ECR International MGB-50J Instruction manual

P/N 240011584, Rev. A [07/30/2016]
An ISO 9001-2008 Certified Company
Manufactured by:
ECR International, Inc.
2201 Dwyer Avenue, Utica NY 13501
web site: www.ecrinternational.com
MGB
CAST IRON GAS FIRED BOILERS
FOR FORCED HOT WATER
with Honeywell Control
INSTALL ATION, OPER ATION
& MAINTENANCE MANUAL
Models
MGB-50J
MGB-75J
MGB-100J
MGB-125J
MGB-150J
MGB-170J
MGB-200J
Tested For 100 psi.
ASME
Working Pressure
C.S.A. Certied
For Natural Gas
Or Propane

2
Table 1 - Dimensions
Boiler No. Natural Gas
Inlet*
Dimensions Pump size Supply &
Return Tappings
ABCD** EF
50 ½" 11⅛" 5½"4" 30¾" 36¼" 5¾" 1¼"
75 ½" 15" 7½"5" 30¾" 37¾" 5¾" 1¼"
100 ½" 15" 7½"6" 30¾" 37¼" 6" 1¼"
125 ½" 18⅞" 9½"6" 30¾" 37¼" 6" 1¼"
150 ½" 18⅞" 9½"7" 30¾" 37¾" 6¾" 1¼"
170 ½" 22¾"11½"7" 30¾" 38¾" 6¾" 1¼"
200 ½" 22¾"11½"8" 30¾" 38¾" 7¾" 1¼"
* Propane gas inlet, all units, 1/2"
** D is minimum height for low water cutoff installation
DIMENSIONS
P/N 240011584 Rev. A [07/30/2016]
Figure 1 - Dimensions
"E"
4½"
1¼" Return
"B"
"F"
14"
4¼"
4¼"
1¼" Supply
2½"
"A"
"D"**
3½"
27"
5½"
3"
"C"

3
Safety Symbols & Warnings
The following dened symbols are used throughout this
manual to notify the reader of potential hazards of varying
risk levels.
SAFETY SYMBOLS AND WARNINGS
NOTICE
Used to address practices not related to personal
injury.
CAUTION
Indicates a hazardous situation which, if not avoided,
could result in minor or moderate injury.
!
WARNING
Indicates a hazardous situation which, if not avoided,
could result in death or serious injury.
!
DANGER
Indicates a hazardous situation which, if not avoided,
WILL result in death or serious injury
!
IMPORTANT: Read the following instructions
COMPLETELY before installing!!
KEEP THIS MANUAL NEAR BOILER
RETAIN FOR FUTURE REFERENCE
WARNING
Keep boiler area clear and free from combustible
materials, gasoline and other ammable vapors
and liquids.
DO NOT obstruct air openings to the boiler room.
Modication, substitution or elimination of factory
equipped, supplied or specied components may
result in personal injury or loss of life.
TO THE OWNER - Installation and service of this
boiler must be performed by a qualied installer.
TO THE INSTALLER - Leave all instructions with
boiler for future reference.
When this product is installed in the
Commonwealth of Massachusetts the installation
must be performed by a Licensed Plumber or
Licensed Gas Fitter.
!
WARNING
Fire, explosion, asphyxiation and electrical shock
hazard. Improper installation could result in death
or serious injury. Read this manual and understand
all requirements before beginning installation.
!
Dimensions......................................................2
Safety Symbols and Warnings ............................3
Ratings & Data - Natural Gas & Propane Gas ........4
Installation Procedure .......................................5
Ventilation & Combustion Air.............................. 6
Connecting Supply and Return Piping ..................7
Connecting Supply and Return Piping ..................8
Vent Installation ............................................. 12
Vent System Modication................................. 12
Vent Damper Installation & Instructions............. 13
Connecting Gas Service................................... 14
Electrical Section ............................................ 15
Wiring Diagram ............................................. 16
Lighting Instructions ....................................... 18
Normal Sequence of Operation ......................... 19
General Instructions ....................................... 19
Checking Gas Input Rate To Boiler .................... 21
Appendix A - Control Module................. ........... 22
Appendix B-1 - Vent Damper Harness ............... 30
Appendix B-2 - Vent Damper Troubleshooting..... 31
CAUTION
Laceration, burn hazard. Metal edges and parts
may have sharp edges and/or hot. Use appropriate
personal protection equipment to include safety
glasses and gloves when installing or servicing this
boiler. Failure to follow these instructions could result
in minor or moderate injury.
!
P/N 240011584 Rev. A [07/30/2016]

4
Table 2 - Ratings and Capacities
Boiler
No.
(1)
Input
Mbh
(1)
Heating
Capacity Mbh
(2)
Net AHRI
Rating Water
Mbh
AFUE No.
of
Burners
(3)
Recommended
Air Cushion
Tank
Water
Content
(Gals.)
(1)
High
Altitude Input
Mbh
50J 50 42 37 83.5 115 2.4 45
75J 75 63 55 83.1 215 4.0 67.5
100J 100 83 72 83.0 230 4.0 90
125J 125 104 90 82.0 330 5.6 112.5
150J 150 124 108 83.0 330 5.6 135
170J 170 139 121 82.0 430 7.2 153
200J 200 165 143 82.0 430 7.2 180
RATINGS & DATA - NATURAL GAS & PROPANE GAS
P/N 240011584 Rev. A [07/30/2016]
EXPLANATORY NOTES
-- All boilers are design certied for installation on noncombustible oor.
-- For installation on combustible oors use combustible oor kit.
-- Recommended chimney height 20 feet. In special cases where conditions permit, chimney height may be
reduced to 10 feet. Refer to the latest revision of NFGC part 11.
-- Electric service to be 120 Volts, 15 Amps, 60 Hz.
-- The MEA number for the this boiler is 19-79-E.
(1) Input rating for sea level to 2,000 ft. (610m) above sea level.
United States, over 2000 ft (610m) above sea level. Reduce input rate 4% for every 1000 ft (304m) above sea
level.
Canada, 2000 ft (610m) to 4500 (1350m) above sea level reduce input per table. Over 4500 ft (1350m) above sea
level. Contact Provincial authority having jurisdiction.
(2) Net AHRI Water Ratings shown based on piping and pickup allowance of 1.15. Consult manufacturer before selecting
boiler for installations having unusual piping and pickup requirements, such as intermittent system operation,
extensive piping systems, etc.
For forced hot water systems where boiler and all piping within area to be heated, boiler may be selected on basis of
its heating capacity.
(3) Tank sized for non-ferrous baseboard or radiant panel systems. Increase size for cast iron baseboard and
radiation.
STANDARD EQUIPMENT: Boiler Jacket, Cast Iron Boiler Battery, High Limit Control, Intermittent Electric Ignition Pilot
System, Vent Damper Relay, Theraltimeter Gauge, Circulator With Return Piping To Boiler, Main Gas Burners, Gas Control
(Includes Automatic Gas Valve, Gas Pressure Regulator, Intermittent Pilot, Safety Shutoff, Pilot Flow Adjustment, Pilot Filter),
A.S.M.E. Relief Valve, Drain Valve, Spill Switch, Rollout Switch, Combination Gas Control, Automatic Vent Damper. Not Shown
Are: Wiring Harness, Thermocouple, Non-linting Safety Pilot.

5
1. Installation must conform to the requirements of the
authority having jurisdiction or, in the absence of such
requirements, to the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, and/or Natural Gas and Propane
Installation Code, CAN/CSA B149.1.
2. Where required by the authority having jurisdiction, the
installation must conform to the Standard for Controls
and Safety Devices for Automatically red Boilers,
ANSI/ASME CSD-1.
3. Boiler series is classied as a Category I. Vent
installation shall be in accordance with "Venting of
Equipment ," of the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, or "Venting Systems and Air Supply
for Appliances," of the Natural Gas and Propane
Installation Code, CAN/CSA B149.1, or applicable
provisions of the local building codes.
4. Boiler has met safe lighting and other performance
criteria with the gas manifold and control assembly on
the boiler per the latest revision of ANSI Z21.13/CGA
4.9.
5. Install boiler such that gas ignition system components
are protected from water (dripping, spraying, rain,
etc.) during appliance operation and service, (circulator
replacement, condensate trap, control replacement,
etc.).
6. Locate boiler on level, solid base as near chimney as
possible and centrally located with respect to heat
distribution system as practical.
7. Allow 24 inches (610mm ) at front and right side for
servicing and cleaning.
8. When installed in utility room, door should be wide
enough to allow largest boiler part to enter, or to
permit replacement of another appliance such as water
heater.
WARNING
Fire hazard. Do not install boiler on combustible
ooring or carpeting. Failure to follow these
instructions could result in death or serious injury.
!
9. FOR INSTALLATION ON NON-COMBUSTIBLE FLOORS
ONLY - For installation on combustible ooring special
base must be used. (See Repair Parts, Optional Kits
Manual). Do not install boiler on carpeting. Minimum
clearances to combustible construction are:
TOP ....................................18 IN. (457mm)
FRONT .........................................ALCOVE *
FLUE CONNECTOR ................. 6 IN. (152mm)
REAR ................................... 4 IN. (102mm)
CONTROL SIDE ..................... 9 IN. (229mm)
OTHER SIDE ........................... 3 IN. (76mm)
HOT WATER PIPING ................ Per Local Code
NOTE: Greater clearances for access should supersede fire
protection clearances.
* Denition of Alcove is three sided space with no wall in
front of boiler. ANSI standard for alcove is 18 inches from
front of appliance to leading edge of side walls as shown
below.
INSTALLATION PROCEDURE
WARNING
Improper installation, adjustment, alteration, service
or maintenance could result in death or serious
injury.
!
3"
4"
BOILER
18"
9"
Front
Minimum Clearances to Combustible Construction
(as seen from above)
P/N 240011584 Rev. A [07/30/2016]

6
VENTILATION & COMBUSTION AIR
Provide combustion air and ventilation air in accordance
with the section “Air for Combustion and Ventilation,” of the
National Fuel Gas Code, ANSI Z223.1/NFPA 54, or Sections
8.2, 8.3 or 8.4 of Natural Gas and Propane Installation
Code, CAN/CSA B149.1, or applicable provisions of local
building codes.
Provide make-up air where exhaust fans, clothes dryers,
and kitchen ventilation equipment interfere with proper
operation.
National Fuel Gas Code recognizes several methods
of obtaining adequate ventilation and combustion air.
Requirements of the authority having jurisdiction may
override these methods.
xEngineered Installations. Must be approved by
authority having jurisdictions.
xMechanical Air Supply. Provide minimum of 0.35
cfm per Mbh for all appliances located within space.
Additional requirements where exhaust fans installed.
Interlock each appliance to mechanical air supply
system to prevent main burner operation when
mechanical air supply system not operating.
xAll Indoor Air. Calculate minimum volume for all
appliances in space. Use a different method if
minimum volume not available.
оStandard Method. Cannot be used if known air
inltration rate is less than 0.40 air changes per
hour. See Table 3 for space with boiler only. Use
equation for multiple appliances.
Volume ≥ 50 ft3x Total Input [Mbh]
оKnown Air Inltration Rate. See Table 3 for
space with boiler only. Use equation for multiple
appliances. Do not use an air inltration rate
(ACH) greater than 0.60.
Volume ≥ 21 ft3/ACH x Total Input [Mbh]
оRefer to National Fuel Gas Code for opening
requirements between connection indoor spaces.
xAll Outdoor Air. Provide permanent opening(s)
communicating directly or by ducts with outdoors.
оTwo Permanent Opening Method. Provide opening
commencing within 12 inches of top and second
opening commencing within 12 inches of bottom
enclosure.
Direct communication with outdoors or
communicating through vertical ducts. Provide
minimum free area of 1 in2per 4 Mbh of total
input rating of all appliances in enclosure.
Communicating through horizontal ducts.
Provide minimum free area of 1 in2per 2
Mbh of total input rating of all appliances in
enclosure.
оOne Permanent Opening Method. Provide opening
commencing within 12 inches of top of enclosure.
Provide minimum clearance of 1 inch on sides
and back and 6 inches on front of boiler (does not
supersede clearance to combustible materials).
xRefer to National Fuel Gas Code for additional
requirements for louvers, grilles, screens and air
ducts.
xCombination Indoor and Outdoor Air. Refer to
National Fuel Gas Code for application information.
National Gas and Propane Installation Code Requires
providing air supply in accordance with:
xSection 8.2 and 8.3 when combination of appliances
has a total input of up to and including 400 Mbh (120
kW).
оDoes not have draft control device.
xSection 8.4 when combination of appliances has total
input exceeding 400 Mbh (120 kW).
xRefer to Natural Gas and Propane Installation Code
for specic air supply requirements for enclosure
or structure where boiler is installed, including air
supply openings and ducts.
Table 3 - Space With Boiler Only
Room Cubic Feet Volume
Input Mbh Standard
Method
Known Air Inltration Rate Method (ACH - Air Changes Per Hour)
0.1 0.2 0.3 0.4 0.5 0.6
50 2500 10500 5250 3500 2625 2100 1750
75 3750 15750 7875 5250 3938 3150 2625
100 5000 21000 10500 7000 5250 4200 3500
125 6250 26250 13125 8750 6563 5250 4375
150 7500 31500 15750 10500 7875 6300 5250
170 8500 35700 17850 11900 8925 7140 5950
200 10000 42000 21000 14000 10500 8400 7000
P/N 240011584 Rev. A [07/30/2016]

7
CONNECTING SUPPLY AND RETURN PIPING
Check local
codes for
maximum
distance
from oor
or allowable
safe point of
discharge.
RELIEF VALVE
DISCHARGE
LINE
WARNING
Burn or Scald Hazard. Discharge line shall be installed to relief valve outlet connection to avoid burns,
scalding, or water damage due to discharge of steam and/or hot water during operation.
Discharge line shall:
xconnect to relief valve outlet and piped down to safe point of disposal. Check local codes for maximum
distance from oor or allowable safe point of discharge.
xbe of pipe size equal to or greater than that of the relief valve outlet over the entire length of discharge
line;
xhave no intervening shutoff valve between safety relief valve and discharge to atmosphere (do not plug or
place any obstruction in discharge line.
xterminate freely to atmosphere where any discharge will be clearly visible and at no risk of freezing;
xallow complete drainage of the valve and the discharge line;
xbe independently supported and securely anchored to avoid applied stress on the relief valve;
xbe as short and straight as possible;
xterminate with plain end (not threaded);
xbe constructed of material suitable for exposure to temperatures of 375° F (191°C); or greater.
Refer to local codes and appropriate ASME Boiler and Pressure Vessel Code for additional installation
requirements.
!
Figure 2 - Safety Relief Valve
P/N 240011584 Rev. A [07/30/2016]

8
Circulators in following illustrations are mounted on system supply side, mounting on system return side is also
acceptable practice.
AIR
SEPARATOR
1. Boiler used in connection with refrigeration system,
install so chilled medium is piped in parallel with boiler
with appropriate valves to prevent chilled medium from
entering boiler. See Figure 3.
2. Boiler piping system of hot water boiler connected to
heating coils located in air handling units where they
may be exposed to refrigerated air circulation must be
equipped with ow control valves or other automatic
means to prevent gravity circulation of boiler water
during cooling cycle.
3. Hot water boilers installed above radiation level or
as required by authority having jurisdiction must be
provided with low water cut-off device.
4. Boiler connected to heating system utilizing multiple
zoned circulators, each circulator must be supplied with
ow control valve to prevent gravity circulation.
5. Hot water boilers and system must be lled with water
and maintained to minimum pressure of 12 psi.
6. For Low Water Cutoff, see Figure 1 for minimum height.
Use Kit #550002998 and follow instructions enclosed
with kit. For other LWCO's follow their manufacture
specic instructions.
7. Bypass piping is optional which gives ability to
adjust supply boiler water temperature to t system
or condition of installation. This method of piping,
however, is not typically required for baseboard heating
systems. Typical installations where bypass piping is
used are as follows:
A. This method is used to protect boilers from
condensation forming due to low temperature
return water. Generally noticed in large converted
gravity systems or other large water volume
systems. Figures 4 and 5.
B. These methods are used to protect systems using
radiant panels and material they are encased in
from high temperature supply water from boiler
and protect boiler from condensation.
NOTE#1: When using bypass piping, adjust
valves V1 & V2 until desired system temperature
is obtained. See Figure 5, page 9.
NOTE#2: Bypass loop must be same size piping
as supply and return piping.
CONNECTING SUPPLY AND RETURN PIPING
Figure 3 - Circulators Mounted on Supply System, Boiler Used In Conguration with Chiller System.
See Special Conditions, Page 9
P/N 240011584 Rev. A [07/30/2016]

9
BOILER
WATER INLET
ALTERNATE
CIRCULATOR
LOCATION
TO SYSTEM FROM SYSTEM
CIRCULATOR
SHUT-OFF
VALVE
PRESSURE
REDUCER VALVE
CHECK VALVE
BALL VALVE
3 WAY MIXING
VALVE
AIR SEPARATOR
HOSE BIB
EXPANSION
TANK
8. Installation using circulators and zone valves are
shown in Figures 6 through 9. For further piping
information refer to AHRI Installation and Piping
Guide.
WARNING
Burn and scald hazard. Safety relief valve could
discharge steam or hot water during operation.
Install discharge piping per these instructions.
!
9. Install discharge piping from safety relief valve. See
Warning, Page 7 and Figure 2.
CONNECTING SUPPLY AND RETURN PIPING
BOILER ALTERNATE
CIRCULATOR
LOCATION
TO SYSTEM FROM SYSTEM
V2V1
CIRCULATOR
SHUT-OFF
VALVE
PRESSURE
REDUCER VALVE
CHECK VALVE
BALL VALVE AIR SEPARATOR
ZONE VALVE
EXPANSION
TANK
WATER INLET
SYSTEM
CIRCULATOR
Figure 4 - Bypass Piping With Mixing Valve
Figure 5 - Bypass Piping - Fixed Low Temp Only With Zone Valve
P/N 240011584 Rev. A [07/30/2016]

10
CONNECTING SUPPLY AND RETURN PIPING
Figure 6 - Single Zone System With DHW
Figure 7 - Multi Zone System With Circulators And DHW
P/N 240011584 Rev. A [07/30/2016]

11
CONNECTING SUPPLY AND RETURN PIPING
Figure 8 - Multi Zone System With Zone Valves And DHW (With Circulator)
Figure 9 - Multi Zone System With Zone Valves And DHW (With Zone Valve)
P/N 240011584 Rev. A [07/30/2016]

12
When an existing boiler is removed from a common
venting system, the system is likely to be too large for the
proper venting of the appliances sill connected to it. If
this situation occurs, the following test procedure must be
followed:
1. Vent pipe must slope upward from the boiler not
less then ¼ inch for every 1 foot (21mm/m) to vent
terminal.
2. Horizontal portions of venting system shall be
supported rigidly every 5 feet and at the elbows. No
portion of vent pipe should have any dips or sags.
3. Boiler series is classied as a Category I. Vent
installation shall be in accordance with "Venting of
Equipment," of the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, or "Venting Systems and Air Supply
for Appliances," of the Natural Gas and Propane
Installation Code, CAN/CSA B149.1, or applicable
provisions of the local building codes.
4. Inspect chimney. Verify chimney is constructed
according to NFPA 211. Vent or vent connector shall
be Type B or metal pipe having resistance to heat and
corrosion not less than that of galvanized sheet steel or
aluminum not less than 0.016 inch thick (No. 28 Ga).
5. Connect ue pipe from draft hood to chimney. Bolt or
screw joints together to avoid sags. Flue pipe should
not extend beyond inside wall of chimney. Do not
install manual damper in ue pipe or reduce size of
ue outlet except as provided by the latest revision of
ANSI Z223.13 or CAN/CSA B149.1. Protect combustible
ceiling and walls near ue pipe with reproof insulation.
Where two or more appliances vent into a common
ue, the area of the common ue must be at least
equal to the area of the largest ue plus 50 percent of
the area of each additional ue.
VENT INSTALLATION
VENT SYSTEM MODIFICATION
REMOVAL OF BOILER FROM VENTING SYSTEM
At the time of removal of an existing boiler, the following
steps shall be followed with each appliance remaining
connected to the common venting system placed in
operation, while the other appliances remaining connected
to the common venting system are not in operation.
1. Seal an unused opening in the common venting
system.
2. Visually inspect the venting system for proper size and
horizontal pitch and determine there is no blockage or
restriction, leakage, corrosion and other deciencies
which could cause an unsafe condition.
3. Insofar as is practical, close all building doors and
windows and all doors between the space in which the
appliances remaining connected to the common venting
system are located and other spaces of the building.
Turn on clothes dryers and any other appliance not
connected to the common venting system. Turn on
any exhaust fans, such as range hoods and bathroom
exhausts, so they operate at maximum speed. Do
not operate a summer exhaust fan. Close replace
dampers.
4. Place in operation the appliance being inspected. Follow
the lighting instructions. Adjust thermostat so appliance
will operate continuously.
5. Test for spillage at the draft hood relief opening after
5 minutes of main burner operation. Use the ame of
a match or candle, or smoke from a cigarette, cigar or
pipe.
6. After it has been determined that each appliance
remaining connected to a common venting system
properly vents when tested as outlined above, return
doors, windows, exhaust fans, replace dampers and
any other gas burning appliances to their previous
condition of use.
7. Any improper operation of the common venting system
should be corrected so the installation conforms with
the National Fuel gas Code, ANSI Z223.1/NFPA 54,
and/or the Natural Gas and Propane Installation Code,
CAN/CSA B149.1. When re-sizing any portion of the
common venting system, the common venting system
should be re-sized to approach the minimum size
determined using the appropriate tables in Chapter 13
of the National Fuel Gas Code, ANSI Z223.1/NFPA 54,
and/or the Natural Gas and Propane Installation Code,
CAN/CSA B149.1.
WARNING
Boiler and venting installations shall be performed
by a qualied expert and in accordance with the
appropriate manual. Installing or venting boiler
or other gas appliance with improper methods or
materials may result in serious injury or death due
to re or to asphyxiation from poisonous gases such
as carbon monoxide with is odorless and invisible.
!
WARNING
Do not connect boiler to any portion of mechanical
draft system operating under positive pressure.
!
P/N 240011584 Rev. A [07/30/2016]

13
1. Verify only boiler is serviced by Vent Damper. Figure
11.
2. Clearance of not less than 6 inches (152mm) between
Vent Damper and combustible material must be
maintained. Additional clearance should be allowed for
service of Vent Damper.
3. Vent Damper must be in the open position when
appliance main burners are operating.
4. Vent Damper position indicator must be in visible
location following installation.
5. Thermostat's heat anticipator must be adjusted to
match total current draw of all controls associated with
boiler during heating cycle.
VENT DAMPER INSTALLATION & INSTRUCTIONS
Figure 10 - Damper Motor Wiring Figure 11 - Vent Damper Placement
DAMPER INSTALLATION
Follow Damper installation instructions provided with
damper. See Figure 10.
Damper Motor
Vent Outlet
Vent Damper
Damper Wire
Haness
Limit Control
REFER TO DAMPER MANUFACTURER'S
INSTALLATION INSTRUCTIONS FOR
POSITION OF DAMPER
CONTROL BOX
ACCEPTABLE VENT
DAMPER LOCATIONS
BOILER
HOT WATER HEATER
CHIMNEY
UN-ACCEPTABLE
DAMPER LOCATIONS
DAMPER INSTRUCTIONS
P/N 240011584 Rev. A [07/30/2016]

14
CONNECTING GAS SERVICE
General
xUse piping materials and joining methods acceptable
to authority having jurisdiction. In absence of such
requirements:
xUSA - National Fuel gas Code, ANSI Z223.1/NFPA 54
xCanada - Natural Gas and Propane Installation Code,
CAN/CSA B149.1
xSize and install gas piping system to provide sufcient
gas supply to meet maximum input at not less than
minimum supply pressure. See Table 4.
xSupport piping with hooks straps, bands, brackets,
hangers, or building structure components to prevent or
dampen excessive vibrations and prevent strain on gas
connection. Boiler will not support piping weight.
xUse thread (joint) compound (pipe dope) suitable for
liqueed petroleum gas.
xInstall eld sourced manual main shutoff valve, ground
joint union, and sediment trap upstream of gas valve.
See Figure 12.
Table 5 Natural Gas Propane
Min. Supply Pressure 5" w.c. 11" w.c.
Max. Supply Pressure 13.5" w.c. 13.5" w.c.
Manifold Pressure 3.5" w.c. 10.5" w.c.
DANGER
Fire Hazard. Do not use matches, candles, open
ames, or other methods providing ignition source.
Failure to comply will result in death or serious
injury.
!
Leak Check Gas Piping
Pressure test boiler and gas connection before placing
boiler in operation.
x Pressure test over 1/2 psig (3.5 kPa). Disconnect
boiler and its individual gas shutoff valve from gas
supply system.
x Pressure test at 1/2 psig (3.5 kPa) or less. Isolate
boiler from gas supply system by closing manual gas
shutoff valve.
x Locate leakage using gas detector, non-corrosive
detection uid, or other leak detection method
acceptable to authority having jurisdiction. Do not
use matches, candles, open ames, or other methods
providing ignition source.
x Correct leaks immediately and retest.
MAXIMUM CAPACITY OF PIPE IN CUBIC FEET OF
GAS/HOUR
(Gas Pressure = 0.5 psig or less, Pressure Drop = 5
in. w/c)
Table 4
Length of
Pipe (Feet)
Nominal Iron Pipe Size
½” ¾” 1” 1¼”
10 175 360 680 1400
20 120 250 465 950
30 97 200 375 770
40 82 170 320 660
60 66 138 260 530
80 57 118 220 460
100 50 103 195 400
For additional information refer to the National Fuel Gas
Code Handbook.
Figure 12 - Gas Piping
CAUTION
WHAT TO DO IF YOU SMELL GAS
xDo not try to light any appliance.
xDo not touch any electrical switch; do not use
any phone in your building.
xImmediately call your gas supplier from a
neighbor’s phone. Follow gas supplier’s
instructions.
xIf you cannot reach your gas supplier, call the re
department.
!
P/N 240011584 Rev. A [07/30/2016]

15
ELECTRICAL SECTION
ELECTRICAL WIRING
See wiring diagrams on the following two pages for
details.
Electrically bond boiler to ground in accordance with
requirements of authority having jurisdiction. Refer to:
xUSA- National Electrical Code, ANSI/NFPA 70.
xCanada - Canadian Electrical Code, Part I, CSA C22.1:
Safety Standard for Electrical Installations.
If using LWCO kit 550002998 wiring instructions and wiring
diagram are included with the kit.
THERMOSTAT INSTALLATION
1. Thermostat should be installed on inside wall about
four feet above oor.
2. NEVER install thermostat on outside wall.
3. Do not install thermostat where it will be affected by
drafts, hot or cold pipes, sunlight, lighting xtures,
televisions, replace, or chimney.
4. Check thermostat operation by raising and lowering
thermostat setting as required to start and stop
burners.
5. Instructions for nal adjustment of thermostat
are packaged with thermostat (adjusting heating
anticipator, calibration, etc.)
WARNING
Electrical shock hazard. Turn OFF electrical power
supply at service panel before making electrical
connections. Failure to do so could result in death
or serious injury.
!
P/N 240011584 Rev. A [07/30/2016]

16
WIRING DIAGRAM
Figure 13 - Integrated High Limit Electronic Ignition Control
I
WARNING
Modication, substitution or elimination of factory
equipped, supplied or specied components may
result in personal injury or loss of life.
!
P/N 240011584 Rev. A [07/30/2016]

17
WIRING DIAGRAM
Figure 14 - Integrated High Limit Electronic Ignition Control
P/N 240011584 Rev. A [07/30/2016]

18
LIGHTING INSTRUCTIONS
LIGHTING PROCEDURE FOR BOILER WITH
INTERMITTENT PILOT SYSTEM
A. This appliance is equipped with an ignition device which
automatically lights the pilot. Do not try to light the
appliance by hand.
CAUTION
WHAT TO DO IF YOU SMELL GAS
xDo not try to light any appliance.
xDo not touch any electrical switches; do not use
any phone in your building.
xImmediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
xIf you cannot reach your gas supplier, call the re
department.
!
OPERATING INSTRUCTIONS FOR INTERMITTENT
PILOT SYSTEM
1. STOP! Read the safety information to the left.
2. Set the thermostat to lowest setting.
3. Turn off all electric power to the appliance.
4. This appliance is equipped with an ignition device which
automatically lights the pilot. Do not try to light the
pilot by hand.
Figure 15 - Intermittent Pilot
5. Turn gas control knob clockwise to “OFF.”
6. Wait (5) minutes to clear out any gas. If you then smell
gas, STOP! Follow “What To Do If You Smell Gas” in the
safety information to the left. If you don’t smell gas, go
on to the next step.
7. Turn gas control knob counterclockwise to “ON.”
8. Turn on all electric power to the appliance.
9. Set thermostat to desired setting.
10. If the appliance will not operate, follow the instructions
“ To Turn Off Gas To Appliance ” , and call qualied
service technician or your gas supplier.
TO TURN OFF GAS TO THE APPLIANCE
1. Set the thermostat to lowest setting.
2. Turn off all electric power to the appliance if service is
to be performed.
3. Push in gas control knob slightly and turn clockwise
to "OFF." DO NOT FORCE.
4. Call qualied service technician.
WARNING
If you do not follow these instructions
exactly, a re or explosion may result
causing property damage, personal injury
or loss of life.
xThis appliance is equipped with an ignition device
which automatically lights burner. Do NOT try to
light this burner by hand.
xBefore operating smell all around appliance area
for gas. Be sure to smell next to oor because
some gas is heavier than air and will settle to the
oor.
xUse only your hand to turn the gas shutoff
valve. Never use tools. If valve will not turn
by hand, do not try to repair it, call a qualied
service technician. Force or attempted repair may
result in re or explosion.
xDo not use this appliance if any part has
been under water. Immediately call a qualied
service technician to inspect appliance and to
replace any part of control system and any gas
control which has been under water.
!
NOTICE
Before lighting any type of pilot burner (standing or
intermittent), verify the hot water boiler and system
are full of water to minimum pressure of 12 psi in
the system, also verify system is vented of air. Set
operating control of thermostat to “below” normal
setting. Refer to following appropriate lighting
instruction.
P/N 240011584 Rev. A [07/30/2016]

19
NORMAL SEQUENCE OF OPERATION
GENERAL INSTRUCTIONS
Thermostat actuates on call for heat,
completing circuit to control. Completed
circuit to control will rst activate circulator
and damper which will close end switch inside
damper. Completes circuit to ignition system,
ignition takes place.
In event boiler water temperature exceeds
high limit setting on boiler mounted high limit
control, power is interrupted between control
system and ignition system. Power remains
off until boiler water temperature drops below
high limit setting. Circulator continues to
operate under this condition until thermostat is
satised.
In event ow of combustion products through
boiler venting system becomes blocked, blocked
vent safety switch shuts main burner gas off.
Similarly, if boiler ue-way becomes blocked,
ame rollout safety switch shuts main burner
gas off. Figure 16 .If either of these conditions
occur, DO NOT ATTEMPT TO PLACE BOILER
BACK INTO OPERATION. CONTACT
CERTIFIED SERVICE AGENCY.
Blocked Vent
Safety Switch
Rollout Switch
4 Section Boiler
Rollout Switch
2,3,5
Section Boiler
Intergral Draft
Hood
Base
Burner
Door
*Burners
Orices
Jacket Base
Panel
Before seasonal start-up, have a certied service agency
check boiler for soot and scale in ues, clean burners and
check gas input rate to maintain high operating efciency.
WARNING
Label all wires prior to disconnection when servicing
controls. Wiring errors could cause improper and
dangerous operation.
!
Verify proper operation after servicing
Service agency will verify system is lled with water to
minimum pressure and open air vents, if used, to expel any
air accumulated in the system. Check entire piping system
and, if any leaks appear, have them repaired.
Circulators need to be checked and maintained.
Refer to circulator manufacturer's instructions.
Inspect venting system at the start of each heating
season. Check vent pipe from boiler to chimney for signs of
deterioration by rust or sagging joints. Repair if necessary.
Remove vent pipe at base of chimney or ue and using a
mirror, check vent for obstruction and verify vent is in good
working order.
Boiler ue gas passageways may be inspected by a light
and mirror. Remove burner door. Figure 16 . Place trouble
lamp in ue collector through draft relief opening. With
mirror positioned above burners, ue gas passageways can
be checked for soot or scale.
This procedure should be followed to clean ue gas
passageways:
1. Remove burners from combustion chamber by raising
burners up from manifold orices and pulling toward
front of boiler. Figure 16 .
2. Disconnect vent pipe from draft hood.
3. Remove top jacket panel.
4. Remove combination ue collector and draft hood from
boiler castings by loosening nuts on hold down bolts
located on each side of collector. Figure 16 .
5. Place sheet of heavy paper or similar material over
bottom of base and brush down ue passageways. Soot
and scale will collect on paper and is easily removed
with the paper.
6. With paper still in place in base, clean top of boiler
castings of boiler putty or silicone used to seal between
castings and ue collector. Verify chips are not lodged
in ue passageways.
When cleaning process is complete, restore boiler
components to their original position. Use IS-808 GE
silicone (available from distributor) to seal around ue
collector and boiler castings.
Figure 16 - Blocked Vent Safety Switch, Roll-out
Safety Switch
* Burner shipping retention clips (not shown) may be removed if desired.
P/N 240011584 Rev. A [07/30/2016]

20
GENERAL INSTRUCTIONS
Figure 17 - Gas Burner Flame
Figure 19 - Gas Burner Pilot
Figure 18 - Combustion Chamber
BURNERS
ORIFICES
GAS VALVE
xMake visual inspection of main burner and pilot ames
at start of heating season and again in mid-season. Main
burner ame should have well dened inner blue mantel
with lighter blue outer mantel. Check burner throats and
burner orices for lint or dust obstruction. Figures 17
and 18.
xPilot ame should envelop ⅜ to ½ inch of tip of ignition/
sensing electrode. See Figure 19.
xTo adjust pilot ame, remove pilot adjustment cover
screw and turn inner adjustment screw counterclockwise
to increase or clockwise to decrease pilot
ame. Be sure to replace cover screw after adjustment to
prevent possible gas leakage. See Figure 15, Page 18.
xCheck burners and pilot for signs of corrosion, rust or
scale buildup.
xArea around boiler must be kept clear and free of
combustible materials, gasoline and other ammable
vapors and liquids.
xFree ow of combustion and ventilating air to boiler and
boiler room must not be restricted or blocked.
xInspect eld sourced low water cutoffs annually, or
as recommended by low water cutoff manufacturer.
Flush oat type low water cutoffs per manufacturer's
instructions.
xEmploy a qualied service agency to make annual
inspection of boiler and heating system. They are
experienced in making the inspections outlined above,
and, in event repairs or corrections are necessary,
trained technicians make the proper changes for safe
operation of the boiler.
P/N 240011584 Rev. A [07/30/2016]