Bakers Pride FC-816 Manual - Manual (Page 16)

VENTILATION OF AN ARCHITECTURALLY ENCLOSED GAS FIRED OVEN
This applies to the FC series ovens initially, but also to FC “stacks” as well as any other enclosed installations. A four
walled “room” around the oven is anticipated, with a ventilation hood as the room’s “ceiling”.
(This four-walled room is selected for this discussion as an easily defined, “worst case” scenario. A more ideal
installation is enclosed on only one, two or three sides, which face the public space of the restaurant. The back and one
or two sides are open to the kitchen and/or other working spaces).
The purpose of ventilation is to remove bi-products of combustion, remove grease laden vapors, limit the temperatures
within the enclosure and to provide fresh air for combustion. The combustion air volume is included in the larger
volume required for temperature controlling the space, therefore only a single calculation is required.
VOLUME REQUIRED (CFM) = RATED INPUT (BTUH) / 105
e.g. The air required for an FC-816 stacked with a Y-800 is 2,476 CFM ( = 260,000 BTUH / 105 ).
This assumes: (1) 70°F air entering the enclosure, (2) the oven runs at an average of 70% of its rated input during peak
business hours and (3) 25% “stack losses” are discharged directly to the top of the enclosure or are removed from the
enclosure by a chimney connection.
At least three total openings must be provided in the enclosure to allow the oven within the enclosure to properly
breathe. Additional openings are acceptable.
At least one opening must be provided. The top opening(s) prevents pressure differences from developing over the
height of the enclosure. Provide an opening of one square inch free area per 1,000 BTUH of Rated Input:
e.g. The top opening for a FC-816 stacked with a Y-800 is 260 sq in (=260,000 BTUH / 1,000).
At least one opening must be provided. The bottom opening(s) provides the bulk of the ventilation air to the space.
Enough area must be provided to limit the entering air velocity to five feet per second. The calculation:
Bottom Opening Free Area (sq in) = Rated Input (BTUH) / 219
e.g. The bottom opening for an FC-816 stacked with a Y-800 is 1,187 sq in (=260,000 BTUH / 219).
The same discussion regarding louvers and grilles applies. The Bottom opening, or openings, should be planned to
distribute air uniformly about the lower portion of the enclosure. The bottom edge of the bottom opening (s) should be
within twelve inches of the floor of the enclosure.
Within the enclosure the normal clearances for safety and service should be maintained. Additionally the floor area of
the enclosure should be at least equal to the “footprint” area of the oven plus the Bottom Opening FreeArea. This limits
the vertical air velocities inside the enclosure to the same five feet per second.
e.g. FC-816 stacked with Y-800......51” deep x 84” wide = 4,284 sq in
Add the bottom free area: 1,187 sq in (Roughly 4 1/2” all around)
Total 5,471 sq in (38 sq ft) [Roughly 60” x 93”]
AIR VOLUME REQUIRED
AIR OPENINGS TO THE ENCLOSURE
TOP OPENING(S)
BOTTOM OPENING(S)
CLEARANCES
Louvers and grilles typically have free area ratings provided by their
manufacturer. If the ratings are not known, assume 25% free area for wood louvers and 60% free area for metal louvers
and grilles.
The top edge of this
opening should be within (12”) twelve inches of the bottom edge of the ventilation hood.
Top Opening FreeArea (sq in) = Rated Input (BTUH) / 1000.
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