CATEGORY 1 - 450 F. MAX. VENT TEMP.
The venting system must be installed in accordance with Section 5.3, Air for Combustion and Ventilation, of the National Fuel Gas Code Z223.1/NFPA 54 (latest edition), or Sections 7.2, 7.3 or 7.4 of CSA B149.1, National Gas and Propane Codes (latest edition) or applicable provisions of the local building code and these instructions.
The furnace shall be connected to any type of B, BW or L vent connec- tor, and shall be connected to a factory-built or masonry chimney. The furnace shall not be connected to a chimney flue serving a sepa- rate appliance designed to burn solid fuel.
It is recommended that the appliance is installed in a location where the space temperature is 32 °F (0°C) or higher. If the appliance is installed in a location where the ambient temperature is below 32 °F (0°C), the combustion byproducts could condense causing damage to the appli- ance heat exchanger.
This appliance may be common vented with another gas appliance for residential installations as allowed by the codes and standards listed in these instructions.
Non-HUD approved Modular Homes must be vented with an approved roof jack and may not be common vented with other appliances.
VENTING
Category I venting consists of vertically venting one or more appliances in B-vent or masonry chimney (as allowed), using single wall metal pipe or B-vent connectors. Type B-vent system extends in a general vertical direction and does not contain offsets exceeding 45°. A vent system having not more than one 60° offset is permitted.
VENTING INTO AN EXISTING CHIMNEY
For Category I installations, the furnace shall be connected to a factory built chimney or vent complying with a recognized standard, or a masonry or concrete chimney lined with a material acceptable to the authority having jurisdiction. Venting into an unlined masonry chimney or concrete chimney is prohibited.
Where use of an existing chimney is unavoidable, the following rules must be followed:
1.The masonry chimney must be built and installed in accordance with nationally recognized building codes or standards and must be lined with approved fire clay tile flue liners or other approved liner material that will resist corrosion, softening, or cracking from flue gases. THIS FURNACE IS NOT TO BE VENTED INTO AN
UNLINED MASONRY CHIMNEY.
2.This furnace must be vented into a fire clay tile lined masonry chimney only if a source of dilution air is provided, such as by com- mon venting with a draft hood equipped water heater. If no source of dilution air is available, Type B vent must be used, or masonry chimney vent kit 1CK0603 or 1CK0604 must be used. Refer to the instructions with the kit to properly apply these masonry chimney kits.
3.The chimney must extend at least 3 ft (0.91 m) above the highest point where it passes through a roof of a building and at least two feet higher than any portion of the building with a horizontal dis- tance of ten feet.
4.The chimney must extend at least 5 ft (1.5 m) above the highest equipment draft hood or flue collar.
FAN-ASSISTED COMBUSTION SYSTEM
This appliance is equipped with an integral mechanical means to either draw products of combustion through the heat exchanger.
Ambient Combustion Air Supply
This type installation will draw the air required for combustion from within the space surrounding the appliance and from areas or rooms adjacent to the space surrounding the appliance. This may be from within the space in a non-confined location or it may be brought into the furnace area from outdoors through permanent openings or ducts. A single, properly sized pipe from the furnace vent connector to the out- doors must be provided. Combustion air is brought into the furnace through the unit top panel opening.
Combustion Air
FIGURE 23: Combustion Airflow Path Through The Furnace Casing to the Burner Compartment
This type of installation requires that the supply air to the appli- ance(s) be of a sufficient amount to support all of the appliance(s) in the area. Operation of a mechanical exhaust, such as an exhaust fan, kitchen ventilation system, clothes dryer or fireplace may cre- ate conditions requiring special attention to avoid unsatisfactory operation of gas appliances. A venting problem or a lack of supply air will result in a hazardous condition, which can cause the appli- ance to soot and generate dangerous levels of CARBON MONOX- IDE, which can lead to serious injury, property damage and / or death.
An unconfined space is not less than 50 cu.ft (1.42 m3) per 1,000 Btu/ hr (0.2928 kW) input rating for all of the appliances installed in that area.
Rooms communicating directly with the space containing the appli- ances are considered part of the unconfined space, if doors are fur- nished with openings or louvers.
A confined space is an area with less than 50 cu.ft (1.42 m3) per 1,000 Btu/hr (0.2928 kW) input rating for all of the appliances installed in that area. The following must be considered to obtain proper air for combus- tion and ventilation in confined spaces.
Combustion Air Source From Outdoors
The blocking effects of louvers, grilles and screens must be given con- sideration in calculating free area. If the free area of a specific louver or grille is not known, refer to Table 7, to estimate free area.
| Table 7: Estimated Free Area | |
| | |
| Wood or Metal | Wood 20-25%* |
| Louvers or Grilles | Metal 60-70% * |
| | |
| Screens+ | 1/4” (0.635 cm) |
| mesh or larger 100% |
| |
| | |
* Do not use less than 1/4”(0.635 cm) mesh
+Free area of louvers and grille varies widely; the installer should follow louver or grille manufacturer’s instructions.
Dampers, Louvers and Grilles (Canada Only)
1.The free area of a supply air opening shall be calculated by sub- tracting the blockage area of all fixed louvers grilles or screens from the gross area of the opening.
2.Apertures in a fixed louver, a grille, or screen shall have no dimen- sion smaller than 0.25” (0.64 cm).
3.A manually operated damper or manually adjustable louvers are not permitted for use.
4.A automatically operated damper or automatically adjustable lou- vers shall be interlocked so that the main burner cannot operate unless either the damper or the louver is in the fully open position.
