GENERAL THEORY OF OPERATION
Figure 1 shows the air distribution and the path of the
flue products in the Vulcan Snorkel™ oven. There are
two tubular sheet metal burners which operate in an
insulated combustion chamber with minimum air
requirements. The flame chamber collects the heat
generated by the burners and directs it through the heat
exchanger tubes which are within the cooking
compartment. The heated flue products are collected in
a box above the oven compartment and directed to the
blower inlet through the Snorkel tube. The oven
compartment is heated indirectly via the heat exchanger
tubes and directly with the flue products drawn into the
oven by the Snorkel tube. A circulating fan also
distributes heat throughout the oven evenly. The two
vents in the top of the oven compartment evacuate
moisture and also vent the oven flue products.
The blower and solenoid operate independently of each
other. The blower operates as long as the doors and
closed or the auxiliary fan switch is actuated. The
solenoid is controlled by the thermostat and the Load
Control. The thermostat must be On and the thermostat
and the load control set to an operating position for the
solenoid to come On and supply heat the oven. Either
the thermostat or load control switch in the "Off" position
will shut off the solenoid.
In order to provide protection against a pilot outage
hazzard, a valve controls the main flow of gas to the
burner. As long as a pilot flame is present, the valve will
remain open. In the absence of pilot heat, the valve
closes, eliminating gas to the burner. Each burner has its
own valve which allows them to operate independently
of each other.
A snap acting door switch, mechanically linked with the
right hand door, shuts off both the heat and the blower
when the door is opened and will automatically reset
when the door is closed.
In ovens equipped with optional auxiliary fan switch, the
door inter-lock can be over-ridden by depressing the
"Auxiliary Fan Switch." The oven over-ride affects the
blower only (not the heat) and is intended for rapid
cooling of the oven interior.
Under "Component Description and Replacement"
section the detailed function of each component is
explained.
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