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6.Inadequate air flow...
a.Impellor (blower/fan) "squirrel cage" failure.
b.Loose impellor (blower/fan) "squirrel cage" drive
7.Gas Models
a.Low and/or inconsistent gas pressure;
Natural Gas pressure must be 3.5 inches of water column (8.7 millibars).
Liquid Propane (L.P.) pressure must be 10.5 inches of water column (26.1 millibars).
b.Poor air/gas mixture (too much gas or not enough air) at burner...yellow or poor flame pattern...
1)Not enough
2)Restriction in exhaust.
3)Gas pressure too high.
4)Impellor (blower/fan) "squirrel cage" rotating in the wrong direction.
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 drawer screen is dirty or is not being cleaned often enough.
d..Gas supply may have low heating value.
8.Steam Models
a.Low steam supply...
1)Steam trap too small.
2)Supply line too small.
b.Low steam pressure.
c.Insufficient
d.Lint drawer screen is dirty or is not being cleaned often enough.
e.Restriction in the exhaust.
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