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7
3
8
Q
R
F
S
CHEM
A
T
IC
LE
G
E
ND
NO
TE
S
:
1.
Compr
essor
and
fa
n
m
ot
ors
are
ther
m
a
lly
p
ro
te
ct
ed.
2.
W
ir
e
in
acc
ordance
wit
h
N
at
ional
E
lect
ri
c
a
l
Cod
e
(N
EC)
and
local
codes
.
R
eplace
an
y
or
iginal
wires
with
9
0°
C
wire
or
its
equi
v
a
lent.
3.
Use
minimum
60°
C
wire
fo
r
field
po
wer
wir
ing.
4.
T
ransf
or
mer
fac
to
ry
wired
fo
r
230
v.
F
o
r
2
0
8
v
m
o
v
e
b
lue
wire
to
208
v
o
lt
ta
p
.
5.
Cr
ank
case
heater
an
d
ther
mostat
used
on
selected
m
odels
onl
y.
NO
T
E
:
A
ll
ther
m
ist
o
rs
a
re
identical.
THE
RM
IS
T
O
R
E
Q
UIV
ALE
NCE
T
e
mp
eratu
re
Resi
stan
ce
FC
95
35
6,500
72
22
11,400
32
0
32,500
C—
Cont
ac
to
r,
Com
press
or
CAP
—
Capacit
or
CCHT
—
Cr
ank
case
Heater
T
her
m
o
st
a
t
CH
—
Cr
ank
case
Heat
er
COMP
—
Compr
essor
Mo
to
r
DF
T
—
Def
rost
T
her
most
at
EQU
IP
—
Equipm
ent
GN
D
—
G
round
HP
S
—
High-Pre
ssure
Sw
it
ch
LL
P
S
—
Li
q
u
id
Lo
w
P
res
sure
Swit
ch
OD
A
—
O
u
tdoor
Air
T
emperat
ur
e
OF
M
—
O
u
tdoor
F
a
n
M
otor
OF
R
—
O
u
tdoor
F
a
n
R
ela
y
OL
—
O
v
er
load
RV
S
—
Re
v
e
rsing
V
alv
e
S
olenoi
d
TB
—
T
e
rm
inal
Boa
rd
TH
—
T
her
m
ist
or
T
RAN
—
T
ransf
or
mer
Splice
(F
ield)
T
e
rm
in
al
(M
ar
k
ed)
T
e
rm
in
al
(Unm
ar
k
ed)
T
e
rm
in
al
Bloc
k
S
p
lice
F
a
ctor
y
W
ir
ing
F
ield
C
ont
rol
W
ir
ing
F
ield
P
o
w
e
r
W
ir
in
g
3
8
QRF
OPERA
TION
SEQ
U
E
N
C
E
C
A
L
L
F
O
R
C
OOL
IN
G:
1.
Con
trol
v
olt
age
fr
om
tr
ans
fo
rm
e
r
to
m
icroproc
essor
c
ont
rol
in
indoor
unit
(24
v
).
2.
A
t
micr
oproces
sor
cont
rol
24
v
is
s
wi
tched
to
“G
,”
“O
,”
and
“Y
.”
3.
24
v
from
micropr
ocess
or
cont
ro
l
“G
”
energiz
e
s
fa
n
rela
y
a
t
out
door
u
n
it
a
n
d
out
door-f
an
mot
o
r
runs
.
4.
24
v
from
microp
rocess
or
c
ont
rol
“O
”
energizes
R
V
S
a
t
out
door
unit
through
“O
”
o
n
out
door
uni
t
te
rm
inal
board.
5.
24
v
fr
o
m
the
m
icroproc
essor
cont
rol
“Y
”
energ
izes
th
e
cont
act
or
c
oil
in
th
e
o
ut
door
unit
.
T
he
com
-
pr
es
s
o
r
will
run.
6.
If
the
HP
S
,
inter
nal
pr
ot
ec
to
r
o
f
the
com
pressor
,
o
r
LLP
S
open,
th
e
2
4
v
to
th
e
c
ont
ac
to
r
will
be
interr
upted.
T
h
e
c
ompres
sor
and
out
door
fa
n
m
ot
or
will
stop
.
C
A
L
L
FO
R
H
EA
TI
N
G
:
1.
Con
trol
v
olt
age
fr
om
tr
ans
fo
rm
e
r
to
m
icroproc
essor
c
ont
rol
in
indoor
unit
(24
v
).
2.
A
t
micr
oproces
sor
cont
rol
24
v
is
s
wi
tched
to
“G
,”
“Y
,”
and
“R
.”
3.
24
v
from
m
ic
roproc
essor
co
nt
rol
“G
”
energiz
es
fa
n
rela
y
a
t
out
door
unit
and
out
door
fa
n
m
ot
or
runs
.
4.
24
v
fro
m
m
icropr
ocess
or
c
ont
ro
l
“Y
”
ener
gi
zes
th
e
contactor
c
oil
and
th
e
c
om
presso
r
will
ru
n
.
5.
Dem
and
def
ro
st
is
c
ont
ro
lled
b
y
th
e
indo
or
unit
m
icroproc
essor
con
trol.
6.
T
h
e
indoo
r
unit
mic
roproces
sor
cont
rol
cont
in
uous
ly
m
onit
ors
bot
h
out
door
c
o
il
te
m
perat
ure
and
ou
tdoor
ambient
te
mperat
ure,
det
er
mining
th
e
opt
imum
def
ros
t
lengt
h
and
in
te
rv
al
fo
r
e
xist
ing
out
-
do
or
c
ondit
ions
.
D
E
FR
OST
M
ODE:
1.
M
icroproc
essor
c
ont
rol
s
wit
c
hes
24
v
to
“O
”
and
energiz
es
R
V
S
.
2.
M
icroproc
essor
co
nt
rol
s
wit
c
hes
24
v
from
out
doo
r
fan
re
la
y,
deenerg
ized
rela
y
s
tops
out
d
oor
fa
n
m
o
to
r
operat
ion.
3.
M
icroproc
essor
control
will
te
rm
inat
e
def
ro
st
when
outdoor
c
o
il
sensor
reach
es
64.4
F
o
r
a
fter
10
m
inut
es
of
def
rost
oper
at
ion.
Unit
then
s
wit
ches
bac
k
to
nor
mal
heat
ing
mode
.
4.
Dur
in
g
heat
ing
or
def
rost
,
if
the
HPS,
int
er
nal
prot
ec
to
r
o
f
the
c
o
mpr
essor
,
o
r
LLP
S
open,
th
e
2
4
v
to
th
e
c
ont
act
o
r
c
o
il
wil
l
b
e
int
err
upt
ed,
th
e
c
om
pres
sor
and
out
door
fa
n
m
ot
or
wil
l
s
to
p
.
A08238
Fig. 7 -- 38QRF018--060 Typical Wiring Schematic
38Q
RF