Measures must be taken to prevent the entry of corrosive chemical fumes to the combustion and ventilation air supply. Such chemicals include, but are not limited to, chlorinated and/or fluorinated hydrocarbons such as found in refrigerants, aerosol propellants,
An adequate supply of air for proper combustion and ventilation must be provided in accordance with Sec.
5.3of the National Fuel Gas Code, ANSI Z223.1. or applicable provisions of the local building codes. Do not obstruct the flow of combustion and ventilation air to the heater.
VENTING
The vent pipe must be the same size or larger than the 4" diameter outlet on the heater. The standard vent outlet is on the right side, but this can be changed to the left side by reversing the orientation of the flue collector box. This can be done easily in the field. Remove the top casing cover to gain access to the flue collector box. Remove the screws along the sides of the flue collector. Disconnect the vent switch tubing from the fitting and remove the fitting from the flue collector box. Lift the box and turn around the other direction. Remove the stainless steel plug button and install the fitting in its place; then install the plug button where the fitting was removed. Reconnect the vent switch tubing to the fitting. Replace and secure the flue collector box with the screws previously removed.
The maximum flue gas temperature at the heater outlet is less than 400 degrees F. Use only the special gas vents listed for use with Category III gas burning heaters, such as the stainless steel
WARNING: Provide a screen or barrier to prevent personal injury in areas where personnel contact with vent pipe can occur; but DO NOT INSULATE the vent pipe, nor use means that will restrict thermal expansion or movement of the vent.
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