Exhaust and Venting

DRYER AIR FLOW

Nothing is more important than air flow for the proper operation of a clothes

INSTALLATION

dryer. A dryer is a pump which draws make-up air from the out-of-doors,

 

through the heater, through the clothes and then forces the air through the

 

exhaust duct back to the out-of-doors. Just as in a fluid water pump, there must

 

be a fluid air flow to the inlet of the dryer, if there is to be the proper fluid air

 

flow out of the exhaust duct.

 

In summary, there must be the proper size out-of-doors inlet air opening (4-6

 

times the combined areas of the air outlet) and an exhaust duct, size and length

 

of which allows flow through the dryer with no more than 0.3 inches water

 

column static pressure in the exhaust duct.

 

In some instances, special fans are required to supply make-up air, and/or boost

 

exhaust fans are required for both regular and energy saving models.

EXHAUSTING

FOR BEST DRYING:

DUCT

1.

Exhaust duct maximum length 14 feet (4.3 mm) of straight duct and

 

 

maximum of two 90° bends.

 

2.

Use 45° and 30° elbows wherever possible.

 

3.

Exhaust each dryer separately.

 

4.

Use 2 feet (0.6 m) of straight duct on dryer before installing an elbow

 

 

on Energy-Saver models only.

 

5.

Do not install wire mesh or other restrictions in the exhaust duct.

 

6.

Use clean-outs in the exhaust duct and clean periodically when needed.

 

7.

Never exceed 0.3 inches (7.6 mm) water column static pressure in the

 

 

exhaust duct.

 

8.

Inside surface of the duct must be smooth.

 

9.

Recommend pop rivets for duct assembly.

MAKE-UP AIR

FOR BEST DRYING:

 

1.

Provide opening to the out-of-doors in accordance with the following:

 

 

For each dryer—

 

 

6 inches (15 cm) diameter exhaust requires a 1 square feet (0.1 m²)

 

 

opening for make-up air.

 

 

8 inches (20 cm) diameter exhaust requires a 2 square feet (0.2

 

 

m²)opening for make-up air.

 

 

12 inches (30 cm) diameter exhaust requires a 4 square feet (0.4

 

 

m²)opening for make-up air.

 

2.

Use barometric shutters in the inlet air opening to control air when

 

 

dryers are not running.

OTHER

Other Recommendations

RECOMMENDATIONS

To assure compliance, consult local building code requirements.

TROUBLESHOOTING

Troubleshooting

 

Hot dryer surfaces, scorched clothes, slow drying, lint accumulations, or air

 

switch malfunction are indicators of exhaust duct and/or make-up air problems.

 

 

 

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