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When a vent is less than 10 feet high, the vent should be at least as large as the flue collar outlet.b) Vents for draft hoods or flue collars 12 inches in diameter or less should NOT be reduced more than one pipe size.
Larger pipe sizes and fittings are available upon request. All spiral pipe is SMACNA 24-26 gauge. Heavier gauge pipe is available. All elbows are smooth bore, long radius (1.5 x clr) 18 gauge and 20 gauge welded air tight.All elbows and fittings have male ends to fit inside spiral pipe.To attach two male ends, it is suggested to cut a small section (4 long) of spiral pipe to make an outer sleeve. Please Note: In order to ship pipe and sheet metal fittings correctly, a suitable box must be used.ll elbows and fittings have male ends to fit inside spiral pipe. To attach two male ends, it is suggested to cut a small section (4 long) of spiral pipe to make an outer sleeve. Please Note: In order to ship pipe and sheet metal fittings correctly, a suitable box must be used.