4
Dynaflow MJ hood
Principle of Operation
The MJ Perimeter Defense design exhaust volume is based on the appliances under the hood. It’s a simple calculation to
determine your best exhaust volume for any commercial kitchen lineup. The MJ Perimeter Defense hood can be fine-tuned
to provide excellent smoke capture with maximum grease extraction. A MJ tangential blower is mounted on top of the
plenum. Return air from the ceiling is drawn into the blower inlet through removable washable aluminum mesh filters.
The tangential MJ blower discharges air through a fusible link fire damper into the MJ plenum. The air is then discharged
from the bottom through a two way adjustable perforated grill. The air is then proportioned between the appliances and the
chef aria by adjusting the comfort tuning dial. This is not fresh air from outside the building. Fresh supply air must still be
introduced somewhere else in the commercial kitchen.
INTERNAL APPLIANCE DISCHARGE
HOOD CANOPY
END VIEW
MESH FILTERS
RHEOSTAT
SIDEFLOW DISCHARGE
HOOD CANOPY
FRONT RIGHT VIEW
S/S PERFORATED
DISCHARGE
FRONTFLOW
MJ PLENUM
FIRE DAMPER
MJ BLOWER
MESH FILTERS
RHEOSTAT
S/S PERFORATED
DISCHARGE
SIDEFLOW
MJ PLENUM
FIRE DAMPER
MJ BLOWER
Introducing supply air back into the kitchen is good engineering practice. An adequate supply of fresh air eliminates cold
drafts, and hot spots, enhances the capture capability of the hood and results in a more comfortable kitchen environment. A
supply air volume of at least 80% of the total exhaust is recommended. The fresh air should be tempered to between 55 and
75F (13 to 24C). Direct the fresh air to separate diffusers surrounding the hood located in the finished ceiling. The diffusers
must be located to eliminate short circuiting the exhaust and drafting. Consult with factory for recommended kitchen
diffuser locations. If the hood is required to supply the fresh air directly refer to the Spring Air
MB DYNAFLOW
specification sheet
APPLIANCE
6.63
5.25
2.25
4.63
6.00
10.00
3.00
47.00
5.25
3.00
87.00
23.00
4.63
Dynaflow FN-B-MJ Hood Section View with standard VE filters.
Figure 5
MJ Perimeter Defense Operation
Figure 4
Summary of Contents for Dynaflow
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