Intelli-Fin 1 Manual

INSTALLATION AND SERVICE MANUAL
Intelli-Fin®
Hot Water Heating Boilers
Domestic Hot Water Supply Boilers
1,500,000 — 1,700,000 — 2,000,000 Btu/hr Models
IFB-IFW-I-S-06
FIG. 1 Front View FIG. 2 Rear View
Installation and service must be performed by a qualified service
installer, service agency or the gas supplier.
Factory warranty (shipped with unit) does not apply to units
improperly installed or improperly operated.
Experience has shown that improper installation or system design,
rather than faulty equipment, is the cause of most operating
problems.
1. Excessive water hardness causing a lime/scale
build-up in the copper tube is not the fault of the
equipment and is not covered under the
manufacturer’s warranty. (See Water Treatment and
Water Chemistry)
2. Excessive pitting and erosion on the inside of the
copper tube may be caused by too much water
velocity through the tubes and is not covered by
the manufacturer’s warranty (See Boiler Flow Rates
and Temperature Rise for flow requirements).
This manual supplies information for the installation, operation
and servicing of the appliance. It is strongly recommended that
this manual be reviewed completely before proceeding with an
installation.
WARRANTY
SPECIAL INSTRUCTIONS
TO OWNER
NOTE: Retain this manual for future reference.
WARNING
IMPROPER INSTALLATION, ADJUSTMENT,
ALTERATION, SERVICE OR MAINTENANCE can
cause injury or property damage. Refer to this manual. For
assistance or additional information, consult a qualified
installer, service agency or the gas supplier.
1

TABLE OF CONTENTS
Warranty .......................................................................... 1
Safety Warnings .............................................................. 3
Codes .......................................................................... 3
Installation Requirements ............................................ 4
Location .................................................................... 4
Clearances ................................................................ 4
Combustion/Ventilation Air Requirements .............. 5
Construction Air Filter .............................................. 7
Venting Systems ............................................................ 8
Category IV Venting ........................................................ 9
Flue Pipe Materials............................................ 9
Installation Guidelines ...................................... 9
Vent Length Requirements ................................10
Drain Tee Installation ........................................10
Vertical Terminations ........................................11
Sidewall Terminations ......................................12
Direct Vent Systems ........................................................13
Air Inlet Pipe Materials ....................................14
Air Inlet Pipe Length Requirements..................14
Vertical Direct Vent ..................................................15
Location Requirements......................................15
Multiple Direct Vent Installations......................16
Horizontal Direct Vent ..............................................16
Location Requirements......................................16
Multiple Direct Vent Installations......................18
Intelli-Vent Systems..................................................18
Materials ............................................................18
Length Requirements ........................................18
Vertical Flue - Sidewall Air ..............................19
Sidewall Flue - Rooftop Air ..............................20
Sidewall Flue - Sidewall Air..............................21
Gas Supply ....................................................................23
Gas Pressures and Piping ..................................23
Manifold Pressure..............................................23
Supply Pressure Measurement ..........................25
Manifold Pressure Measurement ......................26
Water Connections ..........................................................27
Heat Exchangers ..............................................................28
Integral Bypass ................................................................29
Valve and Pump ................................................29
Synchronization ................................................29
Set-up Maximum Flow......................................30
Bypass Operation ..............................................31
Minimum Water Temperatures ..................................31
Flow Switch ....................................................................32
Low Water Cut-Off ..........................................................32
Gas Train..........................................................................32
Relief Valve......................................................................33
Ratio Gas Valve ........................................................33
Diaphragm Gas Valve ..............................................33
Electrical Requirements ..................................................34
Jacket ..........................................................................34
Components and Controls ............................................35
Variable Frequency Drive..................................36
Low Air Pressure Switch ..................................37
Gas Pressure Switches ......................................37
Excel 10 Boiler Interface Controller ................37
Manual Override Control ..................................39
2
Temperature Adjustment....................................39
Command Display ............................................39
Password ....................................................40
Changeable Points ......................................40
Data Points in Display................................41
Status Points — Operation ........................43
Status Points — Alarm ..............................44
Outdoor Reset Function ............................44
Multiple Appliance Installations........................45
Sequencing Options....................................45
E-Bus Connection ......................................46
Temperature Limit Control................................48
Hot Surface Ignition Control ............................48
Hot Surface Igniter..............................49
Diagnostic Status LED........................49
Operation/Diagnostic Lights and Switches ......50
Burner Assembly ..............................................51
Combustion Air Blower ....................................52
Condensate Management System......................53
Installation and Operation ..................53
Condensate Trap Installation ..............54
Lighting Instructions ....................................................55
Sequence of Operation ..................................................57
Maintenance ............................................................57
Maintenance and Annual Startup..............................58
Vent System ............................................................58
Flame Patterns ..........................................................58
Condensate Testing ..................................................59
Burner Cleaning........................................................59
Heat Exchanger Inspection ......................................61
Lubrication ............................................................62
Combustion Air Measurements ................................62
Freeze Protection ......................................................63
Heating Boiler ............................................................64
Piping ............................................................64
Piping Length and Diameter ....................................65
Integral Pump Limitations ................................65
Boiler Pump Operation......................................65
Primary/Secondary Piping ................................66
Minimum Water Temperatures ..........................66
Three Way Valves ..............................................67
Boiler Flow Rates ..............................................67
Placing the Boiler in Operation ........................68
Boiler Temperature Control ..............................69
Water Heater/Domestic Hot Water Supply Boiler ....70
Typical Piping....................................................70
Set-up Maximum Flow......................................70
Temperature Rise ..............................................71
Water Chemistry ................................................72
Piping Requirements ........................................73
Pump Operation ................................................74
Temperature Adjustment....................................75
Minimum Inlet Temperatures ............................75
Risk of Scald Warnings ....................................76
Relief Valve ......................................................76
Ladder Diagram ............................................................77
Wiring Diagram ............................................................78
Revision Notes ..............................................Back Cover

Upon receiving equipment, check for signs of shipping damage.
Pay particular attention to parts accompanying the boiler, which
may show signs of being hit or otherwise being mishandled. Verify
total number of pieces shown on packing slip with those actually
received. In case there is damage or a shortage, immediately notify
carrier.
CHECKING EQUIPMENT
DO NOT
WARNING
Do not use this appliance if any part has been under water.
The possible damage to a flooded appliance can be extensive
and present numerous safety hazards. Any appliance that
has been under water must be replaced.
If the information in this manual is not followed exactly, a
fire or explosion may result causing property damage,
personal injury or loss of life.
This appliance MUST NOT be installed in any location
where gasoline or flammable vapors are likely to be present,
unless the installation is such to eliminate the probable
ignition of gasoline or flammable vapors.
WHAT TO DO IF YOU SMELL GAS
•Do not try to light any appliance.
•Do not touch any electric switch: do not use any phone in
your building.
•Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
•If you cannot reach your gas supplier, call the fire
department.
Installation and service must be performed by a
qualified installer, service agency or the gas
supplier.
OWNER WARNING
The information contained in this manual is intended
for use by qualified professional installers, service
technicians or gas suppliers. Consult your local expert
for proper installation or service procedures.
IMPORTANT
Consult and follow local Building and Fire Regulations and
other Safety Codes that apply to this installation. Contact
the local gas utility company to authorize and inspect all gas
and flue connections.
A gas appliance that draws combustion air from the equipment
room where it is installed must have a supply of fresh air circulating
around it during burner operation for proper gas combustion and
proper venting.
1. Boilers and water heaters are heat producing appliances.
To avoid damage or injury, do not store materials against
the appliance or the vent-air intake system. Use proper care
to avoid unnecessary contact (especially children) with the
appliance and vent-air intake components.
2. Never cover your appliance, lean anything against it, store
trash or debris near it, stand on it or in any way block the
flow of fresh air to your appliance.
3. UNDER NO CIRCUMSTANCES must flammable
materials such as gasoline or paint thinner be used or stored
in the vicinity of this appliance, vent-air intake system or
any location from which fumes could reach the appliance
or vent-air intake system.
The equipment shall be installed in accordance with those
installation regulations in force in the local 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. In the absence of such requirements, the
installation shall conform to the latest edition of the National Fuel
Gas Code, ANSI Z223.1 and/or CAN/CGA-B149 Installation Code.
Where required by the authority having jurisdiction, the installation
must conform to American Society of Mechanical Engineers Safety
Code for Controls and Safety Devices for Automatically Fired
Boilers, ASME CSD-1. All boilers conform to the latest edition of
the ASME Boiler and Pressure Vessel Code, Section IV. Where
required by the authority having jurisdiction, the installation must
comply with the CSA International, CAN/CGA-B149 and/or local
codes. This appliance meets the safe lighting performance criteria
with the gas manifold and control assembly provided, as specified
in the ANSI standards for gas-fired units, ANSI Z21.13.
CODES
WARNING
Should overheating occur or the gas supply fail to shut off,
DO NOT turn off or disconnect the electrical supply to
the pump. Instead, shut off the gas supply at a location
external to the appliance.
WARNING
To minimize the possibility of serious personal injury, fire or
damage to your appliance, never violate the following safety
rules.
3

4
1. Locate the appliance so that if water connections should
leak, water damage will not occur. When such locations
cannot be avoided, it is recommended that a suitable drain
pan, adequately drained, be installed under the unit. The pan
must not restrict combustion airflow. Under no
circumstances is the manufacturer to be held responsible for
water damage in connection with this unit, or any of its
components.
2. The appliance must be installed so that the ignition
system components are protected from water
(dripping, spraying, etc.) during appliance operation and
service (circulator replacement, control replacement, etc.).
3. Appliances located in a residential garage and in adjacent
spaces that open to the garage and are not part of the living
space of a dwelling unit must be installed so that all burners
and burner ignition devices have a minimum clearance of
not less than 18" (46cm) above the floor. The appliance
must be located or protected so that it is not subject to
physical damage by a moving vehicle.
4. DO NOT install this appliance in any location where
gasoline or flammable vapors are likely to be present.
5. The appliance must be installed on a level floor.
Combustible floor locations may be used. Maintain required
clearances from combustible surfaces.
6. The appliance must not be installed on carpet.
7. The appliance must be installed indoors where it
is protected from exposure to wind, rain and
weather.
8. This appliance may condense the products of
combustion when operating at water temperatures
below 130°F (54.4°C). Ensure that the appliance is
located near an acceptable drain where the
condensate from the heat exchanger and venting
system may be properly collected, neutralized and
disposed.
INSTALLATION PROCEDURE
LOCATION OF UNIT
TABLE - A
Clearances from
Combustible Construction:
Right Side - 0"
Rear - 9" (23 cm) (Minimum 24" (0.61 m) suggested for
service to pump and components)
Left Side - 0"
Front - ALCOVE* (Minimum 24" (0.61 m) suggested for
service)
Flue - 1" (25.4 mm)
Hot Water Pipes - 1" (25.4 mm)
*An ALCOVE is a closet without a door.
RECOMMENDED SERVICE CLEARANCES
FIG. 3 Recommended Service Clearances - Front FIG. 4 Recommended Service Clearances - Rear

5
NOTE
Clearances from combustible construction are noted on the
appliance rating plate.
Maintain minimum specified clearances for adequate operation.
All installations must allow sufficient space for servicing the vent
connections, water pipe connections, integral circulating pump,
bypass piping and other auxiliary equipment, as well as the
appliance. The clearance labels on each appliance note the same
service and combustible clearance requirements as shown in the
clearances from combustion construction table.
Multiple appliances may be installed in a modular boiler or water
heater installation. Multiple appliances may be installed side by
side with no clearance between adjacent appliances because this
appliance is approved for zero clearance from combustible surfac-
es and no service access is required from the sides.
Consult the venting section of the manual for specific installation
instructions for the appropriate type of venting system that you will
be using. Direct Vent and Intelli-Vent venting systems require
installation with Category IV flue pipe, sealed air inlet pipe and air
inlet caps, which must meet the manufacturer’s specifications.
COMBUSTION AND VENTILATION
AIR REQUIREMENTS FOR
APPLIANCES DRAWING AIR FROM
THE EQUIPMENT ROOM
Provisions for combustion and ventilation air must be in accordance
with Section 5.3, Air for Combustion and Ventilation, of the latest
edition of the National Fuel Gas Code, ANSI Z223.1, in Canada,
the latest edition of CAN/CGA Standard B149 Installation Code
for Gas Burning Appliances and Equipment, or applicable
provisions of the local building codes.
The equipment room MUST be provided with properly sized
openings to assure adequate combustion air and proper ventilation
when the unit is installed with a basic Category IV venting system.
FIG. 5 Combustion Air Direct from Outside
1. If air is taken directly from outside the building
with no duct, provide two permanent openings:
a. Combustion air opening, with a minimum free
area of one square inch per 4000 Btu input
(5.5 cm2per kW). This opening must be located
within 12" (30cm) of the bottom of the
enclosure.
b. Ventilation air opening, with a minimum free
area of one square inch per 4000 Btu input
(5.5 cm2per kW). This opening must be located
within 12" (30 cm) of the top of the enclosure.
FIG. 6 Combustion Air Through Ducts
2. If combustion and ventilation air is taken from the outdoors
using a duct to deliver the air to the mechanical room, each of
the two openings should be sized based on a minimum free
area of one square inch per 2000 Btu (11 cm2 per kW) of input.

6
TABLE - B
Minimum Recommended Combustion
AIR SUPPLY TO MECHANICAL ROOM
Btu/hr
Input
1,500,000 375 in2(2419 cm2)
425 in2(2742 cm2)
500 in2(3226 cm2)
500 in2(3226 cm2)
567 in2(3658 cm2)
667 in2(4303 cm2)
1,500 in2(9,677 cm2)
1,700 in2(10,968 cm2)
2,000 in2(12,903 cm2)
1,700,000
2,000,000
Outside Air*
2 - Openings
Outside Air*
1 - Opening
Inside Air
2 - Openings
*Outside air openings shall directly communicate with the outdoors. When combustion air is drawn from the outside through a duct,
the net free area of each of the two openings must have twice (2 times) the free area required for Outside Air/2 Openings. The above
requirements are for the boiler only, additional gas fired appliances in the equipment room will require an increase in the net free area
to supply adequate combustion air for all appliances. Combustion air requirements are based on the latest edition of the National Fuel
Gas Code, ANSI Z223.1, in Canada refer to the latest edition of CAN/CGA B149. Check all local code requirements for combustion
air.
Combustion Air Source
FIG. 7 Combustion Air from Interior Space FIG 8 Combustion Air from Outside - Single Opening
3. If air is taken from another interior space, each of the two
openings specified above should have a net free area of one
square inch for each 1000 Btu (22 cm2per kW) of input,
but not less than 100 square inches (645 cm2).
4. If a single combustion air opening is provided to
bring combustion air in directly from the outdoors,
the opening must be sized based on a minimum
free area of one square inch per 3000 Btu (7 cm2
per kW). This opening must be located within 12"
(30 cm) of the top of the enclosure.
CAUTION
Under no circumstances should the mechanical room ever
be under a negative pressure. Particular care should be taken
where exhaust fans, attic fans, clothes dryers, compressors,
air handling units, etc., may take away air from the unit.

7
All dimensions based on net free area in square inches. Metal
louvers or screens reduce the free area of a combustion air opening
a minimum of approximately 25%. Check with louver
manufacturers for exact net free area of louvers. Where two
openings are provided, one must be within 12" (30 cm) of the
ceiling and one must be within 12" (30 cm) of the floor of the
mechanical room. Each opening must have net free area as
specified in Table - B. Single openings shall commence within 12"
(30 cm) of the ceiling.
The combustion air supply must be completely free of any
flammable vapors that may ignite or chemical fumes which may
be corrosive to the appliance. Common corrosive chemical fumes
which must be avoided are fluorocarbons and other halogenated
compounds, most commonly present as refrigerants or solvents,
such as Freon, trichlorethylene, perchlorethylene, chlorine, etc.
These chemicals, when burned, form acids which quickly attack
the heat exchanger finned tubes, headers, flue collectors, and the
vent system. The result is improper combustion and a non-
warrantable, premature appliance failure.
These chemicals, when burned form acids which quickly attack the
boiler tubes, tube sheets, flue collectors, and the appliance stack.
The result is improper combustion and a non-warrantable, prema-
ture failure of the appliance.
EXHAUST FANS: Any fan or equipment which exhausts air from
the equipment room may deplete the combustion air supply and/or
cause a downdraft in the venting system. Spillage of flue products
from the venting system into an occupied living space can cause a
very hazardous condition that must be immediately corrected. If a
fan is used to supply combustion air to the equipment room, the
installer must make sure that it does not cause drafts that could lead
to nuisance operational problems with the appliance.
A construction air filter is installed on the appliance as shipped.
The filter assembly is installed on the combustion air inlet located
at the rear of the appliance. The filter assembly slips over the air
inlet collar and is secured in place with the clamp provided with
the filter. If limited space is available at the rear of the appliance,
field supplied elbows may be used to mount the filter in the
alternate positions shown in the illustration. This filter is For
Temporary Use Only on an appliance that must be operated for
temporary heat or hot water when a building is under construction.
The filter will provide a temporary means to remove airborne dust,
dirt and particulate matter generated by construction. The filter
prevents airborne particulate contaminants from being drawn into
the burner with the combustion air. The filter can be cleaned
routinely during construction if necessary. Remove the filter to
clean. Wash the filter with water. A flow of water from the inside
to the outside should remove most particle matter. Allow the filter
to dry before reinstalling. Unfiltered combustion air from a
construction site can contain contaminants that will collect in the
burner reducing the firing rate. A burner that becomes clogged with
airborne particulate contaminants must be removed and cleaned to
restore proper operation to the burner. Sustained operation of an
appliance with a clogged burner may result in nuisance operational
problems, bad combustion and non-warrantable component failures.
CONSTRUCTION AIR FILTER
9.000
ELBOW(S)
NOT
PROVIDED
CABINET AIR
INLET OPENING
D
EC
B
EDGE OF SCREEN 2"
MEDIA OVERLAP
FOLD OVERLAP AROUND
EDGE OF SCREEN AS
SHOWN.
PUSH FILTER ONTO AIR
INLET AND FASTEN WITH
CLAMP AS SHOWN.
BAND CLAMP
2"
MODEL ABCD E REAR
2.0 19.750 12.250 4.875 15.000 24.000
1.7
1.5
19.250
18.750
10.750
9.250
4.375
3.875 6.000
7.500
14.000 24.000
14.500 24.000
FRONT
REAR
FIG. 9 Construction Air Filter

8
The construction air filter MUST be removed from the
appliance’s air inlet before the appliance is placed in normal
operation. Once the construction air filter is removed, ensure that
either the equipment room is supplied with combustion air from
properly sized combustion and ventilation air openings or a
combustion air duct from a Direct Vent or Intelli-Vent system is
connected to the appliance. The optional Direct Vent and
Intelli-Vent venting systems have specific requirements for a
special combustion air duct from the outside that is directly
connected to the appliance. See the requirements for this
combustion air duct in the venting section for each specialized
vent system.
CONSTRUCTION AIR FILTER KITS
TABLE - C
Input Construction
Btu/hr Air Filter Kit
1,500,000
________________________
1,700,000
________________________
2,000,000
KIT4000
________________________
KIT4001
________________________
KIT4002
VENTING
Vent System Options
This appliance has three venting system options. They are: (A)
Category IV Venting system with vertical roof top termination or
sidewall termination of the flue and combustion air supplied from
the mechanical room. (B) Direct Vent with a Category IV flue
and a separate combustion air pipe to the outdoors. The Direct
Vent system terminates both the flue and air inlet in the same
pressure zone. The flue outlet and combustion air intake may
terminate on either the sidewall or with a rooftop termination.
(C) Intelli-Vent with a Category IV flue and a separate
combustion air pipe to the outdoors.The Intelli-Vent system
terminates the flue and the combustion air inlet pipe in different
pressure zones. The Intelli-Vent system may terminate the flue on
the roof top and combustion air intake on the sidewall, the flue
on the sidewall and combustion air from the rooftop or the flue
on the sidewall and combustion air from a different sidewall. All
appliances are shipped from the factory equipped for Category
IV venting. The optional Direct Vent and Intelli-Vent venting
systems will require the installation of specific vent kits and
venting materials. The following is a detailed explanation of the
installation requirements for each venting system, components
used and part numbers of vent kits for each model.
General
Vent installations for connection to gas vents or chimneys must be
in accordance with Part 7, “Venting of Equipment,” of the latest
edition of the National Fuel Gas Code, ANSI Z223.1, in Canada,
the latest edition of CAN/CGA Standard B149 Installation Codes
for Gas Burning Appliances and Equipment or applicable
provisions of the local building codes.
Adequate combustion and ventilation air must be supplied to the
equipment room in accordance with the latest edition of the
National Fuel Gas Code, ANSI Z223.1, in Canada, the latest edition
of CAN/CGA Standard B149 Installation Codes for Gas Burning
Appliances and Equipment, or applicable provisions of the local
building codes.
The distance of the vent terminal from adjacent buildings, windows
that open and building openings MUST comply with the latest
edition of the National Fuel Gas Code, ANSI Z223.1, in Canada,
the latest edition of CAN/CGA Standard B149 Installation Code
for Gas Burning Appliances and Equipment.
Vent connection is made directly to the flue outlet opening on the
back of the unit. The connection from the appliance vent to the
stack must be made as direct as possible.
IMPORTANT
Examine the venting system at least once a year. Check all
joints and vent pipe connections for tightness. Also, check
for corrosion or deterioration. Immediately correct any prob-
lems observed in the venting system.
TABLE - D
The Category IV Flue Pipe Sizes
Input Btu/hr Flue Size
1,500,000
________________________
1,700,000
________________________
2,000,000
6"
________________________
7"
_______________________
8"

9
Category IV Venting
A CATEGORY IV POSITIVE
PRESSURE VENTING SYSTEM
FIG. 10 Basic Category IV Venting - Vertical
FIG. 11 Basic Category IV Venting - Horizontal
A Category IV venting system for the flue products is required on
all models of this appliance. A Category IV venting system
operates with a positive pressure in the vent. This positive pressure
is generated by the internal combustion air blower which operates
the combustion process and also exhausts the flue products from
the building. The Category IV flue from this appliance can NOT
be combined with the vent from any other appliance. The Category
IV flues from multiple appliances can NOT be combined into a
common vent. The Category IV flue from this appliance must be
a dedicated stack. The flue from this Category IV appliance must
have all vent joints and seams sealed gas-tight. A Category IV
vent system has specific vent material and installation requirements.
The flue products in the vent system may be cooled below their
dew point and form condensate in the flue. The
materials used for a Category IV vent must be resistant to any
corrosive damage from flue gas condensate. The flue from a
Category IV vent system must have a condensate drain with
provisions to properly collect and dispose of any condensate that
may occur in the venting system.
Category IV Flue Pipe Materials
Select venting material from the following specified vent
distributors:
Heat-Fab Inc. Saf-T CI Vent with AL29-4C stainless steel
(Call 1-800-772-0739 for nearest distributor)
Protech Systems Inc. Fas N Seal Vent with AL29-4C stainless
steel (Call 1-800-766-3473 for nearest distributor)
Z-Flex Z-Vent with AL29-4C stainless steel
(Call 1-800-654-5600 for nearest distributor)
Or other listed Category IV vent systems suitable for a condensing,
positive pressure gas fired appliance.
Venting Guidelines for a Category IV Vent
The connection from the appliance vent to the stack or vent
termination outside the building MUST be made with listed
Category IV vent system and must be direct as possible with no
reduction in diameter. The Category IV vent and accessories, such
as firestop spacers, thimbles, caps, etc., MUST be installed in
accordance with the vent manufacturers instructions. The vent
connector and firestop must provide correct spacing to combustible
surfaces and seal to the vent connector on the upper and lower sides
of each floor or ceiling through which the vent connector passes.
In a typical installation, each appliance must have a dedicated
Category IV flue with no other appliance interconnected to any
part of the dedicated flue. Each appliance MUST connect to the
dedicated flue stack using a properly sealed vent adapter provided
by the vent manufacturer. The flues from multiple Intelli-Fin
appliances may only be combined when using an engineered vent
system incorporating an induced draft fan to ensure that flue
products will be properly exhausted from the building at all times.
Failure to use a properly sized induced draft fan on a combined vent
installation may result in a hazardous condition where flue gases
spill into an occupied living space. Consult the induced draft fan
manufacturer to size the induced draft fan and to determine the
diameter of the common vent pipe required for a combined vent
installation.

10
Any vent materials specified must be listed by a nationally
recognized test agency for use as a Category IV vent material.
The venting system must be planned so as to avoid possible
contact with concealed plumbing or electrical wiring inside walls,
floors or ceilings. Locate the appliance as close as possible to a
chimney or gas vent.
There shall be no reductions in vent diameter.
Horizontal portions of the venting system shall be supported to
prevent sagging. Horizontal runs should slope upwards not less
than 1/4 inch per foot (21 mm/m) from the drain tee installed in
the flue to the vertical portion of the flue or to the vent terminal
on sidewall venting installations. This ensures proper removal of
any condensate that may form in the flue. Follow the installation
instructions from the vent material manufacturer.
Do not use an existing chimney as a raceway if another appliance
or fireplace is vented through the chimney. The weight of the
venting system must not rest on the unit. Adequate support of the
venting system must be provided in compliance with local codes
and other applicable codes. All connections should be secured
and sealed per the vent manufacturers specifications.
Vent connectors serving appliances vented by natural draft shall
not be connected to any portion of the Category IV positive
pressure vent system used by this appliance. Connection of a
negative draft flue into the positive pressure stack from this
appliance may cause flue products to be discharged into an
occupied living space causing serious health injury.
When a Category IV vent system is disconnected for any reason,
the flue must be reassembled and resealed according to the vent
manufacturer’s instructions.
The installed length of the Category IV flue from the appliance
to the point of termination, outside of the building, must not
exceed a maximum of 100 equivalent feet (30.5 m) in length.
Subtract 5 feet (1.5 m) of equivalent length for each 90° elbow
installed in the vent. Subtract 2 1/2 feet (0.7 m) of equivalent
length for each 45° elbow installed in the vent.
The flue may terminate either vertically at the roof top or
horizontally on a sidewall. See the information about the specific
vent termination location for recommended location and
clearances.
General Category IV Vent Termination Clearances
The vent cap should have a minimum clearance of 4 feet (1.2 m)
horizontally from and in no case above or below, unless a 4 foot
(1.2 m) horizontal distance is maintained from electric meters,
gas meters, regulators and relief equipment.
The venting system shall terminate at least 3 feet (0.9 m) above
any forced air inlet within 10 feet (3.05 m).
The venting system shall terminate at least 4 feet (1.2 m) below,
4 feet (1.2 m) horizontally from, or 1 foot (30 cm) above any
door, window or gravity air inlet into any building.
Do not terminate the vent in a window well, stairwell, alcove,
courtyard or other recessed area. The vent cannot terminate
below grade. The bottom of the vent terminal shall be located at
least 12 inches (30 cm) above grade and above normal snow levels.
To avoid a blocked flue condition, keep the vent cap clear of snow,
ice, leaves, debris, etc.
Flue gases from this appliance may contain large amounts of water
vapor that will form a white plume in winter. Plume could obstruct
a window view.
Flue gas condensate can freeze on exterior surfaces or on the vent
cap. Frozen condensate on the vent cap can result in a blocked flue
condition. Flue gas condensate can cause discoloration of exterior
building surfaces. Adjacent brick or masonry surfaces should be
protected with a rust resistant sheet metal plate.
The manufacturer shall NOT be held liable for any personal injury
or property damage due to ice formation or the dislodging of ice
from the vent system or the vent termination.
Drain Tee Installation
WIRE TIE 4" Ø
CIRCULAR TRAP
TO SUITABLE DRAIN
FIG. 12 Drain Tee
A drain tee MUST be installed in the Category IV vent pipe to
collect and dispose of any condensate that may occur in the vent
system. The drain tee should be installed at the point where the
flue turns vertical for a roof top termination or as one of the first
fittings in a horizontal flue that will terminate on a sidewall. Ensure
that horizontal portions of the vent are properly sloped to allow
condensate to be evacuated at the drain tee. See the typical vent
installation drawings. Plastic drain tubing, sized per the vent
manufacturer’s instructions, shall be provided as a drain line from

11
the tee. The drain tubing must have a trap provided by a 4"
(10.2 cm)-diameter circular trap loop in the drain tubing. Prime
the trap loop by pouring a small quantity of water into the drain
hose before assembly to the vent. Secure the trap loop in position
with nylon wire ties. Use caution not to collapse or restrict the
condensate drain line with the nylon wire ties. The condensate
drain must be routed to the condensate neutralization system or a
suitable drain for disposal of condensate that may occur in the
Category IV vent system. Refer to the condensate drain
installation instructions as supplied by the manufacturer of the vent
material. Ensure that the drain from the condensate tee is not
exposed to freezing temperatures. See “Freeze Protection” for
more information.
MASONRY CHIMNEY
INSTALLATIONS
A standard masonry chimney must NOT be used to vent the
products of combustion from the flue of a Category IV,
positive pressure appliance. If a masonry chimney is to be used,
the chimney MUST use a sealed, metallic, corrosion
resistant liner system to vent flue products from this high
efficiency appliance. Sealed, metallic, corrosion resistant liner
systems (single wall, double-wall, or flexible or rigid metallic
liners) must be rated for use with a high efficiency Category IV,
positive pressure vent system. Corrosion resistant chimney liner
systems are typically made from a high grade of corrosion resistant
stainless steel such as AL 29-4C. The corrosion resistant liner must
be properly sized and fully sealed throughout the entire length if
the flue is contained within the masonry chimney. Both the top and
the bottom of the masonry chimney must be capped and sealed to
provide a dead air space around the sealed corrosion resistant
metallic liner. Consult with local code officials to determine code
requirements or the advisability of using a masonry chimney
with a sealed corrosion resistant liner system.
CAUTION
Venting of a high efficiency Category IV appliance into a
masonry chimney without a sealed stainless steel liner can
result in operational and safety problems. Any breaks, leaks
or damage to the masonry flue/tile will allow spillage of the
positive pressure flue products from the chimney. These
flue products can easily escape into an occupied living
space causing a health hazard. If there is any doubt about
the condition of a masonry chimney, or its acceptability for
use after insertion of a corrosion resistant liner system,
consult with local code officials.
VERTICAL VENTING
TERMINATIONS
Follow all General Category IV Vent Termination Clearances.
RIDGE
CHIMNEY
3' MIN
2' MIN
10' OR LESS
FIG. 13 Vent Termination from Peaked Roof - 10 Feet or Less
from Ridge
RIDGE
CHIMNEY
3' MIN
2' MIN
MORE THAN 10'
10'
FIG. 14 Vent Termination from Peaked Roof - 10 Feet or
More from Ridge
The vent terminal should be vertical and exhaust outside the build-
ing at least 2 feet (0.61 m) above the highest point of the roof within
a 10 foot (3.05 m) radius of the termination.
The vertical termination must be a minimum of 3 feet (0.91 m)
above the point of exit.

12
CHIMNEY
3' MIN
2' MIN
10' OR LESS
CHIMNEY
2' MIN
WALL OR
PARAPET
FIG. 15 Vent Termination from Flat Roof - 10 Feet or
Less from Parapet Wall
3' MIN
10' OR MORE
CHIMNEY
WALL OR
PARAPET
NOTE: NO HEIGHT
ABOVE PARAPET
REQUIRED WHEN
DISTANCE FOR
WALLS OR PARAPETS
IS MORE THAN 10'>
FIG. 16 Vent Termination from Flat Roof - 10 Feet or
More from Parapet Wall
A vertical termination less than 10 feet (3.05 m) from a parapet
wall must be a minimum of 2 feet (0.61 m) higher than the
parapet wall.
SIDEWALL VENTING
TERMINATIONS
This venting system uses the appliance’s internal combustion air
blower to force the flue products out of a horizontally-terminated
flue. This blower generates a positive pressure in the flue.
Combustion air is drawn from the equipment room (see
Combustion and Ventilation Air Requirements) unless the
appliance is equipped with an optional Direct Vent or Intelli-Vent
System.
FIG. 17 Sidewall Venting Installation
The connection from the appliance flue outlet to the sidewall vent
cap MUST be made with listed type Category IV vent materials
and accessories. The installer must supply suitable vent pipe
material. The sidewall vent cap is available from the appliance
manufacturer as a vent kit.
FIG. 18 Sidewall Vent Cap
TABLE - E
Sidewall Vent Cap Kits
Sidewall Vent
Input Btu/hr Flue Size Cap Kit
1,500,000
________________
1,700,000
________________
2,000,000
6"
_____________
7"
_____________
8"
SVK3026
_________________
SVK3027
_________________
SVK3028
The sidewall vent cap kit includes the wall penetration assembly
and the discharge screen assembly. All required Category IV vent
pipe and fittings must be purchased locally.

13
The installed sidewall vent cap assembly may be painted to match
the exterior color. The opening through the wall for installation of
the sidewall vent cap must provide an air space clearance of
2 inches (5.1 cm) around the flue pipe. The diameter of the opening
for installation of the sidewall cap will be 4 inches (10.2 cm) larger
(minimum) than the nominal diameter of the installed vent pipe to
the sidewall cap.
The sidewall cap is installed from the outside and mounted to the
wall with four screws or wall anchors. Seal under the screw heads
with caulking. Install the screen assembly using the stainless steel
screws provided in the kit. Install the Category IV vent pipe from
the appliance to the vent cap. The installed vent pipe must protrude
at least 2 inches (5.1 cm) into the screen area beyond the thimble
portion of the sidewall cap assembly. See detailed instructions
packed with the sidewall vent kit.
Follow all requirements in the General Category IV Venting
sections for venting flue products to the outdoors. See the
Combustion and Ventilation Air Requirements section to ensure
that adequate combustion and ventilation air is supplied to the
equipment room. All other general installation requirements must
be followed.
LOCATION OF A SIDEWALL
VENT TERMINATION
Follow all General Category IV Vent Termination Clearances.
3' MIN.
4' MIN.
10' MIN.
HORIZONTALLY
FIG. 19 Sidewall Venting Installation with Clearances from
Vent Cap
The vent cap shall terminate at least 3 feet (0.91 m) above any
forced air inlet within 10 feet (3.05 m) horizontally.
The vent cap MUST NOT terminate below a forced air intake at
any distance.
The vent shall terminate at least 4 feet (1.22 m) below, 4 feet
(1.22 m) horizontally from or 1 foot (0.30 m) above and 2 feet (0.60
m) horizontally from any door, window or gravity air inlet to the
building.
The sidewall vent termination must be at least 8 feet (2.4 m)
horizontally from any combustion air intake located above the
sidewall termination cap.
Do not terminate the vent in a window well, stairwell, alcove,
courtyard or other recessed area. The vent cannot terminate below
grade.
The vent shall not terminate directly above a public walkway due
to the normal formation of water vapor in the combustion process.
Horizontal terminations must not be located over areas of
pedestrian or vehicular traffic.
The vent system shall terminate at least 1 foot (0.30 m) above
grade, above normal snow levels and at least 7 feet (2.13 m) above
grade when located adjacent to public walkways.
The vent terminal shall not be installed closer than 3 feet
(0.91 m) from an inside corner of an L-shaped structure.
The vent cap should have a minimum clearance of 4 feet
(1.22 m) horizontally from and in no case above or below, unless
a 4-foot (1.22 m) horizontal distance is maintained from electric
meters, gas meters, regulators and relief equipment.
Flue gas condensate can freeze on exterior walls or on the vent
cap. Frozen condensate on the vent cap can result in a blocked
flue condition. Some discoloration to exterior building surfaces
can be expected. Adjacent brick or masonry surfaces should be
protected with a rust resistant sheet metal plate.
The sidewall vent system must use the sidewall vent cap kit
provided by the appliance manufacturer for installation on a
sidewall termination.
The sidewall vent cap MUST be purchased as a kit from the
appliance manufacturer to ensure proper operation. Locally
purchased or fabricated sidewall vent caps should not be used.
DIRECT VENT AND
INTELLI-VENT SYSTEMS
Direct Vent and Intelli-Vent Systems are installed with a Category
IV flue and a separate combustion air pipe to the outdoors. The
Direct Vent System terminates both the flue and combustion air
inlet in the same pressure zone. The Intelli-Vent System terminates
the flue and combustion air inlet in different pressure zones. The
flue outlet and combustion air intake may terminate with either a
sidewall or a rooftop termination.
Follow all requirements in the General Category IV Venting
sections for proper installation and venting of flue products
vertically or horizontally to the outdoors. All other general
installation requirements must be followed.
The Direct Vent and Intelli-Vent Systems require the installation of
an additional pipe to supply combustion air from outdoors directly
to the appliance.

14
In cold climates, the use of type “B” double wall vent pipe or an
insulated single wall pipe for combustion air is recommended to
help prevent moisture in the cool incoming air from condensing
and leaking from the inlet pipe.
Termination point for the flue products must follow the clearance
requirements in the Vertical or Horizontal Vent Termination
sections of the Category IV Venting.
CAUTION
Appliances that are shut down or will not operate may
experience freezing due to convective airflow in the air
inlet pipe connected to the appliance.
TABLE - F
Direct Vent and Intelli-Vent Flue
and Air Inlet Pipe Sizes
Air Inlet
Input Btu/hr Flue Size Pipe Size
1,500,000
________________
1,700,000
________________
2,000,000
6"
______________
7"
_____________
8"
6"
________________
7"*
________________
8"
*Piping from the appliance to the air inlet cap may be either 7"
or 8". An 8" diameter sidewall air inlet cap is provided in the
vent kit.
Length of Air Inlet Pipe
The maximum total length of the sidewall or vertical roof top
combustion air inlet pipe as installed from the appliance to the air
inlet cap must not exceed 100 equivalent feet (30.5 m) in length.
Subtract 5 feet (1.52 m) of equivalent length for each 90° elbow
installed in the air inlet pipe system. Subtract 2 1/2 feet (0.7 m)
of equivalent length for each 45° elbow installed in the air inlet
pipe system.
Do not exceed limits for the combustion air inlet piping lengths.
Air Inlet Pipe Materials
The air inlet pipe(s) must be sealed. Choose acceptable
combustion air inlet pipe materials from those specified in this
section.
Select air inlet pipe material from the following specified
materials:
• PVC, CPVC or ABS (6", 7"or 8" I.D.)*.
• Dryer Vent or Sealed Flexible Duct (not recommended
for roof top air inlet).
• Galvanized steel vent pipe with joints and seams
sealed as specified below.
• Type “B” double wall vent with joints and seams
sealed as specified below.
* Plastic pipe may require an adapter (not provided) to transition
between the air inlet connection on the appliance and the plastic air
inlet pipe.
WARNING
Using vent or air intake materials other than those specified,
failure to properly seal all seams and joints or failure to
follow vent pipe manufacturer’s instructions can result in
personal injury, death or property damage. Mixing of
venting materials will void the warranty and certification
of the appliance.
Sealing of Type “B” double wall vent material or galvanized vent
pipe material used for air inlet pipe on a sidewall or vertical roof top
Combustion Air Supply System.
a. Seal all joints and seams of the air inlet pipe
using either Aluminum Foil Duct Tape meeting
UL Standard 723 or 181A-P or a high quality
UL Listed silicon sealant such as those
manufactured by Dow Corning or General
Electric.
b. Do not install seams of vent pipe on the
bottom of horizontal runs.
c. Secure all joints with a minimum of three sheet
metal screws or pop rivets. Apply aluminum
foil duct tape or silicone sealant to all screws
or rivets installed in the vent pipe.
d. Ensure that the air inlet pipes are properly
supported.
The PVC, CPVC or ABS air inlet pipe should be cleaned and sealed
with the pipe manufacturers recommended solvents and standard
commercial pipe cement for the material used. The PVC, CPVC,
ABS, Dryer Vent or Flex Duct air inlet pipe should use a silicone
NOTE:
The use of double wall vent or insulated material for the
combustion air inlet pipe is recommended in cold climates
to prevent the condensation of airborne moisture in the
incoming combustion air.

15
sealant to ensure a proper seal at the appliance connection and the
air inlet cap connection. Dryer vent or flex duct should use a screw
type clamp to seal the vent to the appliance air inlet and the air inlet
cap. Proper sealing of the air inlet pipe ensures that combustion
air will be free of contaminants and supplied in proper volume.
When a sidewall or vertical roof top combustion air supply
system is disconnected for any reason, the air inlet pipe must be
resealed to ensure that combustion air will be free of
contaminants and supplied in proper volume.
DANGER 
Failure to properly seal all joints and seams as required in
the air inlet piping may result in flue gas recirculation,
spillage of flue products and carbon monoxide emissions
causing severe personal injury or death.
Combined Combustion Air Inlet Points
The air inlet pipes from multiple appliances can be combined to a
single common connection if the common air inlet pipe has a cross
sectional area equal to or larger than the total area of all air inlet
pipes connected to the common air inlet pipe. {Example: two 8"
(20.3 cm) air inlet pipes [50.3 in2(324.5 cm2) area each] have a
total area of 100.6 in2(645.2 cm2) requires a 12" (30.5 cm) [113.1
in2(729.7 cm2] common air inlet pipe.} The air inlet point for mul-
tiple boiler air inlets must be provided with an exterior opening
which has a free area equal to or greater than the total area of all air
inlet pipes connected to the common air inlet. This exterior opening
for combustion air must connect directly to the outdoors. The total
length of the combined air inlet pipe must not exceed a maximum
of 100 (30.5 m) equivalent feet. You must deduct the restriction in
area provided by any screens, grills or louvers installed in the
common air inlet point. These are common on the sidewall air inlet
openings and some rooftop terminations. Screens, grills or louvers
installed in the common air inlet can reduce the free area of the
opening from 25% to 75% based on the materials used.
VERTICAL DIRECT VENT SYSTEMS
A Vertical Direct Vent System is installed with a Category IV flue
and a separate combustion air pipe to the outdoors. The Direct Vent
system terminates both the flue and air inlet in the same pressure
zone. The flue outlet and combustion air intake must both terminate
on the rooftop.
Follow all requirements in the General Category IV Venting
sections for proper installation and of venting flue products
vertically to the outdoors. All other general installation
requirements must be followed.
The Direct Vent system requires the installation of an additional
pipe to supply combustion air from outdoors directly to the
appliance. The air inlet pipe must use one of the specified
materials.
The maximum installed length of the air inlet pipe from the
appliance to the air inlet cap is 100 equivalent feet (30.48 m) in
length. The maximum installed length of the flue pipe from the
appliance to the termination cap is 100 equivalent feet
(30.48 m) in length. Subtract 5 feet (1.52 m) of equivalent length
for each 90° elbow installed in either the flue pipe or the air inlet
pipe.
Termination point for the flue products must follow the clearance
requirements in the Vertical Vent Termination sections of the
Category IV Venting.
FIG. 20 Vertical Direct Vent Installation with Rooftop
Combustion Air Inlet
3'
12"

16
VERTICAL COMBUSTION AIR INLET
FIG. 21 Air Inlet Cap for Rooftop Termination
The air inlet cap for the vertical roof top air inlet is assembled
from components purchased locally. The air inlet cap consist of
two 90° elbows installed at the point of termination for the air
inlet pipe. The first 90° elbow is installed on the rooftop at the
highest vertical point of the air inlet pipe and turned horizontal,
the second 90° elbow is installed on the horizontal outlet of the
first elbow and turned down. A 90° elbow and a 90° street elbow
may be used to make this assembly. If a straight piece of pipe is
used between the two elbows, it should not exceed 6" (150 mm)
in length. The termination elbow on the air inlet must be located
a minimum of 12" (0.30 m) above the roof or above normal levels
of snow accumulation.
The point of termination for the combustion air inlet cap MUST
be at least 3 feet (0.91 m) below the point of flue gas termination
(vent cap) if it is located within a 10 foot (3.05 m) radius of the
flue outlet. Use care to ensure that the 90° elbow assembly is
properly installed on the air inlet pipe.
The combustion air inlet cap must not be installed closer than
10 feet (3.05 m) from an inside corner of an L-shaped structure.
The termination point of the combustion air inlet cap must be
installed at least one foot (0.30 m) above the rooftop and above
normal snow levels.
The combustion air cap assembly used MUST adequately protect
the combustion air inlet from wind and weather.
The combustion air cap and flue gas outlet MUST be located on
the same roof top surface and in the same pressure zone.
Combustion air supplied from outdoors must be free of
contaminants (see Combustion and Ventilation Air). To prevent
recirculation of flue products in to the combustion air inlet, follow
all instructions in this section.
Incorrect installation and/or location of the air inlet cap can allow
the discharge of flue products to be drawn into the combustion
process on the heater. This can result in incomplete combustion
and potentially hazardous levels of carbon monoxide in the flue
products. This will cause operational problems with the heater and
possible spillage of flue products that can cause personal injury,
death or property damage.
Multiple Vertical Direct Vent Installations
FIG. 22 Multiple Vertical Direct Vent Installations
The combustion air inlet caps for multiple appliance installations
must maintain the minimum 3 foot (0.91 m) clearance below the
closest vertical flue outlet if within 10 feet (3.05 m). Multiple flue
outlet caps may be installed side by side and multiple air inlet caps
may be installed side by side but the air inlet must always be at
least 3 feet (0.91 m) below the closest flue outlet if the outlet is
within 10 feet (3.05 m). All clearance and installation requirements
in this section and the applicable portions of the general Category
IV venting section must be maintained on multiple appliance
installations.
For venting flue products horizontally to the outdoors, follow all
requirements in the installation instructions for sidewall venting.
Termination point for the flue products must follow the clearance
requirements in the Sidewall Vent Termination section of Category
IV Venting.
A Horizontal Direct Vent System is installed with a Category IV flue
and a separate combustion air pipe to the outdoors. The Direct Vent
system terminates both the flue and air inlet in the same pressure
zone. The flue outlet and combustion air intake must both terminate
on the same sidewall.
Follow all requirements in the General Category IV Venting
sections for proper installation and of venting flue products to the
outdoors with a sidewall termination. All other general
installation requirements must be followed.
HORIZONTAL DIRECT VENT

17
The Direct Vent system requires the installation of an additional
pipe to supply combustion air from outdoors directly to the
appliance. The air inlet pipe must use one of the specified
materials.
The maximum installed length of the air inlet pipe from the
appliance to the air inlet cap is 100 equivalent feet (30.48 m) in
length. The maximum installed length of the flue pipe from the
appliance to the termination cap is 100 equivalent feet
(30.48 m) in length. Subtract 5 feet (1.52 m) of equivalent
length for each 90° elbow installed in either the flue pipe or the
air inlet pipe. Subtract 2 1/2 feet (0.7 m) of equivalent length for
each 45° elbow installed in either the flue or the air inlet pipe.
Termination point for the flue products must follow the clearance
requirements in the Sidewall Venting Termination sections of the
Category IV Venting.
FIG. 23 Horizontal Direct Vent Installations with Sidewall
Combustion Air Inlet
SIDEWALL COMBUSTION
AIR INLET
Horizontal Direct Vent systems installed with sidewall terminations
for both combustion air and flue products must purchase the
termination caps from the appliance manufacturer. The sidewall
air inlet cap and sidewall vent cap for flue products are available as
a vent kit.
FIG. 24 Sidewall Vent Cap
The part numbers for the required sidewall air inlet cap kit are listed
by unit size. The manufacturer, in accordance with CSA
requirements, must furnish the sidewall air inlet cap. Each kit
includes the special combustion air inlet cap for installation on an
exterior sidewall. The sidewall air inlet cap supplied in the kit is
sized to provide combustion air for a single appliance only.
TABLE - G
Flue Air Inlet Sidewall Air
Input Cap Cap Inlet & Flue
Btu/hr Size Size Cap Kit
1,500,000
___________
1,700,000
___________
2,000,000
6"
__________
7"
__________
8"
6"
__________
8"*
__________
8"
HDK3018
______________
HDK3019
______________
HDK3020
*Piping from the appliance to the air inlet cap may be either 7" or
8" connecting to an 8" sidewall cap provided in the kit.
Location of a Sidewall Air Inlet Cap
Incorrect installation and/or location of the air inlet cap can allow
the discharge of flue products to be drawn into the combustion
process on the heater. This can result in incomplete combustion and
potentially hazardous levels of carbon monoxide in the flue
products. This will cause operational problems with the heater and
possible spillage of flue products that can cause personal injury,
death or property damage.
The termination point of the sidewall air inlet must be installed a
minimum of 12 inches (0.30 m) above ground level and above
normal levels of snow accumulation.
The point of termination for the sidewall combustion air inlet cap
MUST be located a minimum of 3 feet (0.92 m) horizontally and
12 inches (0.30 m) below the point of flue gas termination (vent
cap) if it is located within a 10 foot (3.05 m) radius of the flue
outlet.

18
The sidewall combustion air inlet cap MUST NOT be installed
above the sidewall flue outlet if it is located within a 10 foot
(3.05 m) radius of the flue outlet.
The sidewall combustion air inlet cap must not be installed closer
than 10 feet (3.05 m) from an inside corner of an
L-shaped structure.
The sidewall combustion air cap assembly used MUST
adequately protect the combustion air inlet from wind and
weather.
The sidewall combustion air inlet cap and flue gas outlet MUST
be located on the same sidewall surface and in the same pressure
zone.
Combustion air supplied from outdoors must be free of
contaminants (see Combustion and Ventilation Air). To prevent
recirculation of flue products into the combustion air inlet, follow
all instructions in this section.
Multiple Horizontal Direct Vent Installations
3' HORIZONTALLY
1' BELOW FLUE
FLUE OUTLETS
AIR INLET CAP
FIG. 26 Multiple Horizontal Direct Vent Caps Installed on a
Sidewall
INTELLI-VENT SYSTEMS
The combustion air inlet caps for multiple appliance installations
must maintain the same minimum clearance from the closest vent
cap installed within a 10 foot (3.05 m) radius of the point of flue gas
termination as specified in single appliance installations. Multiple
flue outlet caps may be installed side by side and multiple air inlet
caps may be installed side by side but the minimum clearance of
3 feet (0.91 m) horizontal radius and 12 inches (0.30 m) below the
closest flue outlet to the air inlet cap must be maintained. All
clearance and installation requirements in this section and the
applicable portions of the general Category IV venting section
must be maintained on multiple appliance installations.
An Intelli-Vent system is a Category IV flue installed with a
separate combustion air pipe to the outdoors. The
Intelli-Vent system terminates the flue and the combustion air inlet
pipe in different pressure zones. The Intelli-Vent system may
terminate the flue and combustion air in any one of three
configurations.
These are:
(1) The flue on the roof top and combustion air intake
on the sidewall;
(2) The flue on the sidewall and combustion air from
the rooftop;
(3) The flue on the sidewall and the combustion air on
a sidewall other than the sidewall where the flue
is located.
All appliances are shipped from the factory equipped for Category
IV venting system. The optional Intelli-Vent systems require the
installation of specific venting materials that are purchased locally.
Sidewall termination caps for flue products and combustion air
must be purchased from the manufacturer. The sidewall caps for
combustion air and flue products are available as vent kits. The
following is a detailed explanation of the installation requirements
for each venting system, components used and part numbers of
vent kits for each model.
Follow all requirements in the General Category IV Venting
sections for proper installation and of venting flue products to the
outdoors with either a rooftop or a sidewall termination. All other
general installation requirements must be followed.
The Intelli-Vent System requires the installation of an additional
pipe to supply combustion air from outdoors directly to the
appliance. The air inlet pipe must use one of the specified
materials.
FIG. 25 Air Inlet Cap for Sidewall Termination

19
Combined Air Inlet Points
The air inlet pipes from multiple appliances installed with an
Intelli-Vent system can be combined to a single common connection
based on the cross sectional area of the common pipe as defined in the
Direct Vent basic information section.
Maximum Length of an Intelli-Vent System
The maximum installed length of the air inlet pipe from the
appliance to the air inlet cap is 100 equivalent feet (30.5 m) in
length. The maximum installed length of the flue pipe from the
appliance to the termination cap is 100 equivalent feet (30.5 m)
in length. Subtract 5 feet (1.52 m) of equivalent length for each
90° elbow installed in either the flue pipe or the air inlet pipe.
Subtract 2 1/2 feet (0.7 m) of equivalent length for each 45° elbow
installed in either the flue pipe or the air inlet pipe.
VERTICAL INTELLI-VENT WITH
SIDEWALL COMBUSTION AIR
FIG. 27 Vertical Intelli-Vent Installation - Sidewall Combustion
Air Inlet
Intelli-Vent systems are installed with a Category IV flue and a
separate combustion air pipe to the outdoors. The Vertical
Intelli-Vent system terminates the flue at the rooftop and air inlet
at the sidewall. The flue outlet and combustion air intake terminates
in different pressure zones.
Follow all requirements in the General Category IV Venting
sections for proper installation and venting of flue products
vertically to the outdoors. All other general installation
requirements must be followed.
The Intelli-Vent system requires the installation of an additional
pipe to supply combustion air from outdoors directly to the
appliance.
Termination point for the flue products must follow the clearance
requirements in the Vertical Vent Termination section of the
Category IV Venting.
CAUTION
Appliances that are shut down or will not operate may
experience freezing due to convective airflow in the air inlet
pipe connected to the appliance.
SIDEWALL COMBUSTION
AIR INLET
FIG. 28 Air Inlet Cap for Sidewall Termination
The air inlet cap for the sidewall air inlet must be purchased from
the appliance manufacturer.
The part numbers for the required sidewall air inlet cap kit are listed
by unit size. The appliance manufacturer, in accordance with CSA
requirements, must furnish the sidewall air inlet cap. Each kit
includes the special combustion air inlet cap for installation on an
exterior sidewall.
TABLE - H
Air Inlet Sidewall
Input Flue Pipe Air Inlet
Btu/hr Size Size Cap Kit
1,500,000
___________
1,700,000
___________
2,000,000
6"
___________
7"
___________
8"
6"
___________
7"*
___________
8"
SAK3000
___________
SAK3001
___________
SAK3002
*Piping from the appliance to the air inlet cap may be either 7" or
8" connecting to an 8" sidewall cap provided in the kit.

20
Location of a Sidewall Air Inlet Cap
Installation, location and clearance requirements for the sidewall
air inlet cap in an Intelli-Vent application are the same as the
installation, location and clearance requirements for the sidewall
air inlet cap in the Horizontal Direct Vent section of the venting
instructions.
The sidewall combustion air inlet cap and the rooftop flue gas
outlet are located in different pressure zones in an Intelli-Vent
system.
Combustion air supplied from outdoors must be free of
contaminants (see Combustion and Ventilation Air). To prevent
recirculation of flue products in to the combustion air inlet,
follow all instructions in this section.
Incorrect installation and/or location of the air inlet cap can allow
the discharge of flue products to be drawn into the combustion
process on the heater. This can result in incomplete combustion
and potentially hazardous levels of carbon monoxide in the flue
products. This will cause operational problems with the heater
and possible spillage of flue products that can cause personal
injury, death or property damage.
HORIZONTAL INTELLI-VENT WITH
VERTICAL COMBUSTION AIR
Intelli-Vent systems are installed with a Category IV flue and a
separate combustion air pipe to the outdoors. The Horizontal
Intelli-Vent system terminates the flue at the sidewall and air inlet
at the rooftop. The flue outlet and combustion air intake
terminate in different pressure zones.
12" MIN.
FIG. 29 Horizontal Intelli-Vent Installation - Rooftop
Combustion Air Inlet
Follow all requirements in the General Category IV Venting
sections for proper installation and of venting flue products
horizontally to the outdoors. All other general installation
requirements must be followed.
The Intelli-Vent system requires the installation of an additional
pipe to supply combustion air from outdoors directly to the
appliance.
In cold climates, the use of type “B” double wall vent pipe or an
insulated single wall pipe is recommended to prevent moisture in
the cool incoming air from condensing and leaking from the inlet
pipe.
Termination point for the flue products must follow the clearance
requirements in the Horizontal Sidewall Vent Termination section
of the Category IV Venting.
CAUTION
Appliances that are shut down or will not operate may
experience freezing due to convective airflow in the air inlet
pipe connected to the appliance.
The flue and air inlet duct sizes for a Horizontal
Intelli-Vent Installation with Rooftop Combustion Air Inlet are
listed by unit size. The sidewall vent cap must be purchased from
the appliance manufacturer as a vent kit.
TABLE - I
Air Inlet Sidewall
Input Flue Pipe Vent
Btu/hr Size Size Cap Kit
1,500,000
___________
1,700,000
___________
2,000,000
6"
___________
7"
___________
8"
6"
___________
7"*
___________
8"
SVK3026
____________
SVK3027
____________
SVK3028
*Piping from the appliance to the air inlet cap may be either 7" or
8" connecting to an 8" sidewall cap provided in the kit.