In areas where the ambient temperature
can fall below –20 deg. F, it is
recommended that a low temperature
limit control (freeze thermostat ) be
installed (not provided by Garmat
USA®. The low temperature control
shall be installed in series with the high
limit switch in the gas train safety
circuit.
High Gas Pressure Switch
( Models 99273 and 99275 )
This component is on the gas manifold
and will disconnect electrical power to
the gas train circuit before reaching the
flame guard device. In the event that
more than 21” WC of gas pressure enters
the gas manifold at this point, the switch
will disconnect the power and will need
to be manually reset.
Low Gas Pressure Switch
( Models 99273 and 99275 )
This component is on the gas manifold
and will disconnect electrical power to
the gas train circuit before reaching the
flame guard device. In the event that less
than 3” WC of gas pressure enters the
gas manifold or pressure drops below
this point, the switch will disconnect the
power and will automatically reset when
pressure is restored.`
Proof Of Closure Switch
( Models 99273 and 99275 )
This switch is mounted directly under
one of the blocking valves on the gas
train and is linked to the valve actuator
and proves that the valve is closed
before allowing electrical power to
continue through the gas train circuit.
Cabin Pressure Control System
( Model 99270 )
A manual ¼ adjust lever is provided at
the exhaust pressure damper. A slack
tube manometer is provided for
montering the cabin pressure.
( Models 99273 and 99275 )
The remote control panel contains a
photohelic gauge. This gauge is
displayed on the face of the remote panel
and controls the air pressure within the
cabin. This gauge is adjustable using the
two orange needles visible on the face of
the gauge. The gauge operates a
modulating motor attached to exhaust
pressure damper. Opening the cabin will
cause loss of cabin air pressure.
PROGRAMMABLE LOGIC
CONTROLLER ( PLC )
( All Models)
The electrical panel contains a
programmable logic controller ( PLC ).
The PLC controls all of the automatic
functions of the control sequence
including flash-off time duration, bake
time duration and cool down time
duration. Bake time duration is set at the
remote panel on the 99270 deluxe,
99273, 99275 models. On the model
99270 the bake timer is internal in the
PLC. Flash-off time duration and cool
down time duration are internal
functions of the PLC and are set at the
factory. The factory setting of the flash-
off time duration is three minutes and for
the cool down time duration is ten
minutes. These time durations can be
reset by your authorized local authorized
distributor.
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Summary of Contents for 99270
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