Page 19
Exhaust Installation—Multiple Manifold Duct
EXHAUST
INSTALLATION—
MULTIPLE
MANIFOLD DUCT
For Exhaust Duct more than 14 feet (5 m) and 2 elbows
equivalent and more than 0.3 inches ( 8 mm) static pressure.
(See illustration on next page.)
1. Make-up air from outside building may enter enclosure from top or
side walls. (See Dryer Make-Up Air Requirements Chart)
2. Use constant diameter duct with area equal to the sum of dryer
duct areas.
EXAMPLE: 3-12 inch (305 mm) diameter duct = 1-20.78 inch
(528 mm) diameter duct in area. Use 21 inch (534 mm)
diameter duct or diameter to match tube-axial fan.
3. Enclosure (plenum) with service door. This separates the
dryer air from room comfort air.
4. Zero inches clearance to combustible material allowed on
sides and at points within 4 inches (102 mm) of front on top.
5. Heat loss into laundry room from dryer fronts only is about
60 Btu/hr per square foot.
6. Flange mounted, belt driven tube-axial fan. Fan must run
when one or more dryers are running. See suggested
Automatic Electrical Control Wiring Diagram on previous
page. Must meet local electrical codes. Fan air flow (cfm) is
equal to sum of dryer air flows, but static pressure (SP) is
dependent on length of pipe and number of elbows.
7. Barometric Bypass Damper—Adjust to closed flutter
position with all dryers and exhaust fan running. Must be
located within enclosure.
CAUTION: Never install hot water heaters or other gas
appliances in the same room as dryers. Never install cooling
exhaust fans in the same room as dryers.
