Multiple Dryer Common Venting, ADH-120 | American Dryer Corp ADH-75

Multiple Dryer (Common) Venting

Important

!For extended ductwork runs, the cross section area of the ductwork can only be increased to an extent.

When the ductwork approaches the maximum limits as noted in this manual, a professional HVAC firm should be consulted for proper venting information.

If it is not feasible to provide separate exhaust ducts for each dryer, ducts from individual dryers may be channeled into a “common main duct.” The individual ducts should enter the bottom or side of the main duct at an angle not more than 45º in the direction of airflow. The main duct should be tapered, with the diameter increasing before each individual duct is added. The minimum diameter of the individual ductwork must be at least Dimension A (12-inches [30.48 cm] for the ADH-75; 18-inches [45.72 cm] for the ADH-120; 20-inches [50.8 cm] for the ADH-170).

The illustration on the right shows the minimum cross- sectional area for multiple dryer round or square venting. These figures must be increased if the main duct run from the last dryer to where it exhausts to the outdoors is longer than Dimension B (20 feet [6.096 meters]) or has more than 1 elbow in it.

ADH-75

Multiple Dryer Venting with 12-Inch (30.48 cm) Diameter

1,200 cfm (33.98 cmm) Exhaust Connections at Common Duct

NUMBER OF DRYERS		4	3	2	1
MINIMUM CROSS-	SQ IN	315	254	200	115
SECTIONAL AREA	SQ CM	2032	1638	1290	729
MINIMUM ROUND	IN	20	18	16	12
DUCT DIAMETER	CM	51	46	41	30

ADH-120

Multiple Dryer Venting with 18-Inch (45.72 cm) Diameter

2,500 cfm (70.79 cmm) Exhaust Connections at Common Duct

NUMBER OF DRYERS		4	3	2	1
MINIMUM CROSS-	SQ IN	455	380	255	115
SECTIONAL AREA	SQ CM	2935	2452	1645	742
MINIMUM ROUND	IN	24	22	20	18
DUCT DIAMETER	CM	61	56	51	46

Important

!ADH-75 and ADH-120: No more than 4 dryers should be connected to 1 main common duct.

ADH-170

Multiple Dryer Venting with 20-Inch (50.8 cm) Diameter

4,400 cfm (124.59 cmm) Exhaust Connections at Common Duct

NUMBER OF DRYERS		3	2	1
MINIMUM CROSS-	SQ IN	707	531	315
SECTIONAL AREA	SQ CM	4561	3426	2032
MINIMUM ROUND	IN	30	26	20
DUCT DIAMETER	CM	76	66	51

Important

!ADH-170: No more than 3 dryers should be connected to 1 main common duct.

NOTE 1 Opening must be 2-inches (5.08 cm) larger than the duct (all the way around). The duct must be centered within this opening.

NOTE 2 Distance should be 2 times the diameter of the duct to the nearest obstruction.

NOTES ______________________________________________________

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American Dryer Corp.

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