Service manual

5-4T-294-01
CONDITION
POSSIBLE CAUSE
REMEDY/
REFERENCE
SECTION
5.11 THERMOSTATIC EXPANSION VALVE MALFUNCTION
Low refrigerant charge 6.5/6.7
External equalizer line plugged Open
W ax, oil or dirt plugging valve or orifice Ice formation at
valve seat
6.25
Low suction pressure with high
s
u
p
e
r
h
e
a
t
Superheat too high 6.5/6.7
superheat
Power assembly failure 6.25
Loss of element/bulb charge 6.25
Broken capillary 6.25
Foreign material in valve 6.25
H
i
h
t
i
i
t
h
l
Superheat setting too low 6.25
High suction pressure with low
s
u
p
e
r
h
e
a
t
External equalizer line plugged Ice holding valve open Open
super
h
ea
t
Foreign material in valve 6.5/6.6
Liquid slugging in compressor
Pin and seat of expansion valve eroded or held open by
foreign material
6.25
F
l
u
c
t
u
a
t
i
n
g
s
u
c
t
i
o
n
p
r
e
s
s
u
r
e
Improper bulb location or installation 6.25
F
l
uctuat
i
ng suct
i
on pressure
Low superheat setting 6.25
5.12 POWER AUTOTRANSFORMER MALFUNCTION
Circuit breaker (CB-1 or CB-2) tripped Check
U
n
i
t
w
i
l
l
n
o
t
s
t
a
r
t
Power transformer (TRANS) defective 6.21
U
n
i
tw
i
l
l
not start
Power source not turned ON Check
460 VAC power plug is not inserted into the receptacle 2.4
5.13 WATER-COOLED CONDENSER OR WATER PRESSURE SWITCH
H
i
g
h
d
i
s
c
h
a
r
g
e
p
r
e
s
s
u
r
e
Dirty coil 6.28
H
i
g
h
d
i
sc
h
arge pressure
Noncondensibles 6.28
C
o
n
d
e
n
s
e
r
f
a
n
s
t
a
r
t
s
a
n
d
s
t
o
p
s
Water pressure switch (WP) malfunction Check
C
on
d
enser
f
an starts an
d
stops
W ater supply interruption Check