Dunkirk DPFG Series User manual

! !
SUPPLEMENTALVENTINGINSTRUCTION
CASTIRONPRESSURE-FIRED
WETBASEHOTWATERBOILERS
P/N 240005665, Rev. 1.1 [05/06]
! !
! !
Tested For 100 LBS.
ASME
Working Pressure
C.S.A. Certified
For Natural Gas Or Propane
CAUTION
Do not use this vent pipe or fittings for vent-
ing incinerators of any kind.
WARNING
For correct installation of your venting sys-
tem, read all of these instructions and refer
to the vent pipe manufacturer’s instructions.
Failure to use a proper venting system will
void the manufacturer’s warranty and may
result in rapid deterioration of the venting
system, a potential health hazard.
Faulty vent installation can allow toxic
fumes to be released into living areas. This
may cause serious bodily injury or property
damage. Vent performance may also be af-
fected by improper assembly.
Install separate vents for forced exhaust
appliances and natural draft appliances.
A common vent between natural draft and
forced exhaust appliances may cause toxic
gases to exhaust through the natural draft
appliance rather than to the outside air.
Breathing exhaust gases will cause serious
personal injury or death.
WARNING
All installations of boilers and venting should
be done ONLY by a qualifies expert and in
accordance with the appropriate manual. In-
stalling or venting a boiler or any other gas
appliance with improper methods or materi-
als may result in serious injury or death due
to fire or asphyxiation from poisonous gases
such as carbon monoxide which is odorless
and invisible.

3
! !
VENTING INSTRUCTIONS
P/N# 240005665, Rev. 1.1 [05/06]
FRESH AIR FOR COMBUSTION - CHIMNEY VENTED BOILERS
WARNING
Be sure to provide enough fresh air for
combustion. Enough air ensures proper
combustion and assures that no hazard will
develop due to the lack of oxygen.
Ventilation of the boiler room must be adequate to
provide sufficient air to properly support combustion
per the latest revision of the National Fuel Gas Code,
ANSI Z223.1, Section 5.3.
When a boiler is located in an unconfined space in a
building or conventional construction frame, masonry
or metal building, infiltration normally is adequate to
provide air for combustion and ventilation. However,
if the equipment is located in a building of unusually
tight construction (See the National Fuel Gas Code,
ANSI Z223.1, Section 1.7), the boiler area should be
considered as a confined space. In this case air for
combustion and ventilation shall be provided according
to Part 5. If there is any doubt, install air supply
provisions in accordance with the latest revision of the
National Fuel Gas Code.
You must provide for enough fresh air to assure proper
combustion. The fire in the boiler uses oxygen. It must
have a continuous supply. The air in a house contains
only enough oxygen to supply the burner for a short
time. Outside air must enter the house to replace that
used by the burner. Study following two examples to
determine your fresh air requirements.
BOILER IN UNCONFINED SPACE
If your boiler is in an open area (unpartitioned basement)
in a conventional house, the air that leaks through
the cracks around doors and windows will usually be
adequate to provide air for combustion. The doors
should not fit tightly. Do not caulk the cracks around
the windows.
An unconfined space is defined as a space whose
volume is not less than 50 cubic feet per 1,000 Btu per
hour of the total input rating of all appliances installed
in the space.
BOILER IN CONFINED SPACE
ALL AIR FROM INSIDE BUILDING: The confined
space shall be provided with two permanent openings
communicating directly with an additional room(s)
of sufficient volume so that the combined volume
of all spaces meets the criteria for an unconfined
space. The total input of all combustion equipment
installed in the combined space shall be considered
in making this determination. Each opening shall
have a minimum free area of one square inch per
1,000 Btu per hour of the total input rating of all
combustion equipment in the confined space but not
less than 100 square inches. One opening shall be
within 12 inches of the top and one within 12 inches
of the bottom of the enclosure. See Figure #1.
Example: Your boiler is rated at 100,000 Btu per
hour. The water heater is rated at 30,000 Btu per
hour. The total is 130,000 Btu per hour. You need
two grilles, each with 130 square inches of FREE
opening. Metal grilles have about 60% FREE
area. To find the louvered area needed, multiply
the FREE area required by 1.7 (130 x 1.7 = 221.0
sq. in. louvered area). In this example, two grilles,
each having an 8” x 30” (240 sq. in.) louvered
area would be used. Figure 1 shows the grille
locations.
ALL AIR FROM OUTDOORS: The confined space
shall be provided with two permanent openings, one
commencing within 12 inches of the top and one
commencing within 12 inches of the bottom of the
enclosure. The openings shall communicate directly,
FIG. 1 – AIR OPENINGS FOR CLOSET OR UTILITY
ROOM INSTALLATIONS

4
! !
or by ducts, with the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors.
1. When communicating with the outdoors
directly or through vertical ducts, each opening
shall have a minimum free area of one square
inch per 4,000 Btu per hour of total input rating of
all equipment in the enclosure.
NOTE: If you use a fireplace or a kitchen or bathroom exhaust
fan, you should install an outside air intake. These devices
will rob the boiler and water heater of combustion air.
2. When communicating with the outdoors
through horizontal ducts, each opening shall
have a minimum free area of one square inch
per 2,000 Btu per hour of total input rating of all
equipment in the enclosure.
3. When ducts are used, they shall be of the
same cross-sectional area as the free area of the
openings to which they connect. The minimum
dimension of rectangular air ducts shall be not
less than three inches.
FRESH AIR DUCT CAPACITIES
The following table shows fresh air duct capacities (in
Bthu) for ducts supplying fresh air to boilers in tightly
Fresh Air
Duct Size
Duct Covering
¼” Mesh
Screen
Wood
Louver
Metal
Louver
3½” x 12” 144,000 36,000 108,000
8” x 8” 256,000 64,000 192,000
8” x 12” 384,000 96,000 288,000
8” x 16” 512,000 128,000 384,000
FIG. 2 – FRESH AIR DUCTS FOR TIGHTLY SEALED
HOUSES
FLUE CONNECTIONS
constructed houses (based on openings covered by ¼”
mesh screen, wood louvers, or metal louvers):
APPLICABLE FEDERAL CODES
NFPA 54/ANSI Z223.1, National Fuel Gas Code (Part
7) and NFPA/ANSI211, Chimneys, Fireplaces, Vents,
and Solid Fuel Burning Appliances. These codes
contain information on special gas vents for Category
II, III and IV appliances, vent sizing, location, air space
clearances to combustibles and safe installation
practices. The gas vent installer should be familiar
with these Federal Codes as well as Local Codes and
Regulations.
GENERAL INFORMATION -
GAS VENTS & APPLIANCES
By federal codes, gas appliances are categorized by
the pressure and temperature of the flue gas vented
from the appliance. Category I and II appliances are
natural draft (draft hood) vented, with high flue gas
temperatures (Category I) and low flue gas temperatures
(Category II). Category III and IV appliances are fan
forced vents with high temperature (Category III) and
low temperature (Category IV) flue gasses. Appliance
efficiency is directly related to flue gas temperature.
Higher efficiency appliances remove more heat from
the gas, so they will have lower temperature flue
products. When flue gas temperatures are lowered,
corrosive condensates may form in Category II, III, IV
appliance vents, so special, corrosive resistant venting
systems are required for higher efficiency appliances.
WARNING
Vents for Category I appliances may not
be suitable for use with Category II, III, or
IV appliances because condensate may
corrode the vent.
Vents for Category III appliances may not be
suitable for use with Category I appliances
because flue gas temperatures may be too
high.
Proper operation of the vent system and
appliance is dependent upon the use of all
parts specified by the manufacturer for use
in the particular installation. Appliance and
vent system performance may be affected by
improper assembly.
See this manual for vent pipe installation
and components.

5
! !
IMPORTANT
For gas-fired boilers for connection to gas
vents or chimneys, vent installations shall be in
accordance with Part 7, “Venting of Equipment,” of
the National Fuel Gas Code, ANSI Z223.1/NFPA-
54, or Section 7, “Venting Systems and Air Supply
for Appliances,” of the CAN/CSA B149.1, Natural
Gas and Propane Installation Code, and applicable
provisions of local building codes.
For oil-fired boilers for connections to vents or
chimneys, vent installations shall be in accordance
with applicable provisions of “Installation of Oil,
Burning Equipment” NFPA-31 – latest revision, and
applicable provisions of local building codes.
WARNING
Boiler is to be vented by natural draft and
shall not be connected into any portion of a
mechanical draft system operating under a
positive pressure.
Inspect chimney to make certain it is
constructed according to the latest revision
of the NFPA211. Local codes may differ from
this code and should be checked. Where
there is a conflict, the local code will prevail.
In Canada refer to the National Building
Code or CSA-A405 as applicable.
When the boiler is removed from the common venting
system, test to see if the vent system is too large for
the remaining appliance. 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 any unused openings 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 deficiencies 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 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
speed. Do not operate a summer exhaust fan. Close
fireplace 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 flame 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 the common venting system
properly vents when tested as outlined above,
return doors, windows, exhaust fans, fireplace
dampers and any other gas-burning appliance 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 CAN/CSA B149.1, Natural
Gas and Propane Installation Code. 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 appropriate tables in Part 11 of the National Fuel
Gas Code, ANSI Z223.1/NFPA 54 and/or CAN/CSA
B149.1, Natural Gas and Propane Installation Code.

6
! !
! !
! !
NOTE: If boiler is to be direct exhausted through a wall of the
boiler room, please see next page.
WARNING
All installations of boilers and venting
should be done only by a qualified expert
and in accordance with the appropriate
manual. Installing or venting a boiler or any
other gas appliance with improper methods
or materials may result in serious injury
or death due to fire or asphyxiation from
poisonous gases such as carbon monoxide,
which is odorless and invisible.
CHIMNEY VENT INSTALLATION (CATEGORY I)
WARNING
This boiler shall not be connected to any
portion of a mechanical draft system
operating under positive pressure.
1. Horizontal portions of the venting system shall be
supported rigidly every 5 feet and at the elbows. No
portion of the vent pipe should have any dips or sags.
2. This boiler series is classified as a Category I and the
vent installation shall be in accordance with chapters 7
and 10 of the National Fuel Gas Code noted above or
applicable provisions of the local building codes.
3. Inspect chimney to make certain it is constructed
according to NFPA 211. The vent or vent collector 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).
4. Connect flue 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 flue pipe or reduce size
of flue outlet except as provided by the latest revision
of ANSI Z223.1. Protect combustible ceiling and walls
near flue pip with fireproof insulation. Where two or
more appliances vent into a common flue, the area of
the common flue must be at least equal to the area
of the largest flue plus 50 percent of the area of each
additional flue.
INDOOR CHIMNEY VENTED BOILERS
! !
WARNING
Do not connect this Category 1 boiler to a
vent system used by a Category III and IV
appliance. Do not connect it to vents with
mechanical draft systems operating at
positive pressure. Improper venting could
allow combustion products to collect in the
structure during use, resulting in damage,
injury, or death.
CHIMNEY LINING
Use a suitably sized Type B1 vent liner or suitable
corrugated liner.
WARNING
Support vent liner in a masonry chimney.
Maintain at least 1” clearance on all sides to
reduce the possibility of condensate in vent.
Condensate may cause vent to deteriorate,
allowing combustion products to collect in the
structure, which could result in injury or death.
Vent liner must not block opening where
vent connectors from other appliance enter
the chimney. Blocked openings will cause
combustion products to collect in the structure,
resulting in damage, injury, or death.
Do not use unlined masonry chimneys. These
increase risk of condensate formation, which
may cause the chimney to deteriorate, allowing
combustion products to collect in the structure,
resulting in damage, injury, or death.
1. The following chart shows recommended
minimum chimney sizes based the I=B=R Testing
and Rating Standard for Heating Boilers.
Firing
Rate (gph)
Chimney
Height*
Nominal
Chimney
Area
Round
Liner Inside
Diameter
Square
Liner Inside
Dimensions
0.6 - 1.3
1.31 - 1.8
1.81 - 2.0
2.1 - 3.0
15’
15’
20’
20’
8” x 8”
8” x 8”
8” x 8”
8” x 12”
6”
7”
8”
10”
6¾” x 6¾”
6¾” x 6¾”
6¾” x 6¾”
6½” x 10½”
* For elevations above 2,000 feet above sea level, add 3 feet to
chimney heights.

7
For additional chimney design and sizing information,
consult the ASHRAE HVAC Systems and Applications
Handbook, “Chimney, Gas Vent, and Fireplace
Systems,” of the National Standard for Chimneys,
Fireplaces, Vents and Solid Fuel Burning Appliances,
ANSI/NFOA 211.
2. A draft regulator is recommended with or without
a neutral pressure point adjustor in all cases where
there is chimney draft present. When flue is under
positive pressure, such as with a through-the-wall
vent, a draft regulator is not used. When a draft
regulator is used, it should be the same diameter as
the smoke pipe.
For gas units, a double-acting draft regulator is
preferable to a draft diverter. All vent pipe joints and
seams operating under positive pressure must be
sealed gas tight with minimum 400 F RTV Silicone
Rubber Adhesive Sealant. Category III Special
Venting System is required.
3. Where draft is present, adjust draft regulator
to maintain .01 in breeching. See “Controlling
Excessive Draft” and Figure #3 on this page for
instructions on controlling excessive draft by means
of a neutral pressure point adjuster.
4. Slope pipe up from boiler to chimney not less
than ¼” per foot.
5. Run pipe as directly as possible with a minimum
number of elbows.
6. Do not connect to fireplace flue.
7. The end of flue pipe must be flush with the inside
face of chimney flue.
8. Support the flue pipe rigidly with substantial
hangers plus three sheet metal screws at each pipe
joint.
9. The chimney should extend at least two feet
above any object within 10 feet and extend at least
three feet higher than roof at point of exit.
10. Particular attention should be paid to the point
where the flue passes through a wall or ceiling. Such
penetration should always be made in accordance
with prevailing code requirements.
CONTROLLING EXCESSIVE DRAFT
A neutral pressure point adjuster will reduce excessive
draft-regulator air flow which can cause condensation
and chimney damage. If draft regulator must be more
than slightly open to maintain draft at .01 at breeching,
a neutral pressure point adjuster should be installed
between the boiler flue collar and the draft regulator.
Insert adjuster so that draft regulator is not more than
slightly open to maintain draft at .01 in breeching. The
adjuster should be constructed so that it is permanently
locked in place and cannot be moved accidentally in
a manner that will interfere with normal operation of
the burner. Do not lock adjuster in place until burner
firing rate has been established and burner has been
adjusted to normal operating conditions.
FIG. 3 – CONTROLLING EXCESSIVE DRAFT WITH A NEUTRAL PRESSURE POINT ADJUSTER

8
! !
INDOOR DIRECT EXHAUST BOILERS
— FOR OIL-FIRED BOILERS ONLY!! —
WARNING
Do not vent a gas-fired boiler through a side
wall. Gas-fired boilers may only be vented
into a chimney (Category I).
Consult with local authorities to ensure
compliance with all building, plumbing, and
electrical codes.
The optional DES is to be used in conjunction with the
boiler for indoor installations requiring through-the-wall
venting. The DES is designed as an integral part of the
boiler, eliminating the need for a power venter.
Oil boiler DES kits include an oil burner with adjustable
post purge timer and solenoid valve. For through-the-wall
venting, the post purge burner must be used in place of
the standard burner that is furnished with the boiler.
NOTE: Use standard single wall galvanized metal vent pipe for
the vent and air intake piping. A B-Vent shall not be used in the
vent system.
The exhaust terminal included in the FDVS kit is a
model FDVS stainless steel vent hood. Located on
an exterior wall of the building, the exhaust terminal
is one of the most important elements of a direct-vent
installation. Planning the location of the terminal is the
first step. See Figures #4 and #5.
The model FDVS vent hood is designed for use on
combustible walls up to 8” thick. For combustible walls
over 8” thick, consult the boiler manufacturer. The
FDVS vent hood may be used on non-combustible
walls of any thickness.
IMPORTANT: The FDVS side-wall vent hood re-
quires a ½” clearance to combustibles for flue gas
temperatures of 450°F or lower and a 1” clearance
for temperatures between 450° and 550°F. For flue
gas temperatures in excess of 550°F, use of a power
venter with the vent hood is recommended.
Boiler Kit Duct Dia. Wall
Opening
3 sections FDVS 4 4” 6½”
4 to 9 sections FDVS 6 6” 8½”
FIG. 4 – TYPICAL DIRECT EXHAUST INSTALLATION (W/BECKETT AFG OIL BURNER)

9
! !
LOCATION
The exhaust terminal must be positioned:
so that spent gases will freely disperse without
re-entering the building.
to permit smoke pipe from the boiler to slope
upward not less than ¼” per foot with no more
than a 6’ horizontal run.
in correct relationship to the combustion air inlet.
See paragraph 3 in the section titled “Intake Air”
for more information.
The exhaust terminal must not be located beneath a
porch or crawl space.
•
•
•
CAUTION
The importance of the exhaust terminal location
cannot be overemphasized. The exhaust terminal
must be located so that prevailing winds cause
exhausted flue products to disperse away from the
building. A stagnant area where exhaust products
can gather or a wind blowing exhaust products back
towards the building may cause undesirable odors
to enter the building through any available seams
or openings, including the vent itself. Exhaust
products blown back towards the building may
also cause discoloration of building materials. In
certain conditions, flue gas will condense and form
moisture. When this occurs, steps should be taken
to prevent building materials at the exhaust terminal
from being damaged by exhausted flue gas.
FIG. 5 – EXTERIOR EXHAUST TERMINAL LOCATIONS
NOTES: Location of the termination of the vent pipe shall
be in accordance with the National Fuel Gas Code; A.N.S.I.,
Z223.1 (see requirements below) and any local codes which
are applicable. Only one boiler may be exhausted through each
vent hood.
a. The exit terminals of mechanical draft systems shall not
be less than 7 feet above grade when located adjacent to
public walkways.
b. A venting system shall terminate at least 3 feet above any
forced air inlet located within 10 feet.
c. The venting system shall terminate at least 4 feet below,
4 feet horizontally from or 1 foot above any door, window or
gravity air inlet into any building.
d. An appliance with an input of over 50,000 BTU per hour
shall require a 12 inch vent termination clearance from any
opening. The bottom of the vent terminal and any air intake
shall be located at least 12 inches above grade level.
e. Forced draft systems shall be designed and installed so
as to prevent leakage of vent gasses into building.
f. The vent termination point shall not be installed closer
than 3 feet from an inside corner of an L-shaped structure.
g. Terminate the vent above normal snow line. Avoid
locations where snow may drift and block the vent. Ice or
snow may cause the boiler to shut down if the vent becomes
obstructed.

10
INSTALLATION
1. Use inside wall end plate as a template to mark hole
location. Cut hole 1 inch larger than marked hole to
facilitate easy installation.
2. Mount furnished 18” x 18” stainless steel plate
on the exterior side of the wall with appropriate type
mounting screws. Install vent hood through opening
from outside. Fasten the vent hood to the stainless
steel plate with appropriate type mounting screws.
Caulk as necessary.
3. Fasten wall end plate to the inside wall with
appropriate type mounting screws.
INTAKE AIR
1. Intake air is required to support combustion. It must
enter the same side of building as the exhaust vent
in order to balance wind pressure against the flow of
gases.
2. The bottom of the intake duct must be at least 1’
above grade level.
3. The intake duct and exhaust vent must be not less
than 4’ apart unless intake is at least 1’ below the level
of exhaust, in which case the intake may be at a radius
of 2’ or more from exhaust.
4. Provide a 4” wall opening and mount 4” intake duct
on a flat surface on exterior of wall in the same manner
as the exhaust terminal.
5. To supply intake air to the burner:
A. When a Beckett Model AFG oil burner is used,
run an air duct of 4” smoke pipe (not supplied) from
wall inlet directly to burner intake boot with vacuum
relief (draft regulator) installed in duct. Use a 4”
wrap-around coupling as provided to connect duct
to intake boot.
B. When a Beckett Model SMG oil burner or a
gas burner is used, run intake air duct (without
vacuum relief) from wall inlet down to an open end
approximately 1’ from boiler room floor.
C. When a vacuum relief is not used, note that
exhaust fans in use might create a vacuum within
the building which can cause improper combustion.
Consult factory for assistance as required.
D. See Figure #4 for typical installation with a
Beckett Model AFG post purge oil burner.
EXHAUST FLUE PIPE
The exhaust flue pipe from the boiler must be 6’ or less
in length in order to minimize condensation. Plan flue
pipe configuration to ensure easy disassembly for
cleaning of boiler interior.
1. Using silicone rubber, permanently cement a stub of
flue pipe 6” to 12” in length to the boiler flue collector. For
ease in later disassembly, use a wrap-around coupling
as provided to connect the stub to the next section of
flue pipe. Connect the remainder of flue pipe in normal
fashion.
2. Run flue pipe as directly as possible with a minimum
number of elbows. Two 45° elbows will cause less
resistance than one 90° elbow.
3. Particular attention should be paid to any point where
the flue pipe passes through a wall or ceiling. Such
penetrations should always be made in accordance
with existing code requirements.
4. At reduced flue pipe sizes, do not use more than two
90° elbows or four 45° elbows, and do not reduce pipe
to less than:
5. Support flue pipe rigidly with substantial pipe hangers
plus three sheet metal screws at each joint.
6. Seal pipe joints carefully with minimum 400°F RTV
silicone sealant or its equal so that no leakage can be
detected by the movement of smoke or a small flame
held near the joints with burner in operation.
IMPORTANT: Advise owner keep air intake free of
obstruction, both indoors and outdoors. Ventilating
and combustion air must enter boiler room and
burner without restriction.
Firing Rate Min. Pipe Diameter
less than 1.00 gph 4”
more than 1.00 gph 6”

11
ALTERNATE UNDERGROUND VENT
When the structure of the house or the exterior grade does not allow location of the vent terminal in compliance
with the instructions in this manual, an alternative is to vent into a clay pipe system installed underground. Refer
to notes in Figure 6 (below).
NOTES:
1. Clay chimney topper, tee, and pipe are manufactured by
Superior Clay Corp., P.O. Box 352, Uhlrichsville, Ohio, 44683.
Clay chimney top devices and pipe from other sources may be
used.
2. Clay pipe must pitch downward away from foundation ⅛” to
¼” per foot.
3. Configuration of transition from tee to topper is dependent
on the type of the topper selected and the level of the finished
grade. Topper must be removable for cleaning.
FIG. 6 – TYPICAL UNDERGROUND VENT INSTALLATION
4. Seal opening in foundation around clay pipe with hydraulic
cement.
5. Seal all joints and seams in smoke pipe with silicone rubber.
6. When tankless side of boiler must be next to wall, allow
enough distance (approx. 18”) to remove coil.
7. Do not use a draft regulator in flue pipe.
8. 6” flue sizes shown on diagram are appropriate for input up to
1.5 gph. 8” flue components may be used for larger firing rates.