ELECTRIC MODELS

1.Failed oven contactor or coil.

2.Failed electric heating elements. P. Dryer is taking too long to dry.

1.Exhaust duct work too long or is undersized, back pressure cannot exceed .3 inches water column.

2.Restriction in exhaust.

a.Dryer back draft damper is sticking partially closed.

b.Restriction or obstruction in duct work.

1.) Check duct work all the way to the outdoors.

3.Insufficient make up air.

4.Impellor and fan is rotating in the wrong direction only (3 phase models only).

5.Lint screen is dirty or is not being cleaned often enough.

6.Inadequate air flow.

a.Impellor and fan failure.

7.GAS MODELS

a.Low or inconsistent gas pressure.

Natural gas pressure must be between 3.5 and 4 inches of water column. L.P. gas pressure must be between 10.5 and 11 inches of water column.

b.Poor air and gas mixture (too much gas or not enough air) at burner, yellow or poor flame pattern. 1.) Not enough make-up air.

2.) Restriction in exhaust.

3.) Gas pressure too high.

4.) Impellor and fan rotating in the wrong direction (3 phase models).

5.) Burner orifice size (D.M.S.) too large for application (i.e. high elevation).

c.Sail switch is fluttering.

1.) Restriction in exhaust.

a.)) Lint screen is dirty or is not being cleaned often enough. d. Failed burner hi-limit switch, opens at incorrect temperature.

e. Gas supply may have low heating value.

8.ELECTRIC DRYERS

a.Not enough make up air.

b.Restriction in exhaust.

c.Lint screen is dirty or is not being cleaned often enough.

d.Blower and fan is rotating in the wrong direction (3 phase models only).

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American Dryer Corp ML-79 manual Low or inconsistent gas pressure, Electric Dryers