Carrier SUPRA 850Mt - No Evaporator Air Flow Restricted Air Flow

5
-
6
6
2
-
-
6
1
1
X
X
-
-
2
0
(
0
3
/
0
4
)
I
N
D
I
C
A
T
I
O
N
/
T
R
O
U
B
L
E
P
O
S
S
I
B
L
E
C
A
U
S
E
S
 REFERENCE
SECTION
5.3
.9
No
eva
pora
tor
air
flow
res
tri
cte
d
air
flow
E
v
a
p
o
r
a
t
o
r
c
o
i
l
b
l
o
c
k
e
d
F
r
o
s
t
o
n
c
o
i
l
Dirty coil
Fan
motor(sà malfunctio
n
Check
4.16.1
No
or
par
tial
eva
pora
tor
air
flo
w
V-
bel
t b
rok
en
or
loo
se
Clutch defective
Evaporator fan loose or defective
Evapo
rator
fan
rotating backwards
Evaporator air flow blocked in trailer (box)
Fan
motor(s) malfunction
4.4
Replace
Check
4.4
Check
5.3
.10
Expa
nsio
n
val
ve
mal
func
tion
Low suction pressure with high
superheat
Low refrigerant charge
External equalizer line plugged
Ice formation at valve seat
Wax, oil or dirt plugging valve or orifice
Broken capillary
Power assembly failure or
partial
Loss of element/bulb charge
Superh
eat setting
too high
4.6 / 4.8
Clean
4.7
4.18
4.18
Replace
Replace
4.18
Low superheat and liquid slugging
in compressor
Superheat setting too low
External equalizer line plugged
Ice holding valve open
Foreig
n
materia
l
in valve
Pin and seat of expansion valve eroded or held open by
foreign material
4.18
Open
4.7
Clean
4.18
Fluc
tuat
ing
suc
tion
pre
ssu
re
Imp
rope
r
bul
b
loc
atio
n
or
ins
tall
atio
n
Low superheat setting
4.18
4.18
H
i
g
h
s
u
p
e
r
h
e
a
t
B
r
o
k
e
n
c
a
p
i
l
l
a
r
y
4
.
1
8
5.3
.1
1
Hot
gas
val
ve
mal
func
tion
V
alv
e do
es n
ot fu
ncti
on p
rope
rly
No p
owe
r to
val
ve
Improper wiring or loose connections
Coil defective
Valve improperly assembled
Coil or coil sleeve improperly assembled
Temperature controller malfunction
Movement of plunger restricted due to:
a. Corroded or worn parts
b. Foreign material lodged in valve
c. Bent or dented enclosing tube
Check
Check
2.9.2
2.9.2
2.9.2
Replace
2.9.2
Valve shifts but refrigerant
continues to flow
Foreign material lodged under seat
Defective seat
2.9.2
2.9.2