Lochinvar CF-CH(E)-i&s-08, 399 Outside Combustion Air - Two Openings, INSTALLATION Continued

Hydronic Heating Boilers and Domestic Water Heaters

INSTALLATION Continued

FIG. 7 Outside Combustion Air - Two Openings

2. Outside Combustion Air, Using Ducts

You can direct outside combustion air to this unit using two air ducts to deliver the air to the boiler room.

Each of the two openings must have a minimum free area of one square inch per 2000 Btu input (11cm2 per kW).

starting on page 22 for specific information regarding this option.

4. Combustion Air from Interior Space

You can direct combustion air to this unit using air from an adjoining interior space. You must provide two openings from the boiler room to the adjoining room.

Each of the two openings must have a net free area of one square inch per 1000 Btu input (22cm2 per kW), but not less than 100 square inches (645cm2).

FIG. 8 Outside Combustion Air Through Ducts

3. Outside Combustion Air - Using Direct Venting

With this option, you can connect combustion air vent piping directly to the unit. See the information under Direct Venting

FIG. 9 Combustion Air from Interior Space

All dimensions are 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 a minimum net free area as specified in TABLE–C, page 14. Single openings shall be installed 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 unit. 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 unit failure.

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