Blodgett 1048 - Manual (Page 10)

8
Installation
Ventilation
DIRECT FLUE ARRANGEMENT
When the installation of a mechanically driven exhaust
hood is impractical the oven may be vented by a direct
flue arrangement.
WARNING!!
It is essential that the direct flue be installed
as follows. Incorrect installation will result in
unsatisfactory baking and oven damage.
The flue must be class B or better with a diameter of 10”
(25.4 cm). The height of the flue should rise 6-8 ft (2-2.5
m) above the roof of the building or any proximate struc-
ture. Never direct vent the oven into a hood. The flue
should be capped with a UL Listed type vent cap to isolate
the unit from external environmental conditions.
The direct vent cannot replace air consumed and vented
by the oven. Provisions must be made to supply the room
with sufficient make-up air. Total make-up air require-
ments for each oven section should be approximately 30
CFM per section. To increase the supply air entering the
room, a ventilation expert should be consulted.
Installing the draft hood
Ovens ordered for direct venting are supplied with a draft
hood. Install the draft hood as follows:
1. Place the draft hood over the flue connector.
2. Secure both ends with the sheet metal screws pro-
vided.
Draft Hood
Flue
Front of Oven
Figure 6
VENTING PROBLEMS
Blodgett gas deck ovens use the natural principal of heat
rising as the basic method of ventilation. If the venting of
any deck oven is either restricted or forced in any way
the baking characteristics of the oven will be adversely
affected.
Examples of forced venting include:
• installation of a fan in a direct vent pipe
• use of a canopy type hood without the draft diverter
Examples of restricted venting include:
• use of tees and elbows
• long horizontal runs
Insufficient make-up air can cause heated air and com-
bustibles to remain in the oven shortening the life of the
components.