GAYLORD CG Series, Technical Manual

5

INTERNAL FIRE MODE

Automatic internal fire protection is accomplished by the
action of the thermostats, which are located at the point where
the ductwork joins the ventilator.  When the temperature of the
conveying airstream, which must pass over the thermostats,
reaches 350°F (177°C), the system is activated, and the
following occurs:

1.

The hinged, grease-extracting fire damper baffle at the air
inlet of the ventilator closes — stopping the combustion-
supporting, natural draft through the ventilator. (Refer to
Figure 6)

2.

The exhaust fan serving the ventilator is shut off, stopping
the combustion-supporting, mechanically induced draft.
The supply fan is also shut off.

3.

Fire-smothering water spray is released into the interior of
the ventilator through the cleaning system.

4.

The “Fire” light on the Command Center illuminates.

Water will run until the thermostat cools below 350°F (177°C),
and then continue for a 5 minute cool down cycle.  The water
may be shut off prior to the end of the 5 minute cool down cycle
by pushing the “Cancel” button located inside the electrical
compartment of the control cabinet.  After the water has shut
off, the dampers can be reset by pushing the reset handle on
the damper control switch (Refer to Figure 5), and the exhaust
fan(s) re-started by pushing the “Start Fan” button on the
Command Center.

EXTERNAL FIRE MODE

A break glass fire switch is optional (see Figure 4) and if
provided, would normally be located at the exit of the kitchen.
Pulling the fire switch shuts off the supply fan and starts the
exhaust fan if it was off, releases fire smothering water spray
into the interior of the ventilator and the “Fire” light on the
Command Center flashes.  During this time, the fire damper
remains open, and the exhaust fan remains on to help remove
smoke, heat, etc.  If the fire intensified and the thermostat
reached 350°F, the fire damper would then close and the
exhaust fan would shut off.

To resume normal operations, open the fire switch and flip the
toggle switch to the position marked “normal”.  Replace the
glass rod and close the cover.

"CG" SERIES VENTILATOR PRINCIPLE OF OPERATION

TESTING INTERNAL FIRE MODE

The internal fire protection system may be tested periodically
by pushing the “Fire Test Switch” which is located inside the
electrical compartment of the control cabinet.  Pushing this
switch duplicates thermostatic action.  

CAUTION:  Before

pushing the “Fire Test Switch”, check to see if the internal
fire protection system is tied to the building alarm system.

TO RESUME NORMAL OPERATION

1.

To discontinue the 5 minute cool down cycle at any point
during the cycle, push the “Cancel” button located inside
the electrical compartment.

2.

Reset all damper control switches.

3.

Push the “Start Fan” button on the Command Center.

SURFACE FIRE PROTECTION

The Gaylord Ventilator may be equipped with surface fire
protection either dry or wet chemical, or the Gaylord Quencher
System.  In the event of a fire, the surface fire protection
system would normally be activated and discharged prior to
the ventilator’s internal fire protection.  These systems may be
intertied with the ventilator control cabinet to activate the
External Fire Mode.  If the fire is unusually severe or the surface
fire protection system malfunctions, the ventilator’s internal
fire protection system would activate, thus providing a second
level of defense.

FIG.  6

FIRE  CYCLE

FIG.  4

BREAK  GLASS  FIRE  SWITCH

C-1357A  SERIES

FIRE QUENCHING
WATER SPRAY

WATER BARRIER

FIRE DAMPER
BAFFLE IN CLOSED
POSITION

DRAIN LINE

DAMPER CONTROL SWITCH
IS ACTIVATED CLOSING
FIRE DAMPER BAFFLE
AND SHUTTING OFF
EXHAUST FAN

RESET HANDLE

SURFACE FIRE
PROTECTION NOZZLE
(OPTIONAL)

350°F THERMOSTAT

CAUTION:
In case of severe fire and the thermo-
stats located in the duct collar are
activated, and as a precautionary
measure, it is recommended that
the thermostats be replaced.

FIG.  5

DAMPER CONTROL SWITCH

C-61 SERIES