken
to prevent freezing of water in the system. Failure to do so may cause
the water in the system to freeze with resulting damage to the system.
Damage due to freezing is not covered by the warranty.
Figure 78 on Page 80 shows a typical primary, secondary piping
method. This is the preferred piping method for most stainless steel
boilers. Other piping methods, however, may provide good system
operation. A prime concern when designing heating systems is the
maintenance of proper ow through the unit during boiler operation.
The secondary pump should be sized per the recommended ow
rate of the boiler, see Dimension and Capacity Data section in this
manual.
Before locating the boiler:
1. Check for nearby connection to:
• System water piping
• Venting connections
• Gas supply piping
• Electrical power
2. Locate the boiler so that if water connections should leak,
water damage will not occur. When such locations cannot
be avoided, it is recommended that a suitable drain pan,
adequately drained, be installed under the appliance.
The pan must not restrict combustion air ow. Under no
circumstances is the manufacturer to be held responsible
for water damage in connection with this appliance, or any
of its components.
3. Check area around the boiler. Remove any combustible
materials, gasoline and other ammable liquids.
4. Make sure the gas control system components are protected
from dripping or spraying water or rain during operation or
service.
5. If a new boiler will replace an existing boiler, check for and
correct system problems, such as:
• System leaks causing oxygen corrosion or heat
exchanger cracks from hard water deposits.
• Lack of freeze protection in boiler water causing system
and boiler to freeze and leak.
HYDRONIC SYSTEM
The following is a brief description of the equipment required
for the installations noted in this manual. All installations must
comply with local code.
WATER SUPPLY LINE
These boilers can be used only in a forced circulation hot water
heating system. Since most forced circulation systems will be of
the closed type, install the water supply line as shown on piping
diagram.
Fast lling of large pipe, old radiator installations and pressure
purging of series loop systems (where high pressures are not
available) requires bypassing of the pressure reducing valve.
Gener ally, pressure purging is not possible with a well pump
system. High point air venting is essential.
If the system is of the open type, a pressure reducing valve will not
be required as the water supply to the system will be controlled by
a manu ally operated valve. An overhead surge tank is required. A
minimum pressure of 15 psi (100 kPa) must be maintained on the
boiler at all times to ensure avoidance of potential damage to the
boiler which may not be covered by the warranty.
EXPANSION TANK
If the system is of the closed type, install an expansion tank. The
sizing of the expansion tank for a closed system is very important and
is directly related to the total water volume of the system.
An air separator as shown in the piping diagrams is recommended
especially for modern commercial hydronic systems. See Figure 78
on Page 80.
VENT VALVES
It is recommended that automatic, loose key or screw-driver type
vent valves be installed at each convector or radiator.
SYSTEM HEADERS
Split systems with individual supply and return lines from the
boiler room should normally have this piping connected to
supply and return manifold headers near the boiler. To achieve
good water distribution with maximum pressure drop for sever al
circuits, manifolds should be larger than system mains.
The circuits should be spaced on the heater at a minimum of 3”
(76 mm) center to center. Install a balancing cock in each return
line.
Manifold headers are recommended for split systems with
or without zone valves and also those installations with zone
circulators. If the system is to be split at remote points, good
practice requires special attention be given to main pipe sizing to
allow balancing of water ow.
CHECK VALVES
Check valves must be installed to isolate each boiler in
installations where multiple boilers/pumps are installed in the
same zone.
COOLING PIPING
When the boiler is used in conjunction with a refrigeration system
it must be installed so that the chilled medium is piped in parallel
with the boiler. Appropriate ow control valves, manual or
motorized, must be provided to prevent the chilled medium from
entering the boiler.
If the boiler is connected to chilled water piping or its heating coils
are exposed to refrigerated air, the boiler piping system must be
equipped with ow valves or other automatic means to prevent
gravity circulation through the boiler during the cooling cycle.
Primary/secondary pumping of both the chiller(s) and the boiler(s) is
an excellent winter-summer change-over method, because cooling
ow rates are so much more than heating ow rates. In this way each
system (heating or cooling) is circulated independently.
BOILER INSTALLATION CONSIDERATIONS

16
CIRCULATING PUMP
A circulating pump is used when a system requires a circulating
loop or there is a storage tank used in conjunction with the boiler.
Install in accordance with the current edition of the National
Electrical Code, NFPA 70 or the Canadian Electrical Code,
CSA C22.1. All bronze circulating pumps are recommended
for use with commercial boilers. Some circulating pumps are
manufactured with sealed bearings and do not require further
lubrication. Some circulating pumps must be periodically oiled.
Refer to the pump manufacturer’s instructions for lubrication
requirements.
XB HYDRONIC BOILERS: The circulating pump is not provided
on standard models (optional) and must be obtained and installed
in the eld.
XW HOT WATER BOILERS: The circulating pump is integral to
the XW models. This pump has been lubricated at the factory,
and future lubrication should be in accordance with the motor
manufacturer’s instructions provided as a supplement to this
manual.
PRIMARY SYSTEM CONTROL
All XP boiler installations require a “Primary System Control” that
senses and reacts to water temperature inside the storage tank
on domestic water applications or in the return line on primary/
secondary hydronic heating systems. The Primary System
Control will activate and deactivate boiler heating cycles based
on its setpoint and current system water temperature. There are
three suitable methods to congure a Primary System Control.
One of these three methods must be used.
1. The Primary System Control can be the boiler’s
control system working with the factory supplied Header
Sensor, installed inside the storage tank on domestic water
applications or in the return line on primary/secondary
hydronic heating systems.
2. Alternatively, the Burner Control system can be used
as a Primary System Control. It will also provide boiler status
and error reporting. Multiple boilers can be joined together
to heat a system instead of a single, larger burner or boiler.
Using boilers in parallel is more efcient, costs less, reduces
emissions, improves load control, and is more exible than
the traditional large boiler.
3. MB2 and COM2 ports can be used for Building
Management Systems.
INTERNAL CONTAMINANTS
The hydronic system must be internally cleaned and ushed
after a new or replacement boiler has been installed, to remove
contaminants that may have accumulated during installation.
This is extremely important when a replacement boiler is installed
into an existing system where Stop Leak or other boiler additives
have been used.
Failure to clean and ush the system can produce acid
concentrations that become corrosive, and leads to heat
exchanger failure.
All hot water heating systems should be completely ushed with
a grease removing solution to assure trouble-free opera tion. Pipe
joint compounds, soldering paste, grease on tubing and pipe all
tend to contaminate a system
Failure to ush contaminants from a system can cause solids
to form on the inside of boiler exchangers, create excessive
blockage of water circulation, deterioration of the pump seals
and impellers.
HOT WATER BOILER SYSTEM - GENERAL WATER
LINE CONNECTIONS
Piping diagrams will serve to provide the installer with a
reference for the materials and methods of piping necessary for
installation. It is essential that all water piping be installed and
connected as shown on the diagrams. Check the diagrams to
be used thoroughly before starting installation to avoid possible
errors and to minimize time and material cost. It is essential that
all water piping be installed and connected as shown on the
diagrams. See Figure 78 on Page 80 and Figure 79 on Page 81.
CLOSED WATER SYSTEMS
Water supply systems may, because of code requirements
or such conditions as high line pressure, among others, have
installed devices such as pressure reducing valves, check
valves, and back ow preventers. Devices such as these cause
the water system to be a closed system.
THERMAL EXPANSION
As water is heated, it expands (thermal expansion). In a closed
system the volume of water will increase when it is heated. As the
volume of water increases there will be a corresponding increase
in water pressure due to thermal expansion. Thermal expansion
can cause premature failure (leakage). This type of failure is not
covered under the limited warranty. Thermal expansion can also
cause intermittent Temperature-Pressure Relief Valve operation:
water discharged from the valve due to excessive pressure build
up. This condition is not covered under the limited warranty.
The Temperature-Pressure Relief Valve is not intended for the
constant relief of thermal expansion.
A properly sized thermal expansion tank must be installed on
all closed systems to control the harmful effects of thermal
expansion. Contact a local plumbing service agency to have a
thermal expansion tank installed.
PRESSURE RELIEF VALVE
An ASME rated pressure relief valve is furnished with the boiler.
A tting for the relief valve is provided in the top of the boiler.
Never operate the heating elements without being certain the
boiler is lled with water and a properly sized pressure relief
valve is installed in the relief valve opening provided.
The pressure rating of the relief valve should be equal to or less
than the rated pressure capacity of any component in the system
including the boiler. Should the valve need to be replaced, call
the toll free phone number listed on the back of this manual for
further technical assistance

17
A discharge pipe from the relief valve should terminate at an
adequate oor drain. Do not thread, plug, or cap the end of
drain line.
The Discharge Pipe:
• Shall not be smaller in size than the outlet pipe size of the
valve, or have any reducing couplings or other restrictions.
• Shall not be plugged or blocked.
• Shall not be exposed to freezing temperatures.
• Shall be of material listed for hot water distribution.
• Shall be installed so as to allow complete drainage of both
the relief valve and the discharge pipe.
• Must terminate a maximum of six inches above a oor
drain or external to the building. In cold climates, it is
recommended that the discharge pipe be terminated at an
adequate drain inside the building.
• Shall not have any valve or other obstruction between the
relief valve and the drain.
Once the boiler is installed and lled with water and the system
is pressurized, manually test the operation of the pressure relief
valve. See the Maintenance Procedures section of this manual
for instructions.
Your local code authority may have other specic safety relief
valve requirements not covered below. If any pressure relief
valve is re placed, the replace ment valve must com ply with the
current version of the ASME Boiler and Pressure Vessel Code,
Section IV (“HEATING BOILERS”).
XB HYDRONIC BOILERS, are shipped with a 50 psi (345 kPa)
pressure relief valve. This relief valve must be in stalled in the
water outlet as near to the boiler as possi ble.
XW HOT WATER BOILERS, are shipped with a 125 psi (860
kPa) pressure relief valve that must be in stalled in the water out-
let as near to the boil er as possi ble.
This ASME-rated valve has a discharge capacity that exceeds
maximum boiler input rating and a pres sure rating that does not
exceed maxi mum working pres sure shown on boiler rating plate.
In addition, a CSA design-certied and ASME-rated tempera ture
and pressure (T&P) relief valve must be installed on each and
every water storage tank in hot water supply system. The T&P
relief valve must comply with appli cable construction provisions
of Standard for Relief Valves for Hot Water Supply Systems, ANSI
Z21.22 or CSA 4.4. T&P re lief valve must be of automatic reset
type and not embody a single-use type fusible plug, cartridge or
linkage.
T&P relief valve should have a temperature rating of 210°F
(99°C), a pressure rating not exceeding lowest rated working
pressure of any system compo nent, and a discharge capacity
exceeding total input of water boilers supply ing water to storage
tank.
Locate the T&P relief valve (a) in the top of the tank, or (b) in
the side of the tank on a centerline within the upper 6 inches
(152 mm) of the top of the tank, see Figure 78 and Figure 79.
The tapping should be threaded in accordance with the current
edition of the Standard for Pipe Threads, General Purpose
(inch), ANSI/A SME B1.20.1. The location of, or in tended location
for, the T&P relief valve should be readily accessible for servicing
or replacement.
GAS CONNECTIONS
Make sure the gas on which boiler is to operate is same as that
specied on the rating plate. Do not install boiler if equipped for a
different type of gas. Consult your gas supplier.
This boiler is not intended to operate at gas supply pressure
other than shown on the rating plate. A lock-up or positive shut-
off type regulator must be installed in gas supply line. For proper
gas regulation the lock-up style regulators must be installed no
closer than a minimum of 3 feet from the boiler and a maximum
of 8 feet away from the boiler. Exposure to higher gas supply
pressure may cause damage to gas valves which can result in
re or explosion. If overpressure has occurred such as through
improper testing of gas lines or emergency malfunction of supply
system, the gas valves must be checked for safe operation.
Make sure that the outside vents on supply regulators and the
safety vent valves are protected against blockage. These are
parts of the gas supply system, not boiler. Vent blockage may
occur during ice build-up or snowstorms.
The boiler must be isolated from the gas supply piping system by
closing its main manual gas shut off valve during any pressure
testing of the gas supply piping system at test pressures equal
to or less than 1/2 psig.
Disconnect the boiler and its main manual gas shut-off valve
from the gas supply piping during any pressure testing of the
gas supply system over 1/2 psig. The gas supply line must be
capped when not connected to the boiler.
CAUTION
• Pressure Relief Valve discharge pipe must
terminate at adequate drain.
Water Damage Hazard
Explosion Hazard
Relief Valve must comply with
ASME code.
Properly sized Relief Valve must
be installed in opening provided.
Can result in overheating and
excessive tank pressure.
Can cause serious injury or death.

18
TABLE 8.
SINGLE UNIT INSTALLATION, SUGGESTED GAS PIPE
SIZING. MAXIMUM EQUIVALENT PIPE LENGTH (IN FEET).
BTU
Input
2” 2-1/2” 3” 4”
Nat Pro Nat Pro Nat Pro Nat Pro
920,000 70 150 175 ----- ----- ----- ----- -----
1,300,000 40 100 100 200 ----- ----- ----- -----
1,700,000 20 60 70 150 200 ----- ----- -----
2,000,000 20 50 50 100 150 ----- ----- -----
2,600,000 10 30 30 70 90 200 ----- -----
3,400,000 ----- ----- 20 40 50 125 200 -----
Natural gas 1000 Btu/ft^3, 0.60 specic gravity @ 0.3 in. w.c. pressure drop.
Propane gas 2500 Btu/ft^3, 1.50 specic gravity @ 0.3 in. w.c. pressure drop.
TABLE 9.
SINGLE UNIT INSTALLATION, SUGGESTED GAS PIPE
SIZING. MAXIMUM EQUIVALENT PIPE LENGTH (IN FEET).
BTU
Input
2” 2-1/2” 3” 4”
Nat Pro Nat Pro Nat Pro Nat Pro
920,000 125 200 200 ----- ----- ----- ----- -----
1,300,000 80 175 175 ----- ----- ----- ----- -----
1,700,000 40 100 100 ----- ----- ----- ----- -----
2,000,000 30 80 80 200 200 ----- ----- -----
2,600,000 20 50 50 125 150 ----- ----- -----
3,400,000 10 30 30 70 90 200 ----- -----
Natural gas 1000 Btu/ft^3, 0.63 specic gravity @ 0.5 in. w.c. pressure drop.
Propane gas 2500 Btu/ft^3, 1.50 specic gravity @ 0.5 in. w.c. pressure drop.
CORROSIVE MATERIALS AND CONTAMINATION
SOURCES
Products to avoid:
• Spray cans containing chloro/uorocarbons
• Permanent wave solutions
• Chlorinated waxes/cleaners
• Chlorine-based swimming pool chemicals
• Calcium chloride used for thawing
• Sodium chloride used for water softening
• Refrigerant leaks
• Paint or varnish removers
• Hydrochloric acid/muriatic acid
• Cements and glues
• Antistatic fabric softeners used in clothes dryers
• Chlorine-type bleaches, detergents, and cleaning
solvents found in household laundry rooms
• Adhesives used to fasten building products and other
similar products
Areas likely to have contaminants:
• Dry cleaning/laundry areas and establishments
• Swimming pools
• Metal fabrication plants
• Beauty shops
• Refrigeration repair shops
• Photo processing plants
It is important to guard against gas valve fouling from
contaminants in the gas ways. Such fouling may cause improper
operation, re or explosion. If copper supply lines are used they
must be approved for gas service.
When local codes require a main manual shut-off valve outside
the boiler jacket, a suitable main manual shut-off valve must be
installed in a location complying with those codes.
Before attaching gas line be sure that all gas pipe is clean
on inside. To trap any dirt or foreign material in the gas supply
line, a drip leg (or sediment trap) must be incorporated in piping.
The drip leg must be readily accessible and not subject to
freezing conditions. Install in accordance with recommendations
of serving gas supplier. Refer to the current edition of the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and
Propane Installation Code, CAN/CSA B149.1
Size of gas supply piping may be larger than heater connection
on installations where a signicant run of piping is required.
To prevent damage, care must be taken not to apply too much
torque when attaching gas supply pipe to boiler gas inlet. When
installing and tightening gas piping use a second wrench to hold
the gas valve to keep the valve from turning. To prevent damage
to the gas valve do not use pipe wrench on the valve body.
Fittings and unions in gas line must be of metal to metal type.
Apply joint compounds (pipe dope) sparingly and only to the
male threads of pipe joints. Do not apply compound to the rst
two threads. Use compounds resistant to the action of liqueed
petroleum gases. The boiler and its gas connection must be leak
tested before placing the boiler in operation.
GAS SUPPLY LINE SIZING
The gas piping installation must be capable of supplying the
maximum probable gas demand without excessive pressure loss.
Depending on local practices, the ALLOWABLE PRESSURE
LOSS between the gas meter, or service regulator and each
appliance is generally 0.3 or 0.5 inches of water column (0.075
or 0.124 kPa).
For single boiler installation, refer to Table 8 and Table 9 to size
iron pipe or equivalent gas supply line size to be used with single
unit.
For multiple boiler installation or installations of a single boiler
with other gas appliances, please refer to Table 10 and Table 11
on Page 20 to size iron pipe or equivalent gas supply line. These
tables are taken from the current edition of the National Fuel Gas
Code, ANSI Z223.1/NFPA 54 or the Natural Gas and Propane
Installation Code, CAN/CSA B149.1.
• Table 10 is based on a pressure drop of 0.5 inches water
column (0.124 kPa), and a gas with a specic gravity of
0.60 and a heating value of 1,000 BTU/ft3, approximately
that of Natural Gas.
• Table 11 is based on a pressure drop of 0.5 inches water
column (0.124 kPa), and a gas with a specic gravity of
1.53 and a heating value of 2,500 BTU/ft3, approximately
that of Propane Gas.
Where it is necessary to use more than the average number of
ttings (i.e., elbows, tees and valves in gas supply line) use a
pipe larger than specied to compensate for increased pressure
drop.
Table 8 and Table 9 shows the maximum equivalent gas pipe
length for a single unit installation. It does not take into account
other appliances that may be connected to the gas line.
For installation of multiple units, or instances where several
appliances are connected to the same line, use Table 10 and
Table 11 for proper sizing.

19
• Auto body shops
• Plastic manufacturing plants
• Furniture renishing areas and establishments
• New building construction
• Remodeling areas
Common household products, pool and laundry products may
contain uorine or chlorine compounds. When these chemicals
come in contact with the boiler, they react and can form strong
acids. The acid can spoil the boiler wall, causing serious damage
and may result in ue gas spillage or boiler water leakage into
the building.
If the above mentioned contaminants and corrosive materials
chemicals are present near the location of the boiler, make sure
to remove the boiler permanently or relocate air inlet and vent
terminations to other areas.
FIELD WIRING
120 VAC POWER SUPPLY WIRING
A dedicated, single phase, 30-60 amp (refer to Table 6 on Page
8) circuit breaker with a grounded neutral should be provided to
supply power to the boilers. Use #10 AWG wire for the 120 VAC
power supply to the boiler. All 120 VAC power supply connections
must be made as shown in Figure 14. These connections
should be made at the rear of the unit where a wiring junction
box is provided. Field installed power supply wiring to the boiler
should be installed in conduit. This conduit and wiring should
be separate from any other conduit/wiring to guard against EMI
(electromagnetic interference).
POWER SUPPLY CHECK
To reduce the possibility of electrical interference with the boiler’s
control system the power supply voltage, polarity and ground must
be checked. Using an AC volt meter check the 120 VAC power
supply wiring from the breaker prior to making power supply
connections at the boiler. Conrm the power supply voltage &
polarity are correct and that an adequate ground connection is
present by performing the three voltage tests below. See Figure
14 for wiring references.
Conrm RMS voltage between:
• H and GND = 108 VAC minimum, 132 VAC maximum.
• N and H = 108 VAC minimum, 132 VAC maximum.
• N and GND = < 1 VAC maximum.
FIGURE 14. FIELD WIRING
LOW VOLTAGE CONTROL WIRING
1. Header Terminals: In case of Hydronic Boilers, the header
terminals are connected to the hydronic loop header sensor.
Whereas in case of Hot water Boilers the header terminals
are connected to the tank sensor where the temperature can
be sensed. See Figure 15.
2. Outdoor Terminals: In case of Hydronic Boilers, they are
connected to the outdoor sensors. But in case of Hot water
Boilers, they are not connected. See Figure 15. The outdoor
sensors must be mounted with cable inlet facing down
as shown in Figure 16. The maximum length of the wire
connecting from the boiler to the outdoor sensor must be no
more than 50 feet.
3. MB2 and COM2 terminals are meant for building
management systems.
All low voltage control wiring connections must be made as
shown in Figure 14. These connections should be made at the
rear of the unit where a wiring junction box is provided. Field
installed wiring inside 1/2 inch conduit is installed between the
junction box on the back of the boiler and the temperature probe
and/or eld supplied external control being used. This conduit
and wiring should be separate from any other conduit/wiring to
guard against EMI (electromagnetic interference).
The outdoor sensor must be mounted in a shaded location, to
avoid direct sunlight. It must be atleast 3 feet away from any
exhaust, dryer, bathroom or other building vents. It must be
located on the north side of th building, above the expected snow
line where ice and debris cannot cover it.
FIGURE 15. LOW VOLTAGE CONTROL WIRING
FIGURE 16. OUTDOOR SENSOR

20
TABLE 10. SUGGESTED PIPE SIZE FOR MULTIPLE GAS APPLIANCES (NATURAL GAS)
Nominal Maximum Capacity of Pipe in BTU/hr and kW for Gas Pressures of 14 in. W.C. (0.5 psi) or Less and Iron Pipe a Pressure Drop of 0.5 in. W.C. (based on 0.60 Specic Gravity Gas w/Heating Value of 1,000 BTU’s/Ft3) Size Length of Pipe in Feet (Meters) (Inches) 10 (3.05) 20 (6.1) 30 (9.14) 40 (12.19) 50 (15.24) 60 (18.29) 70 (21.34) 80 (24.38) 90 (27.43) 100 (30.48) 125 (38.1) 150 175 200 1 1/2 BTU/hr 2,100,000 1,460,000 1,180,000 990,000 900,000 810,000 750,000 690,000 650,000 620,000 550,000 500,000 460,000 — kW 615 428 346 290 264 237 220 202 190 182 161 146 135 — 2 BTU/hr 3,950,000 2,750,000 2,200,000 1,900,000 1,680,000 1,520,000 1,400,000 1,300,000 1,220,000 1,150,000 1,020,000 950,000 850,000 800,000 kW 1,157 805 644 556 492 445 410 381 357 337 299 278 249 234 2 1/2 BTU/hr 6,300,000 4,350,000 3,520,000 3,000,000 2,650,000 2,400,000 2,250,000 2,050,000 1,950,000 1,850,000 1,650,000 1,500,000 1,370,000 1,280,000 kW 1,845 1,274 1,031 879 776 703 659 600 571 542 483 439 401 375 3 BTU/hr 11,000,000 7,700,000 6,250,000 5,300,000 4,750,000 4,300,000 3,900,000 3,700,000 3,450,000 3,250,000 2,950,000 2,650,000 2,450,000 2,280,000 kW 3,222 2,255 1,830 1,552 1,391 1,259 1,142 1,084 1,010 952 864 776 718 668 4 BTU/hr 23,000,000 15,800,000 12,800,000 10,900,000 9,700,000 8,800,000 8,100,000 7,500,000 7,200,000 6,700,000 6,000,000 5,500,000 5,000,000 4,600,000 kW 6,736 4,627 3,749 3,192 2,841 2,577 2,372 2,197 2,109 1,962 1,757 1,611 1,464 1,347
TABLE 11. SUGGESTED PIPE SIZE FOR MULTIPLE GAS APPLIANCES (PROPANE GAS)
Nominal Maximum Capacity of Pipe in BTU/hr and kW for Gas Pressures of 14 in. W.C. (0.5 psi) or Less and Iron Pipe a Pressure Drop of 0.5 in. W.C. (based on 0.60 Specic Gravity Gas w/Heating Value of 1,000 BTU’s/Ft3) Size Length of Pipe in Feet (Meters) (Inches) 10 (3.05) 20 (6.1) 30 (9.14) 40 (12.19) 50 (15.24) 60 (18.29) 70 (21.34) 80 (24.38) 90 (27.43) 100 (30.48) 125 (38.1) 150 175 200 1 1/2 BTU/hr 3,276,000 2,277,600 1,840,800 1,544,400 1,404,000 1,263,600 1,170,000 1,076,400 1,014,000 967,200 858,000 780,000 717,600 670,800 kW 959 667 539 452 411 370 343 315 297 283 251 228 210 196 2 BTU/hr 6,162,000 4,290,000 3,432,000 2,964,000 2,620,800 2,371,200 2,184,000 2,028,000 1,903,200 1,794,000 1,591,200 1,482,000 1,326,000 1,248,000 kW 1,805 1,256 1,005 868 768 694 640 594 557 525 466 434 388 366 2 1/2 BTU/hr 9,828,000 6,786,000 5,491,200 4,680,000 4,134,000 3,744,000 3,510,000 3,198,000 3,042,000 2,886,000 2,574,000 2,340,000 2,137,200 1,999,800 kW 2,878 1,987 1,608 1,371 1,211 1,097 1,028 937 891 845 754 685 626 585 3 BTU/hr 17,160,000 12,012,000 9,750,000 8,268,000 7,410,000 6,708,000 6,084,000 5,772,000 5,382,000 5,070,000 4,602,000 4,134,000 3,822,000 3,556,800 kW 5,026 3,518 2,856 2,421 2,170 1,965 1,782 1,690 1,576 1,485 1,348 1,211 1,119 1,042 4 BTU/hr 35,880,000 24,648,000 19,968,000 17,004,000 15,132,000 13,728,000 12,636,000 11,700,000 11,232,000 10,452,000 9,360,000 8,580,000 7,800,000 7,176,000 kW 10,508 7,219 5,848 4,980 4,432 4,021 3,701 3,427 3,290 3,061 2,741 2,513 2,284 2,102