Why Is My Hood Leaking Grease?

  Grease Filter Picture – Notice the Grease Drain Holes
                      They must face forward!

Why is my hood leaking grease?  Here are some possibilities

1.  Your fan may be turning too fast. There is an optimum air velocity for removing grease laden air from a kitchen grease exhaust system.
 The ASHRAE research report RP-1033 shows that air movement a 500 fpm is more efficient and preferable to 1,000 fpm, 1,500 fpm, and 2,000 fpm for removal of grease laden air from the sides of duct work.  If your fan is turning too fast the grease is building up on the walls of the duct and not being exhausted.
     A.  Fans turn too fast when the pullies are the wrong size.
     B.  Motors come in 2 speeds, 1725 RPM and 3450 RPM.  Make sure you have the right motor and that it is wired correctly.
2.  You may have your filters in backwards.  Be sure the grease drain holes are facing forward.
3.  Filters must be installed vertically at a 45 degree angle to work properly.
4.  You may have a broken or loose fan belt.
5.  Your fan may not be working.
     A.  Is the fan switch in the “on” position?
     B.  Is the electrical circuit breaker tripped?
     C.  The electrical motor could be bad.
     D.  There could be an electrical short or bad ground wire.
     E.  The bearings may be frozen on the fan in the motor compartment.
6.  Your grease tray or grease cup may need cleaning.
7.  Your kitchen grease exhaust system needs cleaning.