J&R MANUFACTURING 250R-FS, Operation And Service Manual

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DESIGN
T
EMPERATURE
C
ONTROL
:
A thermostat activates and controls the combustion air supply to the
firebox and the exhaust from the pit through the flue damper. If the unit
is equipped with an electrical heating element, the thermostat also
controls it.
H
EAT
F
LOW
:
Heat and smoke flow through refractory lined flues into the cooking
chamber and are circulated by a convection fan system.
E
VACUATION
S
YSTEM
:
Turning the EVAC switch on opens a damper to directly vent the
firebox, opens exit dampers from the oven, and opens a fresh air supply
damper at the top of the oven as the smoke is evacuated from the
cooking chamber into the stack. Evacuation should be in 45 seconds to
2 minutes, depending on the net draft at the chimney connector (this
depends on the air balance in the building).
EVAC
OR
S
TACK
F
AN
:
A jet blower fan maintains a draft in the stack and pulls fresh
ambient air into the stack to mix with the exhaust from the pit.
H
IGH
-L
IMIT
P
ROTECTION
:
All dampers are closed and fans (except the cabinet cooling fans) are
shut off if the temperature in the cooking chamber reaches 450° (reset is
automatic upon cool down).
P
OWER
I
NTERRUPTION
P
ROTECTION
:
Upon loss of power, all dampers close and the temperature will begin
to drop.
G
REASE
H
ANDLING
:
Grease is held in the sump in the bottom (coolest) part of the oven
and is drained by opening a valve located behind an access door adjacent
to the firebox.
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