This manual must only be used by
a qualified heating installer / service
technician. Read all instructions,
including this manual and the
Knight Boiler Service Manual,
before installing. Perform steps in
the order given. Failure to comply
could result in severe personal
injury, death, or substantial property
damage.
Revision Notes .................................................. Back Cover
Hazard definitions
The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels or
to important information concerning the life of the product.
DANGER
WARNING
CAUTION
CAUTION
NOTICE
2
DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious
injury.
WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious
injury.
CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate
injury.
CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not
avoided, may result in property damage.
NOTICE indicates special instructions on installation, operation, or maintenance that are important but not
related to personal injury or property damage.
Please read before proceeding
Installation & Operation Manual
WARNING
NOTICE
WARNING
WARNING
Installer – Read all instructions, including
this manual and the Knight Boiler Service
Manual, before installing. Perform steps
in the order given.
User – This manual is for use only
by a qualified heating installer/
service technician. Refer to the User’s
Information Manual for your reference.
Have this boiler serviced/inspected by
a qualified service technician, at least
annually.
Failure to comply with the above could
result in severe personal injury, death or
substantial property damage.
When calling or writing about the boiler
– Please have the boiler model and serial
number from the boiler rating plate.
Consider piping and installation when
determining boiler location.
Any claims for damage or shortage in
shipment must be filed immediately
against the transportation company by
the consignee.
Factory warranty (shipped with unit) does
not apply to units improperly installed or
improperly operated.
Failure to adhere to the guidelines on this
page can result in severe personal injury,
death, or substantial property damage.
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.
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 near by 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.
When servicing boiler –
• To avoid electric shock, disconnect electrical supply
before performing maintenance.
• To avoid severe burns, allow boiler to cool before
performing maintenance.
Boiler operation –
• Do not block flow of combustion or ventilation air to
the boiler.
• Should overheating occur or gas supply fail to shut off,
do not turn off or disconnect electrical supply to
circulator. Instead, shut off the gas supply at a location
external to the appliance.
• Do not use this boiler 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.
Boiler water –
• Thoroughly flush the system (without boiler
connected) to remove sediment. The high-efficiency
heat exchanger can be damaged by build-up or
corrosion due to sediment.
• Continual fresh make-up water will reduce boiler life.
Mineral buildup in the heat exchanger reduces heat
transfer, overheats the stainless steel heat exchanger,
and causes failure. Addition of oxygen carried in by
makeup water can cause internal corrosion in system
components. Leaks in boiler or piping must be repaired
at once to prevent makeup water.
CAUTION
CAUTION
Do not use petroleum-based cleaning or
sealing compounds in the boiler system.
Gaskets and seals in the system may be
damaged. This can result in substantial
property damage.
Do not use “homemade cures” or “boiler
patent medicines”. Serious damage to
the boiler, personnel, and/or property
may result.
Freeze protection fluids –
• NEVER use automotive antifreeze. Use only inhibited
propylene glycol solutions, which are specifically
formulated for hydronic systems. Ethylene glycol is
toxic and can attack gaskets and seals used in hydronic
systems.
3
The Knight Boiler - How it works...
Installation & Operation Manual
1. Stainless steel heat exchanger
Allows system water to flow through specially designed
coils for maximum heat transfer, while providing
protection against flue gas corrosion. The coils are
encased in a jacket that contains the combustion process.
2. Combustion chamber access cover
Allows access to the combustion side of the heat
exchanger coils.
3. Blower
The blower pulls in air and gas through the venturi (item
5). Air and gas mix inside the blower and are pushed into the
burner, where they burn inside the combustion chamber.
4. Gas valve
The gas valve senses the negative pressure created by the
blower, allowing gas to flow only if the gas valve is
powered and combustion air is flowing.
5. Venturi
The venturi controls air and gas flow into the burner.
6. Flue gas sensor (limit rated)
This sensor monitors the flue gas exit temperature. The control
module will modulate and shut down the boiler if flue gas
temperature gets too hot. This protects the flue pipe from
overheating.
7. Boiler outlet temperature sensor (housed with the
high limit sensor)
This sensor monitors boiler outlet water temperature (system
supply). If selected as the controlling sensor, the control
module adjusts boiler firing rate so the outlet temperature is
correct.
8. Boiler inlet temperature sensor
This sensor monitors return water temperature (system
return). If selected as the controlling sensor, the control
module adjusts the boiler firing rate so the inlet temperature is
correct.
9. Temperature and pressure gauge (field installed, not
shown)
Monitors the outlet temperature of the boiler as well as the
system water pressure.
10. Electronic LCD display
The electronic display consists of 4 buttons, a navigation dial
and a multiple line liquid crystal display.
11. Flue pipe adapter
Allows for the connection of the vent system to the
boiler.
12. Burner (not shown)
Made with metal fiber and stainless steel construction,
the burner uses pre-mixed air and gas and provides a
wide range of firing rates.
13. Water outlet (system supply)
NPT water connection that supplies hot water to the
system, either 1" or 1-1/4", depending on the
model.
14. Water inlet (system return)
NPT water connection that returns water from the
system to the heat exchanger, either 1" or 1-1/4",
depending on the model.
15. Gas connection pipe
Threaded pipe connection, either 1/2" or 3/4",
depending on the model. This pipe should be connected
to the incoming gas supply for the purpose of delivering
gas to the boiler.
4
16. SMART SYSTEM Control Module
The SMART SYSTEM Control responds to internal and
external signals and controls the blower, gas valve, and pumps
to meet the heating demand.
17. Manual air vent
Designed to remove trapped air from the heat exchanger
coils.
18. Air intake adapter
Allows for the connection of the PVC air intake pipe to
the boiler.
19. High voltage junction box
The junction box contains the connection points for the line
voltage power and all pumps.
20. Boiler drain port
Location from which the heat exchanger can be drained.
21. Low voltage connection board
The connection board is used to connect external low voltage
devices.
22. Low voltage wiring connections (knockouts)
Conduit connection points for the low voltage
connection board.
23. Condensate drain connection
Connects the condensate drain line to a 1/2" PVC union.
24. Access cover - front
Provides access to the gas train and the heat exchanger.
25. Ignition electrode
Provides direct spark for igniting the burner.
26. Flame inspection window
The quartz glass window provides a view of the burner
surface and flame.
27. Relief valve
Protects the heat exchanger from an over pressure condition.
The relief valve provided with the unit is set at 30 psi.
28. Flame sensor
Used by the control module to detect the presence of burner
flame.
29. Line voltage wiring connections (knockouts)
Conduit connection points for the high voltage junction box.
30. Top panel
Removable panel to gain access to the internal components.
31. Power switch
Turns 120 VAC ON/OFF to the boiler.
32. Leveling legs
Used to allow the heat exchanger to be leveled. This is needed
for the proper draining of the condensate from the combustion
chamber.
33. Air pressure switch
The air pressure switch detects blocked inlet conditions.
34. Transformer
The transformer provides 24V power to the integrated control.
35. High limit sensor (housed with the outlet
temperature sensor)
Device that monitors the outlet water temperature. If the
temperature exceeds its setting, the integrated control will
break the control circuit, shutting the boiler down.
36. Gas shutoff switch
An electrical switch designed to cut power to the gas valve to
prevent releasing any gas.
An electrical switch designed to shut down boiler operation in
the event the outer back of the heat exchanger, directly above the
flue connection exceeds 604°F (318°C). This is a one time
switch and could warrant a heat exchanger replacement. Check
the integrity of the rear refractory at the back of the upper coil if
the switch opens.
Maximum allowed working pressure is located on the rating plate.
MBH
(Note 5)
Heating
Capacity
MBH
(Note 2,7)
Net
AHRI
Ratings
Water,
MBH
(Note 3,7)
Notes:
1. As an Energy Star Partner, Lochinvar has determined that
Knight boilers meet the Energy Star guidelines for energy
efficiency.
2. The ratings are based on standard test procedures prescribed
by the United States Department of Energy.
3. Net AHRI ratings are based on net installed radiation of
sufficient quantity for the requirements of the building
and nothing need be added for normal piping and pickup.
Ratings are based on a piping and pickup allowance of 1.15.
4. Knight boilers require special gas venting. Use only
the vent materials and methods specified in the Knight
Installation and Operation Manual.
5. Standard Knight boilers are equipped to operate from sea
level to 4,500 feet only with no adjustments. The boiler
will de-rate by 4% for each 1,000 feet above sea level up to
4,500 feet.
6. High altitude Knight boilers are equipped to operate
from 3,000 to 12,000 feet only with no field adjustments.
The boiler will de-rate by 2% for each 1,000 feet above
3,000 feet. High altitude models are manufactured with
a different control module for altitude operation, but the
operation given in this manual remains the same as the
standard boilers. A high altitude label (as shown in FIG. A)
is also affixed to the unit.
7. Ratings have been confirmed by the Hydronics Section of
AHRI.
AFUE
%
(Note 1, 7)
Boiler
Water
Content
Gallons
0.61"1/2"3"3"
0.71"1/2"3"3"
1.31"1/2"3"3"
1.71"1/2"3"3"
2.41-1/4"3/4"4"4"
Water
Connections
Gas
Connections
Air
Size
Vent
Size
(Note 4)
8. Knight boilers comply with the requirements of CSD-1
Section CW-400 requirements as a temperature operation
control. The manual reset high limit provided with the
Knight is listed to UL353.
UNIT EQUIPPED FOR
HIGH ALTITUDE
3,000 FT. TO 12,000 FT.
Figure A High Altitude Label Location
7
1 Determine boiler location
Installation must comply with:
• Local, state, provincial, and national codes, laws,
regulations, and ordinances.
• National Fuel Gas Code, ANSI Z223.1 – latest edition.
• Standard for Controls and Safety Devices for Automatically
Fired Boilers, ANSI/ASME CSD-1, when required.
• National Electrical Code.
• For Canada only: B149.1 Installation Code, CSA C22.1
Canadian Electrical Code Part 1 and any local codes.
NOTICE
Before locating the boiler, check:
1. Check for nearby connection to:
• System water piping
• Venting connections
• Gas supply piping
• Electrical power
2. 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
appliance. The pan must not restrict combustion air
flow. Under no circumstances is the manufacturer to be
held responsible for water damage in connection with
this appliance, or any of its components.
3. Check area around the boiler. Remove any combustible
materials, gasoline and other flammable liquids.
WARNING
4. The Knight boiler must be installed so that gas control
system components are protected from dripping or
spraying water or rain during operation or service.
5. If a new boiler will replace an existing boiler, check for
and correct system problems, such as:
• System leaks causing oxygen corrosion or heat exchanger
cracks from hard water deposits.
• Incorrectly-sized expansion tank.
• Lack of freeze protection in boiler water causing system
and boiler to freeze and leak.
8
The Knight boiler gas manifold and
controls met safe lighting and other
performance criteria when the boiler
underwent tests specified in ANSI Z21.13
– latest edition.
Failure to keep boiler area clear and free
of combustible materials, gasoline, and
other flammable liquids and vapors can
result in severe personal injury, death, or
substantial property damage.
Installation & Operation Manual
WARNING
WARNING
Closet and alcove installations
A closet is any room the boiler is installed in which is less
than 67 cubic feet for KBN081 and KBN106 models, 86 cubic
feet for KBN151 models, 107 cubic feet for KBN211 models,
and 120 cubic feet for KBN286 models.
An alcove is any room which meets the criteria for a closet
with the exception that it does not have a door.
Example: Room dimensions = 4 feet long, 3 feet wide, and
8 foot ceiling = 4 x 3 x 8 = 96 cubic feet. This would be
considered a closet for a Knight Boiler.
WARNING
Provide clearances:
Clearances from combustible materials
1. Hot water pipes—at least 1/4" (6 mm) from combustible
materials.
2. Vent pipe – at least 1" (25 mm) from combustible
materials.
3. See FIG.’s 1-1 and 1-2 on page 9 for other clearance
minimums.
Clearances for service access
1. See FIG.’s 1-1 and 1-2 on page 9 for recommended
service clearances. If you do not provide the minimum
clearances shown, it may not be possible to service the
boiler without removing it from the space.
This appliance is certified as an indoor
appliance. Do not install the appliance
outdoors or locate where the appliance will
be exposed to freezing temperatures or to
temperatures that exceed 100°F.
Do not install the appliance where the
relative humidity may exceed 93%. Do not
install the appliance where condensation
may form on the inside or outside of the
appliance, or where condensation may fall
onto the appliance.
Failure to install the appliance indoors
could result in severe personal injury,
death, or substantial property damage.
This appliance requires a special venting
system. If using PVC the vent connection
to the appliance must be made with the
starter CPVC pipe section provided with
the appliance. The field provided vent
fittings must be cemented to the CPVC
pipe section. Use only the vent materials,
primer and cement specified in this manual
to make the vent connections. Failure to
follow this warning could result in fire,
personal injury, or death.
For closet and alcove installations as shown
in FIG.’s 1-1 and 1-2, CPVC, polypropylene
or stainless steel vent material must be
used inside the structure. The ventilating
air openings shown in FIG.’s 1-1 and 1-2
are required for this arrangement. Failure
to follow this warning could result in fire,
personal injury, or death.
For closet installations, CPVC,
polypropylene or stainless steel
vent material MUST BE used in
a closet structure due to elevated
temperatures. Failure to follow
6"
VENTILATING*
AIR OPENING
CLOSED DOOR
VENTILATING*
AIR OPENING
6"
RIGHT
this warning could result in fire,
personal injury, or death.
0"
*AREA OF EACH OPENING:
1 SQ. INCH PER 1000 BTU PER HOUR INPUT
WITH A MINIMUM OF 100 SQ. INCHES.
For alcove installations, CPVC,
polypropylene or stainless steel
vent material MUST BE used
in an alcove structure due to
elevated temperatures. Failure to
follow this warning could result
in fire, personal injury, or death.
OPEN
12”
LEFT
14”
REAR
FRONT
0”
RIGHT
RECOMMENDED SERVICE CLEARANCES:
FRONT - 24”
TOP - 24”
LEFT SIDE - 24”
REAR - 24”
18”
FRONT
9
1 Determine boiler location
Installation & Operation Manual
Provide air openings to room:
Knight boiler alone in boiler room
1. No air ventilation openings into the boiler room are
needed when clearances around the Knight boiler are
at least equal to the SERVICE clearances shown in
FIG.’s 1-1 and 1-2. For spaces that do NOT supply this
clearance, provide two openings as shown in FIG. 1-1.
Each opening must provide one square inch free area per
1,000 Btu/hr of boiler input.
Knight boiler in same space with other gas or oilfired appliances
1. Follow the National Fuel Gas Code (U.S.) or CSA B149.1
(Canada) to size/verify size of the combustion/ventilation
air openings into the space.
WARNING
2. Size openings only on the basis of the other appliances in
the space. No additional air opening free area is needed
for the Knight boiler because it takes its combustion air
from outside (direct vent installation).
The space must be provided with
combustion/ventilation air openings
correctly sized for all other appliances
located in the same space as the Knight
boiler.
Do not install the boiler in an attic.
Failure to comply with the above warnings
could result in severe personal injury,
death, or substantial property damage.
Flooring and foundation
Flooring
The Knight boiler is approved for installation on combustible
flooring, but must never be installed on carpeting.
WARNING
If flooding is possible, elevate the boiler sufficiently to prevent
water from reaching the boiler.
Do not install the boiler on carpeting even
if foundation is used. Fire can result,
causing severe personal injury, death, or
substantial property damage.
10
Residential garage installation
Precautions
Take the following precautions when installing the appliance
in a residential garage. If the appliance is located in a
residential garage, it should be installed in compliance with
the latest edition of the National Fuel Gas Code, ANSI Z223.1
and/or CAN/CGA-B149 Installation Code.
• Appliances located in residential garages and in
adjacent spaces that open to the garage and are not part
of the living space of a dwelling shall be installed so that
all burners and burner ignition devices are located not
less than 18 inches (46 cm) above the floor.
• The appliance shall be located or protected so that it is
not subject to physical damage by a moving vehicle.
Vent and air piping
The Knight boiler requires a special vent system, designed for
pressurized venting.
The boiler is to be used for either direct vent installation or
for installation using indoor combustion air. When room
air is considered, see Section 3, General Venting. Note
prevention of combustion air contamination below when
considering vent/air termination.
Vent and air must terminate near one another and may be
vented vertically through the roof or out a side wall, unless
otherwise specified. You may use any of the vent/air piping
methods covered in this manual. Do not attempt to install
the Knight boiler using any other means.
Be sure to locate the boiler such that the vent and air piping
can be routed through the building and properly terminated.
The vent/air piping lengths, routing and termination method
must all comply with the methods and limits given in this
manual.
Prevent combustion air contamination
Install air inlet piping for the Knight boiler as described in this
manual. Do not terminate vent/air in locations that can allow
contamination of combustion air. Refer to Table 1A, page
11 for products and areas which may cause contaminated
combustion air.
WARNING
You must pipe combustion air to the boiler
air intake. Ensure that the combustion air
will not contain any of the contaminants
in Table 1A, page 11. Contaminated
combustion air will damage the boiler,
resulting in possible severe personal
injury, death or substantial property
damage. Do not pipe combustion air near
a swimming pool, for example. Also,
avoid areas subject to exhaust fumes from
laundry facilities. These areas will always
contain contaminants.
1 Determine boiler location (continued)
Installation & Operation Manual
Table 1A Corrosive Contaminants and Sources
Products to avoid:
Spray cans containing chloro/fluorocarbons
Permanent wave solutions
Chlorinated waxes/cleaners
Chlorine-based swimming pool chemicals
Calcium chloride used for thawing
Sodium chloride used for water softening
Refrigerant leaks
Paint or varnish removers
Hydrochloric acid/muriatic acid
Cements and glues
Antistatic fabric softeners used in clothes dryers
Chlorine-type bleaches, detergents, and cleaning solvents
found in household laundry rooms
Adhesives used to fasten building products and other
similar products
Areas likely to have contaminants
Dry cleaning/laundry areas and establishments
Swimming pools
Metal fabrication plants
Beauty shops
Refrigeration repair shops
Photo processing plants
Auto body shops
Plastic manufacturing plants
Furniture refinishing areas and establishments
New building construction
Remodeling areas
Garages with workshops
When using an existing vent system to
install a new boiler:
WARNING
Check the following venting components before installing:
• Material - For materials listed for use with this appliance,
see Section 3 - General Venting. For polypropylene or
stainless steel venting, an adapter of the same
manufacturer must be used at the flue collar connection.
• Size - To ensure proper pipe size is in place, see Table 3A.
Check to see that this size is used throughout the vent
system.
• Manufacturer - For a stainless steel or polypropylene
application, you must use only the listed manufacturers
and their type product listed in Tables 3E and 3G for CAT
IV positive pressure venting with flue producing
condensate.
• Supports - Non-combustible supports must be in place
allowing a minimum 1/4" rise per foot. The supports
should adequately prevent sagging and vertical slippage,
by distributing the vent system weight. For additional
information, consult the vent manufacturer’s
instructions for installation.
• Terminations - Carefully review Sections 3 through 5 to
ensure requirements for the location of the vent and air
terminations are met and orientation of these fit the
appropriate image from the Sidewall or Vertical
options listed in the General Venting Section. For
stainless steel vent, only use terminations listed in Table
3H for the manufacturer of the installed vent.
• Seal - With prior requirements met, the system should be
tested to the procedure listed in parts (c) through (f) of
the Removal of an Existing Boiler Section on page 12.
With polypropylene and stainless steel vent, seal and connect
all pipe and components as specified by the vent manufacturer
used; with PVC/CPVC vent, see the Installing Vent or Air
Piping Section on page 19.
WARNING
Failure to follow all instructions can result
in flue gas spillage and carbon monoxide
emissions, causing severe personal injury
or death.
If any of these conditions are not met,
the existing system must be updated or
replaced for that concern. Failure to
follow all instructions can result in flue gas
spillage and carbon monoxide emissions,
causing severe personal injury or death.
11
1 Determine boiler location
When removing a boiler from existing
common vent system:
Installation & Operation Manual
DANGER
WARNING
At the time of removal of an existing boiler, the following steps
shall be followed with each appliance remaining connected
to the common venting system placed in operation, while
the other appliances remaining connected to the common
venting system are not in operation.
a. Seal any unused openings in the common venting system.
b. Visually inspect the venting system for proper size and
horizontal pitch and determine there is no blockage
or restriction, leakage, corrosion, or other deficiencies,
which could cause an unsafe condition.
c. Test vent system – 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.
Do not install the Knight boiler into a
common vent with any other appliance.
This will cause flue gas spillage or appliance
malfunction, resulting in possible severe
personal injury, death, or substantial
property damage.
Failure to follow all instructions can result
in flue gas spillage and carbon monoxide
emissions, causing severe personal injury
or death.
g. Any improper operation of the common venting system
should be corrected so the installation conforms with the
National Fuel Gas Code, ANSI Z223.1/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 and/or CAN/CSA B149.1, Natural Gas
and Propane Installation Code.
d. Place in operation the appliance being inspected. Follow
the lighting instructions. Adjust thermostat so appliance
will operate continuously.
e. Test for spillage at the draft hood relief opening after
5 minutes of main burner operation. Use the flame of a
match or candle, or smoke from a cigarette, cigar, or pipe.
f. After it has been determined that each appliance
remaining connected to the common venting system
properly vents when tested as outlined herein, return
doors, windows, exhaust fans, fireplace dampers, and any
other gas-burning appliance to their previous conditions
of use.
12
2 Prepare boiler
Remove boiler from wood pallet
1. After removing the outer shipping carton from the boiler,
remove the parts box.
2. Remove the front door to access the lag bolts in front of
the unit (FIG. 2-1).
3. To remove the boiler from the pallet (after removing the
front door):
a. Remove the two lag bolts from the wood pallet
inside the boiler (FIG. 2-1).
b. Detach the boiler from the lag bolts in the rear of the
unit, see FIG. 2-1.
NOTICE
Figure 2-1 Boiler Mounted on Shipping Pallet
Do not drop the boiler or bump the jacket
on the floor or pallet. Damage to the
boiler can result.
Installation & Operation Manual
5. After installation is complete, attach the propane conversion
label (in the conversion kit bag) next to the boiler rating
plate. Attach the LP caution label (in the conversion kit
bag) to the left side of the unit in the lower left corner.
6. Replace the top and front access covers.
Table 2A LP Conversion Table
LP Conversion Table
ModelLP Orifice Stamping
8180
106105
151150
211210 / W150
286285
WARNING
After converting to LP, check combustion
per the Start-up procedure in Section 10
of this manual. Failure to check and verify
combustion could result in severe personal
injury, death, or substantial property damage.
. 2
Gas conversions
WARNING
1. Remove the top and front access covers from the unit (no
tools required for removal).
2. Remove the three screws securing the gas valve to the
venturi (FIG. 2-2).
3. Locate the propane orifice disk from the conversion kit
bag. Verify that the stamping on the orifice disk matches
the boiler size (see Table 2A).
Place the orifice into the black rubber grommet in the
side of the gas valve and secure in the valve (FIG. 2-2).
4. Reposition the gas valve against the venturi and replace
the screws (FIG. 2-2) securing the valve to the venturi.
For a boiler already installed, you must
turn off gas supply, turn off power and
allow boiler to cool before proceeding.
You must also completely test the boiler
after conversion to verify performance
as described under Start-up, Section 10
of this manual. Failure to comply could
result in severe personal injury, death, or
substantial property damage.
You must install a propane orifice to
operate the Knight boiler on propane gas.
Verify when installing that the orifice size
marking matches boiler size (Table 2A).
Figure 2-2 Installing Propane Orifice
Leveling the boiler
1. Set the boiler in place and check level.
a) Adjust legs if necessary to level boiler, see FIG. 2-3
below.
Figure 2-3 Leveling Legs on the Boiler
13
3 Generalventing
Direct venting options - Sidewall Vent
Installation & Operation Manual
Figure 3-1 Two-Pipe Sidewall Termination - See
page 22 for more details
Direct venting options - Vertical Vent
Figure 3-2 PVC/CPVC Concentric Sidewall
Termination - See page 26 for more details
Figure 3-3 Two-Pipe Vertical
Termination - See page 29 for
more details
14
Figure 3-4 PVC/CPVC Concentric
Vertical Termination - See page 31
for more details
Figure 3-5 Vertical Vent, Sidewall
Air - See page 21 for more details
3 Generalventing (continued)
Install vent and combustion air piping
Installation & Operation Manual
DANGER
WARNING
WARNING
NOTICE
WARNING
The Knight boiler must be vented and
supplied with combustion and ventilation
air as described in this section. Ensure the
vent and air piping and the combustion
air supply comply with these instructions
regarding vent system, air system, and
combustion air quality. See also Section 1
of this manual.
Inspect finished vent and air piping
thoroughly to ensure all are airtight and
comply with the instructions provided and
with all requirements of applicable codes.
Failure to provide a properly installed vent
and air system will cause severe personal
injury or death.
This appliance requires a special venting
system. Use only approved stainless steel,
PVC, CPVC or polypropylene pipe and
fittings listed in Tables 3D, 3E, and 3G for
vent pipe, and fittings. Failure to comply
could result in severe personal injury,
death, or substantial property damage.
DO NOT mix components from different
systems. The vent system could fail,
causing leakage of flue products into the
living space. Mixing of venting materials
will void the warranty and certification of
the appliance.
Installation must comply with local
requirements and with the National
Fuel Gas Code, ANSI Z223.1 for U.S.
installations or CSA B149.1 for Canadian
installations.
For closet and alcove installations, CPVC,
polypropylene or stainless steel material
MUST BE used in a closet/alcove structure.
Failure to follow this warning could result
in fire, personal injury, or death.
The Knight boiler vent and air piping can be installed through
the roof or through a sidewall. Follow the procedures in this
manual for the method chosen. Refer to the information in
this manual to determine acceptable vent and air piping length.
You may use any of the vent/air piping methods covered in this
manual. Do not attempt to install the Knight boiler using any
other means.
You must also install air piping from outside to the boiler
air intake adapter unless following the Optional Room Air
instructions on page 21 of this manual. The resultant installation
is direct vent (sealed combustion).
Air intake/vent connections
1. Combustion Air Intake Connector (FIG. 3-6) - Used to
provide combustion air directly to the unit from outdoors. A
fitting is provided on the unit for final connection.
Combustion air piping must be supported per guidelines
listed in the National Mechanical Code, Section 305, Table
305.4 or as local codes dictate.
2. Vent Connector (FIG.'s 3-7 thru 3-9) - Used to provide a
passageway for conveying combustion gases to the
outside. A transition fitting is provided on the unit for
final connection. Vent piping must be supported per the
National Building Code, Section 305, Table 305.4 or as
local codes dictate.
Figure 3-6 Near Boiler Air Piping
AIR
CAUTION
NOTICE
WARNING
Improper installation of venting systems
may result in injury or death.
Follow the instructions in Section 1, page
12 of this manual when removing a boiler
from an existing vent system.
Do not connect any other appliance to
the vent pipe or multiple boilers to a
common vent pipe. Failure to comply
could result in severe personal injury,
death, or substantial property damage.
15
3 Generalventing
Installation & Operation Manual
Requirements for installation in
Canada
1. Installations must be made with a vent pipe system
certified to ULC-S636.
2. The first three (3) feet of plastic vent pipe from the
appliance flue outlet must be readily accessible for visual
inspection.
3. The components of the certified vent system must not be
interchanged with other vent systems or unlisted
pipe/fittings. For concentric vent installations, the inner
vent tube must be replaced with field supplied certified vent
material to comply with this requirement.
4. The 3" Concentric Vent Kit available from Lochinvar (see
Section 4 – Sidewall Termination – Optional Concentric Vent) and the 3" Concentric Vent Kit available from IPEX
are both approved for use on the Knight boiler. Both
kits are listed to the ULC-S636 standard for use in Canada.
Sizing
The Knight boiler uses model specific combustion air intake
and vent piping sizes as detailed in Table 3A below.
Table 3A Air Intake/Vent Piping Sizes
Minimum / Maximum allowable
combustion air and vent piping lengths
are as follows:
Combustion Air = 12 equivalent feet minimum / 100
equivalent feet maximum
The appliance output rating will reduce
by up to 1.5% for each 25 feet of vent
length.
Equivalent Vent
Length
ModelAir IntakeVent
81 - 2113 inches3 inches
2864 inches4 inches
NOTICE
Increasing or decreasing combustion air or
vent piping sizes is not authorized.
286CVK30073 feet
16
3 Generalventing (continued)
Materials
Air inlet pipe materials:
The air inlet pipe(s) must be sealed. Choose acceptable
combustion air inlet pipe materials from the following list:
PVC, CPVC, Polypropylene or ABS
Dryer Vent or Sealed Flexible Duct (not recommended
for rooftop air inlet)
Galvanized steel vent pipe with joints and seams sealed as
specified in this section.
Type “B” double-wall vent with joints and seams sealed as
specified in this section.
AL29-4C, stainless steel material to be sealed to
specification of its manufacturer.
*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
NOTICE
Using air intake materials other than
those specified can result in personal
injury, death or property damage.
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.
Installation & Operation Manual
The PVC, CPVC, or ABS air inlet pipe should be cleaned and
sealed with the pipe manufacturer’s 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 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.
Follow the polypropylene manufacturer's instructions when
using polypropylene material as an inlet pipe.
When a sidewall or vertical rooftop 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.
Sealing of Type “B” double-wall vent material or galvanized
vent pipe material used for air inlet piping on a sidewall or
vertical rooftop 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 silicone 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 (3) 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.
17
3 Generalventing
Installation & Operation Manual
Optional room air
NOTICE
Commercial applications utilizing the Knight boiler may
be installed with a single pipe carrying the flue products to
the outside while using combustion air from the equipment
room. In order to use the room air venting option the
following conditions and considerations must be followed.
• The unit MUST be installed with the appropriate
room air kit (Table 3C).
• The equipment room MUST be provided with
properly sized openings to assure adequate
combustion air. Please refer to instructions provided
with the room air kit.
• There will be a noticeable increase in the noise level
during normal operation from the inlet air opening.
• Using the room air kit makes the unit vulnerable to
combustion air contamination from within the
building. Please review Section 1, Prevent
Combustion Air Contamination, to ensure proper
installation.
• Vent system and terminations must comply with the
standard venting instructions set forth in this
manual.
Optional room air is intended for
commercial applications. Combustion
air piping to the outside is recommended
for residential applications.
Air contamination
Pool and laundry products and common household and hobby
products often contain fluorine or chlorine compounds. When
these chemicals pass through the boiler, they can form strong
acids. The acid can eat through the boiler wall, causing serious
damage and presenting a possible threat of flue gas spillage or
boiler water leakage into the building.
Please read the information given in Table 1A, page 11,
listing contaminants and areas likely to contain them. If
contaminating chemicals will be present near the location of the
boiler combustion air inlet, have your installer pipe the boiler
combustion air and vent to another location, per this manual.
WARNING
WARNING
If the boiler combustion air inlet is located in
a laundry room or pool facility, for example,
these areas will always contain hazardous
contaminants.
To prevent the potential of severe personal
injury or death, check for areas and products
listed in Table 1A, page 11 before installing
the boiler or air inlet piping.
If contaminants are found, you MUST:
• Remove contaminants permanently.
—OR—
• Relocate air inlet and vent terminations
to other areas.
WARNING
Table 3C Optional Room Air Kit
Model Kit Number
81 - 211KIT30052
286KIT30053
When utilizing the single pipe method,
provisions for combustion and ventilation
air must be in accordance with Air for
Combustion and Ventilation, of the latest
edition of the National Fuel Gas Code,
ANSI Z223.1, in Canada, the latest edition
of CGA Standard B149 Installation
Code for Gas Burning Appliances and
Equipment, or applicable provisions of
the local building codes.
18
3 Generalventing (continued)
Installation & Operation Manual
PVC/CPVC
This product has been approved for use with the PVC/CPVC
vent materials listed in Table 3D.
Installing vent and air piping
WARNING
NOTICE
NOTICE
WARNING
Table 3D PVC/CPVC Vent Pipe, and Fittings
The vent connection to the appliance must
be made with the starter CPVC pipe section
provided with the appliance if PVC/CPVC
vent is to be used. The field provided
vent fittings must be cemented to the
CPVC pipe section using an “All Purpose
Cement” suitable for PVC and CPVC pipe.
Use only the vent materials, primer, and
cement specified in Table 3D to make
the vent connections. Failure to follow
this warning could result in fire, personal
injury, or death.
Use only cleaners, primers, and solvents
that are approved for the materials which
are joined together.
All PVC vent pipes must be glued, properly
supported, and the exhaust must be
pitched a minimum of a 1/4 inch per foot
back to the boiler (to allow drainage of
condensate).
Insulation should not be used on PVC
or CPVC venting materials. The use of
insulation will cause increased vent wall
temperatures, which could result in vent
pipe failure.
1. Work from the boiler to vent or air termination. Do not
exceed the lengths given in this manual for the air or vent
piping.
2. Cut pipe to the required lengths and deburr the inside
and outside of the pipe ends.
3. Chamfer outside of each pipe end to ensure even
cement distribution when joining.
4. Clean all pipe ends and fittings using a clean dry rag.
(Moisture will retard curing and dirt or grease will prevent
adhesion.)
5. Dry fit vent or air piping to ensure proper fit up before
assembling any joint. The pipe should go a third to
two-thirds into the fitting to ensure proper sealing after
cement is applied.
6. Priming and Cementing:
a. Handle fittings and pipes carefully to prevent
contamination of surfaces.
b. Apply a liberal even coat of primer to the fitting
socket and to the pipe end to approximately 1/2"
beyond the socket depth.
c. Apply a second primer coat to the fitting socket.
d. While primer is still wet, apply an even coat of
approved cement to the pipe equal to the depth of
the fitting socket along with an even coat of
approved cement to the fitting socket.
e. Apply a second coat of cement to the pipe.
f. While the cement is still wet, insert the pipe into
the fitting, if possible twist the pipe a 1/4 turn as
you insert it. NOTE: If voids are present,
sufficient cement was not applied and joint could
be defective.
g. Wipe excess cement from the joint removing ring or
beads as it will needlessly soften the pipe.
Figure 3-7 Near Boiler PVC/CPVC Venting
NOTE: In Canada, CPVC and PVC vent pipe, fi ttings and cement/
primer must be ULC-S636 certifi ed.
19
3 Generalventing
Polypropylene
This product has been approved for use with polypropylene
vent with the manufacturers listed in Table 3E.
All terminations must comply with listed options in this manual
and be a single-wall vent offering.
For use of flex pipe, it is recommended to have the vent material
in 32°F or higher ambient space before bending at installation.
No bends should be made to greater than 45° and ONLY
installed in vertical or near vertical installations.
For support and special connections required, see the
manufacturer's instructions. All vent is to conform to standard
diameter and equivalent length requirements established.
Table 3E Polypropylene Vent Pipe and Fittings
Approved Polypropylene Vent Manufacturers
MakeModel
Centrotherm Eco Systems
Duravent (M & G Group)
PolyPro Single-Wall / PolyPro Flex
InnoFlue SW/Flex
Installation & Operation Manual
WARNING
NOTICE
NOTICE
Use only the adapters and vent system listed
in Tables 3E and 3F. DO NOT mix vent
systems of different types or manufacturers.
Failure to comply could result in severe
personal injury, death, or substantial
property damage.
Installations must comply with applicable
national, state, and local codes. For
Canadian installation, polypropylene vent
must be listed as a ULC-S636 approved
system.
Installation of a polypropylene vent system
should adhere to the vent manufacturer’s
installation instructions supplied with the
vent system.
NOTICE
NOTICE
WARNING
Table 3F Approved PolypropyleneTerminations
The installer must use a specific vent starter
adapter at the flue collar connection.
This adapter is supplied by the vent
manufacturer to adapt to its vent system.
See Table 3F for approved vent adapters.
Discard CPVC starter piece.
All vent connections MUST be secured by
the vent manufacturer's joint connector
(FIG. 3-8).
Insulation should not be used on
polypropylene venting materials. The use
of insulation will cause increased vent wall
temperatures, which could result in vent
pipe failure.
Figure 3-8 Near Boiler Polypropylene Venting
POLYPROPYLENE ADAPTER
JOINT CONNECTOR REQUIRED AT ALL
COMPONENT CONNECTIONS OF VENT SYSTEM
IMG00015
Centrotherm InnoFlue SW
Model
81 - 211
286
* These parts are only needed if the sidewall termination assembly is used (see FIG. 4-4B on page 24).
This product has been approved for use with stainless steel
using the manufacturers listed in Table 3G.
WARNING
Use only the materials, vent systems, and
terminations listed in Tables 3G and 3H.
DO NOT mix vent systems of different
types or manufacturers. Failure to comply
could result in severe personal injury,
death, or substantial property damage.
Installation & Operation Manual
NOTICE
Figure 3-9 Near Boiler Stainless Steel Venting
Installation of a stainless steel vent system
should adhere to the stainless steel vent
manufacturer’s installation instructions
supplied with the vent system.
NOTICE
NOTICE
Table 3G Stainless Steel Vent Pipe and Fittings
Dura Vent (M & G Group)FasNSeal Vent / FasNSeal Flex* Vent
Z-Flex (Nova Flex Group)Z-Vent
Heat Fab (Selkirk Corporation)Saf-T Vent
The installer must use a specific vent starter
adapter at the flue collar connection,
supplied by the vent manufacturer to
adapt to its vent system. See Table 3H for
approved vent adapters. Discard CPVC
starter piece.
Installations must comply with applicable
national, state, and local codes. Stainless
steel vent systems must be listed as a
UL-1738 approved system for the United
States and a ULC-S636 approved system
for Canada.
Approved Stainless Steel Vent Manufacturers
MakeModel
S.S. ADAPTER
*Use of FasNSeal Flex smooth inner wall vent is to be used in vertical or near vertical sections only, taking precaution to ensure
no sagging occurs of the vent system. Connect to the FasNSeal rigid vent using specially designed adapters and sealing method,
see manufacturer’s instructions.
Table 3H Approved Stainless Steel (S.S.) Terminations and Adapters
ProTechHeat FabZ Flex
FasNSealSaf-T VentZ-Vent
Model
81 - 211
286
S.S.
Adapter
300715
F303759
Flue
Termination
FSBS3
FSRC3(R.C)
FSBS4
FSRC4(R.C.)
Intake Air
Termination
3038899301PVC
FSAIH04
303888
Adapter
9401PVC
S.S.
Flue
Termination
9392
5300CI
9492
5400CI
Intake Air
Termination
9314TERM2SVSLA03
9414TERM2SVSLA04
S.S.
Adapter
Flue
Termination
2SVSTP03
2SVSRCX03
2SVSTP04
2SVSRCX04
Intake Air
Termination
2SVSTEX0390
2SVSTEX0490
21
4 Sidewall directventing
Installation & Operation Manual
Vent/air termination – sidewall
WARNING
WARNING
Determine location
Locate the vent/air terminations using the following guidelines:
1. The total length of piping for vent or air must not exceed
the limits given in the General Venting Section on page 16
of this manual.
2. You must consider the surroundings when terminating
the vent and air:
a. Position the vent termination where vapors will
not damage nearby shrubs, plants or air
conditioning equipment or be objectionable.
b. The flue products will form a noticeable plume as
they condense in cold air. Avoid areas where the
plume could obstruct window views.
c. Prevailing winds could cause freezing of
condensate and water/ice buildup where flue
products impinge on building surfaces or plants.
d. Avoid possibility of accidental contact of flue
products with people or pets.
e. Do not locate the terminations where wind eddies
could affect performance or cause recirculation,
such as inside building corners, near adjacent
buildings or surfaces, window wells, stairwells,
alcoves, courtyards, or other recessed areas.
WARNING
f. Do not terminate above any door or window.
Condensate can freeze, causing ice formations.
g. Locate or guard vent to prevent condensate damage
to exterior finishes.
Follow instructions below when
determining vent location to avoid
possibility of severe personal injury,
death, or substantial property damage.
A gas vent extending through an exterior
wall shall not terminate adjacent to a wall
or below building extensions such as eaves,
parapets, balconies, or decks. Failure to
comply could result in severe personal
injury, death, or substantial property
damage.
Sidewall vent and air inlet terminations
must terminate in the same pressure zone.
Figure 4-1A PVC/CPVC/ Polypropylene Sidewall
Termination of Air and Vent w/Field Supplied Fittings
FACTORY PROVIDED
BIRD SCREEN
FACTORY PROVIDED
BIRD SCREEN
If using the sidewall termination:
3. The air piping must terminate in a down-turned elbow
as shown in FIG. 4-1A. This arrangement avoids
recirculation of flue products into the combustion air
stream.
4. The vent piping must terminate in an elbow pointed
outward or away from the air inlet, as shown in FIG. 4-1A.
WARNING
Do not exceed the maximum lengths of the
outside vent piping shown in FIG. 4-1A.
Excessive length exposed to the outside
could cause freezing of condensate in the
vent pipe, resulting in potential boiler
shutdown.
When venting out a sidewall using PVC, CPVC, or Polypropylene
vent materials, an optional sidewall vent termination kit can be
ordered (reference Table 4A for kit numbers).
Table 4A Alternate Sidewall Vent Kits
ModelKit NumberVent Size
81 - 211KIT300453 inch vent
286KIT300464 inch vent
Figure 4-1B Alternate PVC/CPVC/Polypropylene
Sidewall Termination of Air and Vent
6. Locate terminations so they are not likely to be damaged
by foreign objects, such as stones or balls, or subject to
buildup of leaves or sediment.
Figure 4-2A Clearance to Gravity Air Inlets
Installation & Operation Manual
12”
BIRD
SCREEN
GRADE OR
SNOW LINE
ALTERNATE VENTING ARRANGEMENT
(IF SPACE PERMITS)
MIN
Figure 4-1D Alternate SS Venting Arrangement Typical Stainless Steel Sidewall Termination of Air and
Vent w/Field Supplied Fittings, Utilizing a Hood Intake
TO BOILER
INTAKE AIR
CONNECTION
FROM BOILER
VENT PIPE
CONNECTION
GRADE OR
SNOW LINE
BIRD SCREEN
12" (305 MM) MIN
15" (381 MM) MAX
12" (305 MM) MIN
5. Maintain clearances as shown in FIG.’s 4-1A thru 4-3B,
pages 22 - 24. Also maintain the following:
a. Vent must terminate:
• At least 6 feet from adjacent walls.
• No closer than 12 inches below roof overhang.
• At least 7 feet above any public walkway.
• At least 3 feet above any forced air intake within
10 feet.
• No closer than 12 inches below or horizontally
from any door or window or any other gravity air
inlet.
b. Air inlet must terminate at least 12 inches above
grade or snow line; at least 12 inches below the vent
termination; and the vent pipe must not extend
more than 24 inches vertically outside the building
as shown in FIG. 4-1B. Condensate could freeze and
block vent pipe.
c. Do not terminate closer than 4 feet horizontally
from any electric meter, gas meter, regulator, relief
valve, or other equipment. Never terminate above or
below any of these within 4 feet horizontally.
12"
MIN.
VENT / AIR
TERMINATION
12"
MIN.
12"
MIN.
Figure 4-2B Alternate Clearance to Gravity Air Inlets w/
Field Supplied Fittings
12”
MIN.
BIRD
SCREEN
(TYPICAL)
12”
MIN.
12”
MIN.
Figure 4-3A Clearance to Forced Air Inlets
IF LESS
THAN 10’
VENT / AIR
TERMINATION
7' MIN. ABOVE ANY
PUBLIC WALKWAY
36"
MIN.
FORCED AIR
INLET
23
4 Sidewall direct venting
A
Installation & Operation Manual
Figure 4-3B Alternate Clearance to Forced Air Inlets w/
1. Use the factory supplied wall plate as a template to locate
the vent and air intake holes and mounting holes.
Air pipe penetration:
a. Cut a hole for the air pipe. Size the air pipe hole as
close as desired to the air pipe outside diameter.
Vent pipe penetration:
a. Cut a hole for the vent pipe. For either combustible
or noncombustible construction, size the vent pipe
hole with at least a 1/2 inch clearance around the
vent pipe outer diameter:
• 4½ inch hole for 3 inch vent pipe
• 5½ inch hole for 4 inch vent pipe
Drill 3/16" diameter holes for inserting the plastic anchors
into the wall.
2. For Polypropylene Only: Install the vent and air intake
sidewall adapters from Table 3F on page 20 into the vent
plate. Slide the sidewall retaining bracket down the
sidewall adapters flush to the vent plate (FIG. 4-4B).
3. For PVC/CPVC Only: Install the vent and air intake
piping through the wall into the vent plate openings.
Use RTV silicone sealant to seal the air pipe. Use the
cement/primer listed in Table 3D on page 19 to seal the
vent pipe.
4. Mount and secure the vent plate to the wall, using stainless
steel screws.
5. Seal all gaps between the pipes and wall. Seal around the
plate to the wall assuring no air gaps.
6. Assemble the vent cap to the vent plate (see FIG.'s 4-4A
and 4-4B). Insert the stainless steel screws into the vent
cap screw hole openings and securely attach the vent cap
to the vent plate.
7. Seal all wall cavities.
8. PVC/CPVC terminations are designed to accommodate
any wall thickness of standard constructions per the
directions found in this manual.
9. Stainless steel terminations are designed to penetrate
walls with a thickness up to 9.25 inches of standard
construction.