Installation & Operation Manual
1Determine boiler location
Provide air openings to room:
Knight XL alone in boiler room
1.No air ventilation openings into the boiler room are needed when clearances around the Knight XL are at least equal to the SERVICE clearances shown in FIG.’s
Knight XL in same space with other gas or
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.
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
•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
WARNING
The space must be provided with combustion/ventilation air openings correctly sized for all other appliances located in the same space as the Knight XL.
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.
The Knight XL 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 the General Venting Section. 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
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 XL because it takes its combustion air from outside (direct vent installation).
Flooring and foundation
Flooring
The Knight XL is approved for installation on combustible flooring, but must never be installed on carpeting.
WARNING Do not install the boiler on carpeting even if foundation is used. Fire can result,
causing severe personal injury, death, or substantial property damage.
methods covered in this manual. Do not attempt to install the Knight XL 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 XL 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.
If flooding is possible, elevate the boiler sufficiently to prevent water from reaching the boiler.
10 
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.
