Raytheon Beech Baron E55 - Page 105

RaVNmee
nireraft
Company
BARON
55
AND
58
SHOP
MANUAL
SERVICING
AIR
CONDITIONING
SYSTEM
(TE-1
1
19,
TE-
1
125
AND
AFTER; TH-873,
TH-895
AND
AFTER)
I
NOTE:
The
original
air
conditioning
installation
for
airplanes
TE-1119,
TE-1125
and
After,
and
TH-873,
TH-895
thru
TH-1744
use
R-12
refrigerant,
while
TH-1745
and
After
use
R-134a
refrigerant.
Servicing
the air
conditioning
system
consist
of
periodically
checking
the
refrigerant
level and
changing
the
system
air
filters
(both
forward and
aft
evaporator
filters). Recharge
the
system
whenever the
refrigerant
level is
low,
air has
entered
the
system
or
components
carrying
refrigerant
are
replaced. Refrigerant
leaks
may
be detected
by
inspection
with
a
flameless
leak
detector.
NOTE:
If
the
flared
freon
lines
on
the
air
conditioning
system
are
removed,
new
Seco
7A
washers
of the
proper
size
should
be
used when
reinstalling
the
lines
to
ensure
a
good
seal.
CHARGING
THE
AIR
CONDITIONING
SYSTEM
WARNING:
A
face
shield
should
be
worn
when
servicing
the
lines;
refrigerant,
coming
in contact
with the
eyes,
can cause
the
loss
of
sight.
The
system
should
be
recharged
when:
a.
The
refrigerant
level
is
insufficient
or
the
refrigerant
observed
through
the
sight
glass
in
the
receiver-dryer
contains
bubbles
or
appears
milky.
b.
Leaks
have been
detected
in
system.
c.
Airhas
enteredthesystem.
d.
Components
carrying
refrigerant
have
been
replaced.
Hook
the
recycle/recovery servicing
unit
to
the
connections
located under the
copilot’s
seat.
WARNING:
Due
to
air
quality
control
regulations being
enacted
in
the
United
States,
R-12
and R-134a
refrigerant
cannot
be vented
into
the
atmosphere.
When
performing
maintenance
on
the
vapor
cycle
system
where
refrigerant
R-12
or
R-134a
can
escape
from
the
system,
evacuate
the
system
with
a
recovery
or
recycle
servicing
unit
that
will
salvage
the
refrigerant.
NOTE:
To
prevent
possible damage
to
the
compressor,
refrigerant
is
to
be
added
to
the
system
in
the
vapor
form
to
prevent
liquid
slugging.
The
compressor
does
not
have
to
be
run
during
the
charging
cycle.
I
Charge
a
completely purged
system
with
3
pounds
of
R-12
or
R-134a
refrigerant
(34
or
68,
Chart
3).
On
TE-1119,
TE-1125
and
After,
and
TH-873,
TH-895
thru
TH-1744
use
R-12
refrigerant.
On
TH-1745
and After
use
R-134a
refrigerant.
When
charging
the
system,
observe the
sight
glass
for bubbles
or a
milky
appearance
caused
by
an
insufficient
refrigerant
level.
On
a
fully
charged
system
the
sight
glass
should
be
clear
in
an
ambient
temperature
of
75"
F
or
above.
If
it
is
necessary
to
add
refrigerant
to
a
partially
charged
system,
add
refrigerant slowly
until the
bubbles
disappear
as
observed
through
the
sight glass,
then
add
an
additional
2
ounces
of
refrigerant.
EXPANSION
VALVES
Even
though
the
expansion
valves
are
of the
adjustable
type,
it
is
impossible
to
properly
adjust
them
on
the
airplane.
The
expansion
valves
are
adjusted
at
the
factory
to
38
0.5
psi,
but without
proper
equipment,
a
satisfactory
adjustment
can
not
be achieved.
If
the valves
are
not
operating
properly,
replace
the valves with
new
ones.
Page
20~3:lb,
SECTION
2
E23