U.S. Boiler Company B series 2 Service manual

103385-01 - 1/11 Price - $5.00
INSTALLATION, OPERATING AND
SERVICE INSTRUCTIONS FOR
Series 2®(model B)
Gas - Fired Boiler
9700609
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NOTE: The equipment shall be installed in accordance with those installation regulations in force in the area where the
installation is to be made. These shall be carefully followed in all cases. Authorities having jurisdiction shall be consulted before
installations are made.
All wiring on boilers installed in the USA shall be made in accordance with the National Electrical Code and/or local regulations.
All wiring on boilers installed in Canada shall be made in accordance with the Canadian Electrical Code and/or local regulations.
The New York City Department of Buildings has approved the Series 2B boiler: Approval No. MEA 96-96-E
The City of New York requires a Licensed Master Plumber supervise the installation of this product.
The Massachusetts Board of Plumbers and Gas Fitters has approved the Series 2B boiler. See the Massachusetts Board of
Plumbers and Gas Fitters website, http://license.reg.state.ma.us/pubLic/pb_pre_form.asp for the latest Approval Code or ask
your local Sales Representative.
The Commonwealth of Massachusetts requires this product to be installed by a Licensed Plumber or Gas Fitter.
The following dened terms are used throughout this manual to bring attention to the presence of hazards of various risk levels, or
to important information concerning the life of the product.
Table of Contents
I. Installation Instructions................... 4
II. Operating Instructions.....................18
III. Trouble Shooting..............................25
IV. Service..............................................26
V. Repair Part .......................................29
VI. Appendix
Low Water Cut Off...........................51
WARNING
FAILURE TO FOLLOW ALL INSTRUCTIONS IN PROPER ORDER CAN CAUSE PERSONAL INJURY OR
DEATH. READ ALL INSTRUCTIONS BEFORE INSTALLING.
DANGER
Indicates presence of a hazard which will cause
severe personal injury, death or substantial
property damage if ignored.
CAUTION
Indicates presence of a hazard which will or can
cause minor personal injury or property damage
if ignored.
WARNING
Indicates presence of a hazard which can cause
severe personal injury, death or substantial
property damage if ignored.
NOTICE
Indicates special instructions on installation,
operation, or maintenance which are important
but not related to personal injury hazards.
WARNING
SERVICE ON THIS BOILER SHOULD BE UNDERTAKEN ONLY BY TRAINED AND SKILLED PERSONNEL.
KEEP BOILER AREA CLEAR AND FREE FROM COMBUSTIBLE MATERIALS, GASOLINE AND OTHER
FLAMMABLE VAPORS AND LIQUIDS.
DO NOT PLACE ANY OBSTRUCTION IN THE BOILER ROOM THAT WILL HINDER THE FLOW OF
COMBUSTION AND VENTILATING AIR.

3
WARNING
READ THESE INSTRUCTIONS CAREFULLY BEFORE PROCEEDING WITH THE INSTALLATION OF BOILER.
POST INSTRUCTIONS NEAR BOILER FOR REFERENCE BY OWNER AND SERVICE TECHNICIAN. MAINTAIN
INSTRUCTIONS IN LEGIBLE CONDITION.
Boiler
Model
Number
Dimensions [Inches] Gas
Connection
For Automatic
Gas Valve
Water
Content
[gallons]
Recommended
Vent Size
[1] [2]
Approx.
Shipping
Weight
[lb.]
A B C D E F G
202 18-3/4 10-3/4 6-3/8 4 45-5/8 8-1/2 10 [3] 1/2 2.5 3" dia. x 15 ft. 212
202X 20 12 6 4 45-5/8 8-1/2 4-3/4 1/2 3.2 4" dia. x 15 ft. 262
203 20 12 6 4 45-5/8 8-1/2 4-3/4 1/2 3.2 4" dia. x 15 ft. 262
204 23-1/4 15-1/4 7-5/8 5 47-1/8 9-1/8 4-3/4 1/2 4 5" dia. x 15 ft. 306
205 26-1/2 18-1/2 9-1/4 6 48-1/2 9-3/4 5-1/4 1/2 4.7 6" dia. x 15 ft. 354
206 29-3/4 21-3/4 10-7/8 6 48-1/2 9-3/4 5-1/4 1/2 5.5 6" dia. x 15 ft. 414
207 33 25 12-1/2 7 50-1/8 10-3/8 6-5/8 3/4 6.2 7" dia. x 15 ft. 458
208 36-1/4 28-1/4 14-1/8 7 50-1/8 10-3/8 6-5/8 3/4 7 7" dia. x 15 ft. 514
209 39-1/2 31-1/2 15-3/4 8 52 11 7-1/4 3/4 7.7 8" dia. x 15 ft. 550
210 42-3/4 34-3/4 17-3/8 8 52 11 7-1/4 3/4 8.5 8" dia. x 15 ft. 608
[1] 15' chimney height is from bottom of draft hood opening to top of chimney.
[2] Refer to the National Fuel Gas Code for equivalent areas of circular and rectangular flue linings.
Maximum Allowable Working Pressure - 30 PSI (Water Only)
[3] 202 only. Dimension 'G' includes allowance for 4" x 3" reducer furnished with boiler. See Figure 8.
Figure 1

4
I . Installation Instructions
1. INSPECT SHIPMENT carefully for any signs of
damage. All equipment is carefully manufactured,
inspected and packed. Our responsibility ceases upon
delivery of Boiler to the carrier in good condition. Any
claims for damage or shortage in shipment must be led
immediately against the carrier by the consignee. No
claims for variances or shortages will be allowed by
Boiler Manufacturer unless presented within sixty (60)
days after receipt of equipment.
2.BOILER INSTALLATION must conform to the
requirements of the authority having jurisdiction, or in
the absence of such requirements, to:
U.S.A. - National Fuel Gas Code, ANSI Z223.1.
When required by the authority having juris-
diction, the installation must conform to
ANSI/ASME No. CSD-1.
CANADA - Installation Codes for Natural and LP Gas
Burning Appliances and Equipment, CAN/
CSA-B149.1.
3. These Gas Boilers are DESIGN CERTIFIED FOR
INSTALLATION ON COMBUSTIBLE FLOORING.
DO NOT INSTALL THESE BOILERS ON
CARPETING.
NOTICE
Do not drop boiler. Do not bump boiler jacket
against oor.
4. LOCATE BOILER in front of or behind installation
position before removing Crate. Locate on a level oor
as close to chimney as possible. For basement
installations, provide a solid base such as concrete, if
oor is not level or if water may be encountered on
oor around Boiler.
The boiler shall be installed such that the gas ignition
system components are protected from water (dripping,
spraying, rain, etc.) during boiler operation and service
(circulator replacement, control replacement, etc.).
DANGER
Do not install boiler where gasoline or other
ammable vapors or liquids, or sources of
hydrocarbons (i.e. bleaches, cleaners, chemicals,
sprays, paint removers, fabric softeners, etc.) are
used or stored.
5. REMOVE CRATE -
A. Remove all crate fasteners. Lift off outside
container.
B. Remove all screws and brackets securing boiler to
skid.
C. Save two of the wooden slats from the container
sleeve for use in Steps D & E.
D. Tilt the boiler to one side and slide a wooden slat
under the two raised feet.
E. Tilt the boiler to the other side and slide another
wooden slat under the two raised feet.
F. Slide the boiler forward or backward off the skid
using the two wooden slats as runners.
6. Move boiler to permanent position.
7. PROVIDE CLEARANCE and AIR for COMBUS-
TION and VENTILATION.
WARNING
Adequate combustion and ventilation air must be
provided to assure proper combustion.
A. CLEARANCES
1. ALL INSTALLATIONS - Practical service
clearances must be considered (see Figure 1). A
minimum of 24" (6.0cm) from the left side and
front jacket panels is recommended for servicing
but may be reduced to minimum shown in
Figure 2. Subject to boiler and system piping,
left side clearance may be reduced to 1" (2.5cm)
if right side clearance is increased to 9"
(22.9cm).
2. ALCOVE INSTALLATIONS - An alcove is
considered a closet as shown in Figure 2 less
front. Height clearance may be reduced to 27"
(68.6cm).
3. UNCONFINED SPACE (see denition,
paragraph (B) below) - Height clearance may be
reduced to 27" (68.6cm).
B. PROVIDE COMBUSTION AND VENTILATION
AIR in accordance with applicable provisions of
local building codes, or: U.S.A. - National Fuel
Gas Code, NFPA 54/ANSI Z223.1, Canada -
Natural and Propane Gas Installation Code, CAN/
CSA-B149.1.
1. CLOSET INSTALLATIONS (conned space) in
a building of other than unusually tight
construction (see denition below), provide
combustion and ventilation air as shown in
Figure 2.
2. Installations other than closet in paragraph (1) :
a. Determine volume of space (boiler room).
Rooms communicating directly with space
(through openings not furnished with doors)
are considered part of space.

5
e. For boiler located in a building of other than
unusually tight construction, adequate
combustion and ventilation air is normally
provided by fresh air inltration through
cracks around windows and doors.
f. For boiler located in building of unusually
tight construction, provide outdoor air
through two permanent openings which
communicate directly or by duct with the
outdoors or spaces (crawl or attic) freely
communicating with the outdoors. Locate
one opening within 12 inches (30.5cm) of
top of space. Locate remaining opening
within 12 inches (30.5cm) of bottom of
space. Minimum dimension of air opening is
3 inches (7.6cm). Size each opening per
following:
i. Direct communication with outdoors.
Minimum free area of 1 square inch
(6.5cm2) per 4,000 Btu per hour input of
all equipment in space.
ii. Vertical ducts. Minimum free area of 1
square inch (6.5cm2) per 4,000 Btu per
hour input of all equipment in space. Duct
cross-sectional area shall be same as
opening free area.
iii. Horizontal ducts. Minimum free area of 1
square inch (6.5cm2) per 2,000 Btu per
hour input of all equipment in space. Duct
cross-sectional area shall be same as
opening free area.
g. Ventilation Duct Louvers and Grilles. Equip
outside openings with louvers to prevent
entrance of rain and snow, and screens to
prevent entrance of insects and rodents.
Louvers and grilles must be xed in open
position or interlocked with equipment to
open automatically before burner operation.
Screens must not be smaller than ¼ inch
mesh.
Consider the blocking effect of louvers,
grilles and screens when calculating the
opening size to provide the required free
area. If free area of louver or grille is not
known, assume wood louvers have 20-25
percent free area and metal louvers and
grilles have 60-75 percent free area.
8. CONNECT GAS SERVICE from Meter to gas control
assembly in accordance with Local Piping Codes and
requirements of Gas Company, see Figure 1. They may
require piping of larger size than Control Assembly
Connection, especially if run from meter is long or
includes several elbows. (See Figure 1 for size of Gas
Connection to gas control assembly).
Volume [ft³](m3) = Length [ft](m) x Width
[ft](m) x Height [ft](m)
b. Determine Total Input of all appliances in
space. Round result to nearest 1,000 Btu per
hour (Btuh).
c. Determine type of space. Divide Volume by
Total Input.
i. If result is greater than or equal to 50 ft³
(1.4m3) per 1,000 Btuh, space is
considered an unconned space.
ii. If result is less than 50 ft³ (1.4m3) per
1,000 Btuh, space is considered a conned
space.
d.Determine building type. A building of
unusually tight construction has the
following characteristics:
i. Walls and ceiling exposed to outside
atmosphere have a continuous water vapor
retarder with a rating of 1 perm or less
with openings gasketed and sealed, and
ii. Weather-stripping has been added on
openable windows and doors, and
iii. Caulking or sealants applied in joints
around window and door frames, between
sole plates and oors, between wall-
ceiling joints, between wall panels, at
plumbing and electrical penetrations, and
at other openings.
Figure 2: Minimum Clearances

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A. Allowable loss of pressure to assure a burner
manifold pressure of 3½" (8.9cm) water for natural
gas.
B. Supply of gas to be provided in cubic feet.
C. Length of piping and number of ttings.
D. Specic gravity of gas.
E. Correction factor for specic gravity.
9. BOILER PIPING
CAUTION
Failure to properly pipe boiler may result in
improper operation and damage to boiler or
building.
A. CLEARANCES - Hot water pipes do not require
clearance from combustible construction.
B. Install drain valve and safety relief valve as shown
in Figures 1 and 3. Note - Safety relief valve must
be in vertical position.
C. Pipe safety relief valve discharge to oor.
Table 1: Maximum Capacity of Schedule 40 Pipe in CFH For Natural Gas Pressures of ½ psig or Less
Table 2: Equivalent Length of Fittings Table 3: Specic Gravity Correction Factors for
Natural Gas
This piping is to be supplied by the installer and must
include a trap, a ground joint union and a manual
shutoff valve upstream of the gas control assembly
outside of the jacket when codes require, see Figure 1.
A pipe thread compound resistant to the action of
liqueed petroleum gases should be applied to all
threaded joints in the gas piping. Pressure testing of the
Gas Supply Piping Boiler and its connections is
required before placing the boiler in operation.
The boiler and shutoff valve must be disconnected from
the gas supply piping system during any pressure
testing at pressures greater than ½ psig (3.5kPa).
The boiler must be isolated from the gas supply piping
system by closing its individual manual shutoff valve
during any pressure testing of the gas supply piping
system at pressures equal to or less than ½ psig
(3.5kPa).
RECOMMENDED SIZING OF GAS SUPPLY
PIPING TO BOILER FOR NATURAL GAS - shall
be such as to provide the required supply of gas without
undue loss of pressure between meter and the boiler.
Gas supply piping should be sized in accordance with
the Tables 1, 2 and 3. The following shall be taken into
account:
Length
[Feet]
0.3 Inch w.c. Pressure Drop 0.5 Inch w.c. Pressure Drop
½ ¾ 1 1¼ ½ ¾ 1 1¼
10 132 278 520 1,050 175 360 680 1,400
20 92 190 350 730 120 250 465 950
30 73 152 285 590 97 200 375 770
40 63 130 245 500 82 170 320 660
50 56 115 215 440 73 151 285 580
60 50 105 195 400 66 138 260 530
70 46 96 180 370 61 125 240 490
80 43 90 170 350 57 118 220 460
90 40 84 160 320 53 110 205 430
100 38 79 150 305 50 103 195 400
Fitting
Nominal Pipe Size
½ ¾ 1 1¼
45° Ell 0.7 1 1.2 1.6
90° Ell 1.6 2.1 2.6 3.5
Tee (As Elbow) 3.1 4.1 5.2 6.9
Specific
Gravity
Correction
Factor
Specific
Gravity
Correction
Factor
0.50 1.10 1.30 1.07
0.55 1.04 1.40 1.04
0.60 1.00 1.50 1.00
0.65 0.96 1.60 0.97
0.70 0.93 1.70 0.94
0.75 0.90 --- ---
0.80 0.87 --- ---

7
Figure 3: Recommended Water Piping for
Zone Valve Zoned Heating Systems
Figure 4: Recommended Piping
for Combination Heating & Cooling
(Refrigeration) Systems
WARNING
Safety relief valve discharge piping must be
piped near oor to eliminate potential of severe
burns. Do not pipe in any area where freezing
could occur. Do not install any shut-off valves.
D. Install circulator with anges, gaskets and bolts
provided. Five foot long circulator harness allows
circulator to be mounted on supply or return.
Connect harness to circulator and secure any excess
conduit.
E. For heating only system piping, see Figure 3.
Consult also I=B=R Installation Guides.
F. For space heating and domestic water heating with
Alliance SL™ water heater (intermittent circulation
only); install Alliance SL™ water heater as a
separate heating zone. Refer to Alliance SL™
Installation, Operating and Service Instructions for
additional information.
G. If this boiler is used in connection with refrigeration
systems, the boiler must be installed so that the
chilled medium is piped in parallel with the heating
boiler using appropriate valves to prevent the chilled
medium from entering the boiler, see Figure 4. Also
consult I=B=R Installation and Piping Guides.
If this Boiler is connected to heating coils located in
air handling units where they may be exposed to
refrigerated air, the boiler piping must be equipped
with ow control valves to prevent gravity
circulation of boiler water during the
operation of the cooling system.
H. Use a boiler bypass if the boiler is to be
operated in a system which has a large
volume or excessive radiation where low
boiler water temperatures may be
encountered (i.e. converted gravity
circulation system, etc.).
Install a pipe tee at the boiler return along
with a second tee in the supply piping as
shown in Figure 3. The bypass should be the same
size as the supply and return lines with valves
located in the bypass and supply outlet as illustrated
in Figure 3 in order to regulate water ow to
maintain higher boiler water temperatures.
Set the boiler supply valve to fully open position,
and the boiler bypass valve to half throttle. Operate
the boiler and adjust the bypass valve to achieve
180°F to 200°F supply water temperature by closing
the bypass valve to decrease supply temperature or
opening the bypass valve to increase water
temperature. If the bypass valve is fully opened and
the boiler water temperature is still below 180°F,
slowly begin closing the boiler supply valve to
achieve 180°F to 200°F supply water temperature.
Caution: Never fully close the boiler supply valve.
I. A hot water boiler installed above radiation level
must be provided with a low water cutoff device as
part of the installation.
If a low water cut-off is required, it must be
mounted in the system piping above the boiler.
The minimum safe water level of a hot water boiler
is just above the highest water containing cavity of
the boiler; that is, a hot water boiler must be full of
water to operate safely.
Refer to Section VI for low water cut-off piping and
wiring instructions.
J. If it is required to perform a long term pressure test
of the hydronic system, the boiler should rst be
isolated to avoid a pressure loss due to the escape of
air trapped in the boiler.

8
Figure 6
B. Pinch the black strain relief bushing installed in the
jacket right side panel to dislodge it from the jacket
and pull just enough of the black power cord out so
the blocked vent switch will reach the near side of
the draft hood skirt. Do not pull out more power
cord than necessary.
C. Position the mounting bracket (with switch attached)
onto the lower edge of the draft hood skirt by
locating the center tooth (with the #10 sheet metal
screw) on the outside and the other two teeth inside
the draft hood skirt. See Figure 6.
D. Slide the mounting bracket up tight against the
lower edge of the draft hood skirt, so that the #10
sheet metal screw is above the skirt's stiffening rib.
E. Secure the bracket in this position by tightening the
#10 sheet metal screw against the outer surface of
the draft hood skirt.
F. Reinsert the excess power cord through the jacket
side panel hole to take the slack out of the power
cord running up to the blocked vent switch.
G. Reposition the strain relief bushing around the
power cord at the jacket side panel, pinch the two
halves of the bushing together, and snap it back into
the hole in the jacket side panel to secure the power
cord to the jacket.
H. Be sure the power cord, mounting bracket, and
switch are secure and located as shown in Figure 6.
To perform a long term pressure test including the
boiler, ALL trapped air must rst be removed from
the boiler.
A loss of pressure during such a test, with no visible
water leakage, is an indication that the boiler
contained trapped air.
K. OXYGEN CORROSION:
Oxygen contamination of the boiler water will cause
corrosion of the iron and steel boiler components,
which can lead to failure. As such, any system must
be designed to prevent oxygen absorption in the rst
place or prevent it from reaching the boiler.
Problems caused by oxygen contamination of boiler
water are not covered by U.S. Boiler Company's
standard warranty.
There are many possible causes of oxygen
contamination such as:
1. Addition of excessive make-up water as a result
of system leaks.
2. Absorption through open tanks and ttings.
3. Oxygen permeable materials in the distribution
system.
In order to insure long product life, oxygen
sources should be eliminated. This can be
accomplished by taking the following measures:
1. Repairing system leaks to eliminate the need for
addition of make-up water.
2. Eliminating open tanks from the system.
3. Eliminating and/or repairing ttings which allow
oxygen absorption.
4. Use of non-permeable materials in the
distribution system.
5. Isolating the boiler from the system water by
installing a heat exchanger.
10. INSTALL DRAFT HOOD without modication on
outlet of ue collector (See Figure 1). Secure with sheet
metal screws.
WARNING
Do not alter boiler draft hood or place any
obstruction or non-approved damper in the
breeching or vent system. Flue gas spillage can
occur. ETL certication will become void.
11. INSTALL BLOCKED VENT SWITCH
The blocked vent switch assembly shipped taped to the
top of the boiler includes a power cord and a switch
attached to a mounting bracket. The mounting bracket
has a three tooth staggered comb stamping at one end
with a #10 sheet metal screw in the center tooth.
A. Untape the blocked vent switch assembly from the
top of the boiler and uncoil the power cord.

9
WARNING
Failure to properly install and use this Blocked
Vent Switch may result in property damage,
personal injury or loss of life.
12.TO MEET FEDERALLY MANDATED
EFFICIENCIES, THIS BOILER MUST BE
EQUIPPED WITH A VENT DAMPER.
OPEN THE VENT DAMPER CARTON and remove
the Installation Instructions. READ THE INSTALLA-
TION INSTRUCTIONS THOROUGHLY before
proceeding.
The automatic gas control valve supplied on each
Series 2®boiler provides the redundancy referenced in
the vent damper Installation Instructions.
CAUTION
Do not use one vent damper to control two heating
appliances.
A. The vent damper should be the same size as the
outlet of the Draft Hood. (See Figure 1) Unpack the
damper carefully - DO NOT FORCE IT CLOSED!
Forcing the damper may damage the gear train and
void the warranty. The damper assembly includes a
prewired connection harness for use on all 24V
Standing Pilot or electronic ignition control systems.
B. Mount the vent damper assembly after the draft
hood, as close to the draft hood as practicable
without modication to the draft hood or vent
damper. (Refer to Figure 7 and to instructions
packed with the vent damper for specic
instructions). This is a must for the wiring harness to
t and the damper position indicator to be visible to
the users.
Figure 7: Plug-in Damper Installation
NOTICE
Provide adequate clearance for servicing.
WARNING
Provide 6" (15.2cm) minimum clearance between
damper and combustible construction.
C. Install the 90° BX connector attached to the exible
conduit in the 7/8" knockout on the left side of the
jacket. Plug the factory wired Vent Damper Harness
into the polarized receptacle. Install a cable clamp
around the exible conduit and attach to the Jacket
top panel. (See Figure 7).
NOTICE
Please refer to the specications, installation
instructions and troubleshooting guide packed
in the vent damper carton for complete detailed
installation instructions. Also refer to Figure 7 in
this manual.
D Continuous Ignition (Standing Pilot) Only. Remove
knockout from vent damper blade.
E. Size 202 Only. Install 4" x 3" reducing tting on
vent damper outlet.
13. INSTALL VENT CONNECTOR from reducing
tting (202 Only), draft hood or damper to chimney, see
Figure 8.

10
DANGER
Inspect existing chimney before installing boiler.
Failure to clean or replace perforated pipe or tile
lining will cause severe injury or death.
A. Vent installation shall be in accordance with local
building codes; or the local authority having
jurisdiction; or the National Fuel Gas Code, ANSI
Z223.1/NFPA 54; or the Standard for Chimneys,
Fireplaces, Vents, and Solid Fuel Burning
Appliances, ANSI/NFPA 211. Both of the
aforementioned standards, ANSI Z223.1 and ANSI/
NFPA 211, specify Type B and Type L double wall
metal vents and re clay tile lined masonry
chimneys as suitable chimney constructions for
Category I, draft hood equipped appliances, such as
this Series 2®boiler. Both standards prohibit the use
of unlined masonry construction as a chimney, with
the exception in ANSI Z223.1/NFPA 54 that "Where
permitted by the authority having jurisdiction,
existing chimneys shall be permitted to have their
use continued when an appliance is replaced by an
appliance of similar type, input rating, and
efciency." ANSI/NFPA 211 prohibits the use of
single wall metal vent as a chimney, while ANSI
Z223.1 allows it under very restrictive conditions.
In Canada refer to the Natural Gas and LP
Installation Code, CAN/CSA-B149.1.
B. Do not connect into same leg of chimney serving an
open replace.
C. Inspect chimney for obstructions or restrictions and
remove. Clean chimney if necessary.
D. Vent pipe to chimney must not be smaller than outlet
on draft hood or damper. Although single wall vent
pipe may be used, Type B is recommended. The
venting system must be arranged so that only the
boiler is served by the damper device. Installation
per paragraph 12 complies with this provision.
E. Where two or more appliances vent into a common
vent, the area of the common vent should at least
equal the area of the largest vent plus 50% of the
area in the additional vents. Do not connect the vent
of this appliance into any portion of mechanical
draft system operating under positive pressure.
F. Vent pipe should have the greatest possible initial
rise above the draft hood consistent with the head
room available and the required clearance from
adjacent combustible building structure. Vent Pipe
should be installed above the bottom of chimney to
prevent blockage.
G. Vent pipe should slope upward from draft hood to
chimney not less than one inch in four feet. Doivent
présenter des tronçons horizontaux dont la pente
montante est d’au moins ¼ po par pied (21 mm/m)
entre la chaudière et l’évent. No portion of vent
pipe should run downward or have dips or sags.
Vent pipe must be securely supported. Les sections
horizontales doivent être supportées pour prévenir le
échissement.
H. Vent pipe must be inserted into but not beyond
inside wall of chimney liner. Seal tight between vent
pipe and chimney.
I. Do not install non-listed (AGA, CGA, CSA, ETL or
UL) vent damper or other obstruction in vent pipe.
WARNING
14. IF AN EXISTING BOILER IS REMOVED -
When an existing boiler is removed from a common
venting system, the common venting system is likely to
be too large for proper venting of the appliances
remaining to it.
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:
A. Seal any unused openings in the common venting
system.
B. 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.
C. 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 appliance
not connected to the common venting system. Turn
on any exhaust fans, such as range-hoods and
bathroom exhausts, so they will operate at maximum
Figure 8: Typical Vent Installation

11
speed. Do not operate a summer exhaust fan. Close
replace dampers.
D. Place in operation the appliance being inspected.
Follow the Lighting (or Operating) Instructions.
Adjust thermostat so appliance will operate
continuously.
E. 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.
F. After it has been determined that each appliance
remaining connected to the common venting system
properly vents when tested as outlined above, return
doors, windows, exhaust fans, replace dampers and
any other gas burning appliance to their previous
conditions of use.
G. Any improper operation of the common venting
system should be corrected so the installation
conforms with the National Fuel Gas Code, ANSI
Z223.1 and/or CAN/CSA B149.1, Installation
Codes. When resizing any portion of the common
venting system, the common venting system should
be resized to approach the minimum size as
determined using the National Fuel Gas Code,
ANSI Z223.1 and/or CAN/CSA B149.1, Installation
Codes.
Au moment du retrait d’une chaudière existante, les
mesures suivantes doivent être prises pour chaque
appareil toujours raccordé au système d’evacuation
commun et qui fonctionne alors que d’autres
appareils toujours raccordés au système
d’évacuation ne fonctionnent pas:
A. Sceller toutes les ouvertures non utilisées du
système d’évacuation.
B. Inspecter de facon visuelle le système d’évcuation
pour déterminer la grosseur et l’inclinaison
horizontale qui conviennent et s’assurer que le
système est exempt d’obstruction, d’étranglement,
de fuite, de corrosion et autres défaillances qui
pourraient présenter des risques.
C. Dans la mesure du possible, fermer toutes les portes
et les fenêtres du bâtiment et toutes les portes entre
l’espace où les appareils toujours raccordés au
système d’évacuation sont installés et les autres
espaces du bâtiment. Mettre en marche les
sécheuses, tous les appareils non raccordés au
système d’évacuation commun et tous les
ventilateurs d’extraction comme les hottes de
cuisinière et les ventilateurs des salles de bain.
S’assurer que ces ventilateurs fonctionnent à la
vitesse maximale. Ne pas faire fonctionner les
ventilateurs d’été. Fermer les registres des
cheminées.
D. Mettre l’appareil inspecté en marche. Suivre les
instructions d’allumage. Régler le thermostat de
facon que l’appareil fonctionne de facon continue.
E. Faire fonctionner le brùleur principal pendant 5 min
ensuite, déterminer si le coupe-tirage déborde à
l’ouverture de décharge. Utiliser la amme d’une
allumette ou d’une chandelle ou la fumée d’une
cigarette, d’un cigare ou d’une pipe.
F. Une fois qu’il a été déterminé, selon la méthode
indiquée ci-dessus, que chaque appareil raccordé au
système d’évacuation est mis à l’air libre de facon
adéquate. Remettre les portes et les fenêtres, les
ventilateurs, les registres de cheminées et les
appareils au gaz à leur position originale.
G. Tout mauvais fonctionnement du système
d’évacuation commun devrat être corrigé de facon
que l’installation soit conforme au National Fuel
Gas Code, ANSI Z223.1 et (ou) aux codes
d’installation CAN/CSA-B149.1. Si la grosseur
d’une section du système d’évacuation doit être
modiée, le système devrait être modié pour
respecter les valeurs minimales des tableaux
pertinents de l’appendice F du National Fuel Gas
Code, ANSI Z223.1 et (ou) des codes d’installation
CAN/CSA-B149.1.
15. INSTALL A ROOM THERMOSTAT on an inside
wall about four feet above oor. Never install
thermostat on an outside wall or where it will be
inuenced by drafts, hot or cold water pipes, lighting
xtures, television, rays of the sun or near a replace.
Keep large furniture away from thermostat so there will
be free movement of room air around this control.
Table 4: Wiring Diagrams and Heat Anticipator Settings
Ignition Type Circulation Method Thermostat Heat Anticipator
Setting [Amps]
Wiring
Diagram Figure
Continuous
(Standing Pilot)
Intermittent 0.6 11
Constant/Gravity 1.0 14
Electronic
Intermittent 0.6 12
Constant/Gravity 1.0 15
If system tends to overheat above thermostat's temperature setting, reduce heat anticipator setting by
0.1 or 0.2 amps. If system tends to shortcycle without reaching desired room temperature, increase heat
anticipator setting by 0.1 or 0.2 amps.

12
Figure 9: Vent Damper Schematic Wiring Diagram
Heat Anticipator in Thermostat should be set to match
the requirements of the control to which it is connected.
See Table 4. If system tends to overheat above the
thermostat's temperature setting, reduce heat anticipator
setting by .1 or .2 amps. If system tends to short cycle
without reaching desired room temperature, increase
heat anticipator setting by .1 or .2 amps.
16. INSTALL ELECTRIC WIRING in accordance with
National Electric Code or the Canadian Electrical Code
and local regulations. See Figures 11 through 16 for
applicable wiring diagram. A separate electrical circuit
must be run from the main electrical service with an
over-current device/disconnect in the circuit. A service
switch is recommended and may be required by some
local jurisdictions. When installed, the boiler must be
electrically grounded in accordance with local codes or,
in the absence of local codes, with the National
Electrical Code, ANSI/NFPA 70, and/or the CSA C22.1
Electrical Code, if an external electrical source is
utilized.
For zone valve wiring, a separate 24V transformer is
required rather than attempting to use the boiler
mounted control. Consult zone valve manufacturer for
assistance.
17.VENT DAMPER SEQUENCE OF OPERATION.
See Figure 9.
A. The Vent Damper is continuously powered at
Terminal 1.
B. When there is a call for heat, the damper relay coil is
energized through Terminal 5 if all limits ahead of
the damper are satised.
C. The relay coil closes contacts which energize the
damper motor, causing the damper to open.
D. When the damper blade reaches the fully open
position, power is sent back to the ignition circuit
through Terminal 2 and the damper motor is de-
energized.
E. When the call for heat is satised, the damper relay
coil is de-energized - closing contacts which
energize the damper motor. This causes the damper
to close. When the damper blade reaches the fully
closed position, the damper motor is de-energized.
POWER FAILURE - The damper blade will stop in
the position it was in when power failed.
(Combustion can never take place unless the damper
blade is in the fully open position.)
CAUTION
This boiler contains controls which may cause the boiler to shut down and not restart without service. If
damage due to frozen pipes is a possibility, the heating system should not be left unattended in cold weath-
er; or appropriate safeguards and alarms should be installed on the heating system to prevent damage if
the boiler is inoperative.
CAUTION
Avoid operating this boiler in an environment where saw dust, loose insulation bers, dry wall dust, etc.
are present. If boiler is operated under these conditions, the burner interior and ports must be cleaned and
inspected daily to insure proper operation.

13
SEQUENCE OF OPERATION
Normal Operation
1. When the thermostat call for heat, the vent damper
will open (see paragraphs 17A through 17D). The
circulator is started through a relay and at the same
time the gas valve is energized allowing main gas
ow and ignition of main burners.
2. Where condensation of ue gas is encountered in
boiler ues a reverse acting circulator control should
be installed to stop the circulator before the boiler
water temperature drops to that which ue gas
condensation may occur.
3. After the thermostat is satised the main valve will
close and main burner ames will be extinguished.
The vent damper will close (see paragraph 17E).
SAFETY SHUTDOWN
1. High Limit Switch
In the event excessive boiler water temperature is
developed the high limit switch will open
interrupting power to the gas valve. The main
burners will be extinguished immediately, and the
vent damper will close at the same time, but the
circulator will continue to operated. Normal
operation will be resumed when the boiler water
temperature drops to a point where the high limit
switch closes.
Figure 11: Wiring Diagram, 24 Volt Standing Pilot and Intermittent Circulation
2. Blocked Vent Switch
In the event excessive blockage in the vent system is
developed the blocked vent switch will open
interrupting power to the gas valve. The main
burners will be extinguished immediately, the
circulator will continue to operate, and the vent
damper will remain open until the thermostat is
turned off. The source of blockage must be
corrected by trained and skilled personnel from a
qualied service agency before resetting switch.
3. Flame Rollout Switch
In the event excessive blockage in the boiler section
ue passageways is developed the ame rollout
switch will open interrupting power to the gas valve.
The main burners will be extinguished immediately,
the circulator will continue to operate and the vent
damper will remain open until the thermostat is
turned off. If the ame rollout switch is activated do
not attempt to place the boiler in operation. The
source of blockage must be corrected and the ame
rollout switch replaced by trained and skilled
personnel from a qualied service agency.
4. Pilot
The thermocouple proves pilot ame and in the
absence of such within 45-90 seconds causes the
combination gas valve, which is equipped with a
100% shut-off provision, to be de-energized, thus,
preventing main gas or pilot gas ow.

14
Figure 12: Wiring Diagram, Electronic Ignition (EI), Intermittent Circulation
SEQUENCE OF OPERATION
NORMAL OPERATION
1. When the thermostat calls for heat, the relay is
energized. The circulator starts and the vent damper
opens (see Paragraphs 17A through 17D). When the
damper blade reaches the fully open position, the
ignition module is energized opening the pilot valve
and energizing the igniter to ignite the pilot burner.
2. Sensor proves presence of pilot ame. Main valve
opens to ignite main burners.
3. The burners and circulator will operate
simultaneously until the thermostat is satised.
4. After thermostat is satised, ignition module is de-
energized, extinguishing pilot and main ame. Vent
damper closes (see paragraph 17E).
SAFETY SHUTDOWN
1.Limit: Automatically interrupts main burner
operation when water temperature exceeds set point.
Maximum allowable temperature is 250°F. Normal
operation resumes when water temperature falls
below set point.
2.Blocked Vent Switch: Automatically interrupts
main burner operation when excessive vent system
blockage occurs. Control is a multiple use device. If
blocked vent switch is activated do not attempt to
place boiler in operation. Correct source of blockage
and reset blocked vent switch.
3.Flame Roll-out Switch: Automatically interrupts
boiler operation when ames or excessive heat are
present in vestibule. Control is single use device. If
ame roll-out switch is activated do not attempt to
place boiler in operation. Correct source of blockage
and replace ame roll-out switch.
4. Igniter/Sensor: senses pilot ame and causes
ignition module to turn off main burner and pilot
burner gas ow should pilot burner ame
extinguish. Five to six minutes after shutdown,
ignition module restarts ignition sequence.
5. For Electronic Ignition Trouble Shooting Guide, see
Page 25 of this manual.

15
Figure 13: Wiring Diagram, 24 Volt Standing Pilot with Continuous or Gravity Circulation
SEQUENCE OF OPERATION
NORMAL OPERATION
1. When the thermostat call for heat, the vent damper
will open (see paragraphs 17A through 17D). The
gas valve is energized allowing main gas to ow and
operation of the main burners.
2. Where condensation of ue gas is encountered in
boiler ues a reverse acting circulator control should
be installed to stop the circulator before the boiler
water temperature drops to that which ue gas
condensation may occur.
3. After the thermostat is satised the main valve will
close and main burner ames will be extinguished.
The vent damper will close (see paragraph 17E). If
the boiler is so equipped, circulator will continue to
run.
SAFETY SHUTDOWN
1. High Limit Switch: In the event excessive boiler
water temperature is developed the high limit switch
will open interrupting power to the gas valve. The
main burners will be extinguished immediately.
Normal operation will be resumed when the boiler
water temperature drops to a point where the high
limit switch closes.
2. Blocked Vent Switch: In the event excessive
blockage in the vent system is developed the
blocked vent switch will open interrupting power to
the gas valve. The main burners will be extinguished
immediately and the vent damper will remain open
until the thermostat is turned off. The source of
blockage must be corrected by trained and skilled
personnel from a qualied service agency before
resetting switch.
3. Flame Rollout Switch: In the event excessive
blockage in the boiler section ue passageways is
developed the ame rollout switch will open
interrupting power to the gas valve. The main
burners will be extinguished immediately and the
vent damper will remain open until the thermostat is
turned off. If the ame rollout switch is activated do
not attempt to place the boiler in operation. The
source of the blockage must be corrected and the
ame rollout switch replaced by trained and skilled
personnel from a qualied service agency.
4. Pilot: The thermocouple proves pilot ame and in
the absence of such within 45-90 seconds causes the
combination gas valve, which is equipped with a
100% shut-off provision, to be de-energized, thus,
preventing main gas or pilot gas ow.

16
Figure 14: Wiring Diagram, Electronic Ignition (EI), Continuous or Gravity Circulation
SEQUENCE OF OPERATION
NORMAL OPERATION
1. When the thermostat calls for heat the vent damper
opens (see Paragraphs 17A through 17D). When the
damper blade reaches the fully open position, the
ignition module is energized opening the pilot valve
and energizing the igniter to ignite the pilot burner.
2. Sensor proves presence of pilot ame. Main valve
opens to ignite main burners.
3. The burners will operate until the thermostat is
satised.
4. When thermostat is satised, ignition module is de-
energized, extinguishing pilot and main ame. If
boiler is equipped with circulator, circulator will
continue to run. Vent damper closes (see Para-graph
17E).
SAFETY SHUTDOWN
1.Limit: Automatically interrupts main burner
operation when water temperature exceeds set point.
Maximum allowable temperature is 250°F. Normal
operation resumes when water temperature falls
below set point.
2.Blocked Vent Switch: Automatically interrupts
main burner operation when excessive vent system
blockage occurs. Control is a multiple use device. If
blocked vent switch is activated do not attempt to
place boiler in operation. Correct source of blockage
and reset blocked vent switch.
3.Flame Roll-out Switch: Automatically interrupts
boiler operation when ames or excessive heat are
present in vestibule. Control is single use device. If
ame roll-out switch is activated do not attempt to
place boiler in operation. Correct source of blockage
and replace ame roll-out switch.
4. Igniter/Sensor: senses pilot ame and causes
ignition module to turn off main burner and pilot
burner gas ow should pilot burner ame
extinguish. Five to six minutes after shutdown,
ignition module restarts ignition sequence.
5. For Electronic Ignition Trouble Shooting Guide, see
Page 25 of this manual.

17
Figure 15: Wiring Schematic, Zone Valves
Figure 16: Wiring Schematic, Zone Circulators

18
II. Operating Instructions
1. MAIN BURNER CHECK - Check main burners to
see that they were not dislodged during shipment. Rear
of burners should be in the slots in the rear of burner
tray and the front of the burners should be seated
completely on the orices.
2. INITIAL START -
A. FILL ENTIRE HEATING SYSTEM WITH
WATER and vent air from system. Use the
following procedure on a Series Loop System
equipped with zone valves. (See Figure 3).
1. Close isolation valve in boiler supply piping.
2. Isolate all circuits by closing zone valves or
balancing valves.
3. Attach a hose to hose bib located just below
isolation valve in boiler supply piping. (Note -
Terminate hose in ve gallon bucket at a suitable
oor drain or outdoor area).
4. Starting with one circuit, open zone valve.
5. Open hose bib.
6. Open ll valve (Make-up water line should be
located directly above isolation valve in boiler
supply piping).
7. Allow water to overow from bucket until
discharge from hose is bubble free for 30
seconds.
8. Open zone valve to the second zone to be
purged, then close the rst. Repeat this step until
all zones have been purged, but always have one
zone open. At completion, open all zone valves.
9. Close hose bib, continue lling the system until
the pressure gauge reads 12 psi. Close ll valve.
(Note - If make-up water line is equipped with
pressure reducing valve, system will
automatically ll to 12 psi. Leave globe valve
open).
10. Open isolation valve in boiler supply piping.
11. Remove hose from hose bib.
B. Turn ROOM THERMOSTAT to lowest setting.
C. Be sure that gas to pilot and main burners has been
off for at least ve minutes and vent damper (if
used) has been in the open position.
D. Turn "OFF" the electric switch serving boiler.
E. Open valve on main gas line at meter.
F. PURGE AIR FROM GAS PIPING. This
procedure will vary with equipment furnished but in
all cases adequate ventilation must be provided
and no smoking or open ame permitted. To
determine which of the procedures outlined in
succeeding paragraphs is applicable, match sufx of
Figure 17: Schematic Pilot and Gas Piping
Continuous Ignition (Standing Pilot)
Figure 18: Schematic Pilot and Gas Piping
Electronic Ignition (EI)
boiler model found on Rating Label with paragraph
heading:
1. Standing Pilot Models (Sufx C):
a. Keep electric switch "OFF".
b. Open Manual Shut-off Valve upstream of
Combination Gas Valve.
c. Disconnect Pilot Tubing at gas valve (Purge
must not be into combustion chamber).
d. Turn Main Gas Knob on Combination Gas
Valve to "Pilot" Position. Depress and hold
in this position until purging is complete.
Turn Main Gas Knob to "off" position.
Safe lighting and other performance criteria were met with the gas manifold and control assembly provided on the boiler when the
boiler underwent tests specied in American National Standard for Gas-Fired Low-Pressure Steam and Hot Water Boilers, ANSI
Z21.13b-1994.

19
Figure 20: Operating Instructions, VR8204 and VR8304 Gas Valves
Figure 19: Top View of VR Gas Valves

20
e. Reconnect pilot tubing and check pipe
and ttings from meter to combination
Gas Valve for leaks using soap
solution or other approved method.
2. Electronic Ignition Models (Sufx I):
a. Turn "ON" electric switch serving
boiler.
b. Open Manual Shut-off Valve upstream
of Combination Gas Valve.
c. Loosen or remove Inlet Pressure Tap
Plug in Combination Gas Valve and
when purging is complete, tighten or
replace plug. See Figure 19.
d. Check pipe and ttings from meter to
Combination Gas Valve using soap
solution or other approved methods.
CAUTION
e. Test gas piping and connections
between Combination Gas Valve and
manifold, orices, and pilot piping for
leaks after boiler is operating. Use
soap solution or other approved
method.
3.INSTRUCTIONS TO PUT THE BOILER IN
OPERATION.
A. See Figure 20 for electronic ignition (EI).
Electronic Ignition Modules with LED
indicators. Table 5 cross-references the
ignition module terminal designations to the
ignition terminal numbers in the wiring ladder
diagrams. Table 6 provides green LED status
codes and recommended service action where
applicable.. See Figure 21A for Location of
LED. See Figure 28 for Troubleshooting
Guide.
1. Flame Current Measurement Procedure.
See Figure 21B “Measuring pilot ame
current with micro-ammeter”
a. Pilot ame current in micro amps can
be measured using any standard
micro-ammeter by inserting the meter
probes into the module holes labeled
FLAME CURRENT as shown in
Figure 21B.
b. Flame current must be measured
with pilot valve open/pilot lit but the
main valve closed.
c. Disconnect MV lead wire from the
module before measuring ame
current. Trying to measure the pilot
ame current in series with the wiring
will not yield the accurate reading.
Figure 21A: Location of LED
Table 5: Ignition Module Terminal Cross-Reference
Figure 21B: Measuring Pilot Flame Current
with Micro-ammeter
Ignition Module
Terminal Designation
Wiring Ladder Diagram
Terminal Number
MV 1
MV/PV 2
PV 3
GND 4
24V (GND) 5
24V 6
SPARK 9