Piper ARCHER III Pilot Operating Handbook page 311

PA-28.18I.,
ARCHER
III
SECTION
9
SUPPLEMENT
6
3.5
EMERGENCY
PROCEDURES
CHECK LIST (continued)
3.5j
Carburetor Icing
Carburetor Icing
CARB HEAT
MIXTURE.....
...........,....
oN
................Adjust for Maximum
Smoothness
Under certain moist
atmospheric conditions
at
temperatures
of -5"C
to
20"C,it
is possible
for
ice to
form
in the
induction
system. This
is due
to
the
high air velocity
through
the carburetor
venturi
and
the absorption
of
heat
from this air by
vaporization
of
the
fuel. To
avoid this, carburetor
preheat
is
provided to
replace the heat lost by vaporization. Carburetor
heat
should
be
full
on when carburetor ice is
encountered.
REPORT: YB-T;,49
5of22
9-35
ISSUED:
December 22,
2017