Cessna 402B 1973 - Page 38

heat registers
is
completely shut off
by
pushing
the
knob
all
the
way
irL
The
knJb
may
be
set
in any
intermediate
position
to regglate
the
quantity
of
air
to
the
cabin.
CABIN
HEAT
REGISTERS
The cabin
heat
registers
are
located
on each side
of tre
passenger
compartment.
Each
register
is
provided
witl
a lever
operated
rotary-
typJvalve
which
controls tlle
amount
of
air coming
from the
heat
regis-
tlrs.
Each
register
is
plainly
marked
for
open or
closed
and may
be
placed
in
any
iatermediate
position
to
reguiate
the
amount of
air
coming
from the
registers.
DEFROST
KNOB
windshield
defrosting
and defogging
is controlled
by
operating
a
push-
pull
type-knob
labeled
DEFROST,.
When
the knob is
pulled
out,
air flows
?rom
ttte
defroster
outlets
at
the
base of
the
vrindshield.
Wben
the
knob
is
pushed
all the
way
in, airflow to
the
defroster outlets
is shut
off.
The
knob
may be
set
in
any
intermediate
position
to
regulate
the
defroster
air-
flow.
HEATER
OVERHEAT
WARNING
TIGHT
An
amber
overheat
warning
light
is
provided
in the
annunciator
panel
and
is labeled
HEATER
OVHT.
When illuminated,
the
light
indicates that
the heatbr overheat
switch
has
been
actuated
and that
the
temperature
of
the
air in the heater
has
exceeded
325'F.
Once
the
heater
overheat
switch
has been
actuated,
the
heater turns
off
and cannot
be
restarted
until
the overheat
switch,
Iocated
in
the
right
forward
nose
compartment
has
been
reset.
Prior to
having the overheat
switch
reset,
the
heater
should be thoroughly
checked to
determine the
reason for
the
malfunction.
HEATER
OPERATION
FOR
HEATING
AND
DEFROSTING
(1)
Battery Switch
-
ON.
(2)
Cabin Air Knobs
-
FuIl
Out.
(3)
Defrost Knob -
Adjust
as desired
(if
defrosting
is
desired).
(4)
Cabin
Heat Knob
-
IVIAX
or
as
desired.
(5)
Cabin Heat Switch -
oN.
(6)
Heat Registers
-
As desired.
2-28