49
VENT PIPE SIZING AND MAXIMUM VENT LENGTHS (cont.)
GENERAL VENTING REQUIREMENTS AND
GUIDELINES
Venting
* This is the recommended maximum number of long sweep elbows for either 2 or 3 inch pipe. Combinaons
of long sweep 90s, standard 90s, or 45s may be used, but the manufacturer recommends the use of long
sweep 90s whenever possible because the use of the maximum number of standard 90 and 45 elbows
only may result in nuisance furnace outages due to individual installaon specifics.
Exceeding the recommended maximum number of elbows may cause nuisance operaon of the pressure switch.