7
-9
2-WAY MULTISET VRF SYSTEM
Trouble Diagnosis
7
F31 Alarm
Alarm code
F31
Alarm meaning
Outdoor unit non-volatile memory (EEPROM) trouble
Alarm conditions
(1) Non-volatile memory is not present when power initialization occurs.
(2) Read values do not match after writing to non-volatile memory is complete.
Probable cause
(1) Memory was not inserted after the PCB was replaced.
(2) The lifetime of the non-volatile memory has been reached.
(3) Non-volatile memory is installed incorrectly (wrong direction, bent pins, etc.).
Check
(1) Check the non-volatile memory on the PCB.
—
—
—
Correction
Example
Notes
1.
2WAY VRF DCI
Alarm Codes
H0
3
alarm
Alarm code
H0
3
Alarm mea
n
i
ng
Compre
ss
or CT
s
e
ns
or di
s
co
nn
ected or
s
hort-circ
u
it
Alarm co
n
ditio
ns
Alarm occ
u
r
s
if the c
u
rre
n
t val
u
e i
s
1.5 A or le
ss
whe
n
2
s
eco
n
d
s
or lo
ng
er have elap
s
ed after
o
u
tp
u
t from that compre
ss
or
s
tarted.
* No c
u
rre
n
t i
s
detected eve
n
tho
ug
h the compre
ss
or i
s
operati
ng
.
Probable ca
us
e
(1) CT circ
u
it fail
u
re (i
n
cl
u
di
ng
c
u
t wiri
ng
, etc.)
(2) Di
s
co
nn
ected CT circ
u
it co
nn
ector
(
3
) Thi
s
CT circ
u
it i
s
co
nn
ected to the co
nn
ector of the other CT circ
u
it.
(4) PCB fail
u
re
(5) Noi
s
e
Check
(1) CT circ
u
it fail
u
re, PCB fail
u
re
Tro
u
ble: • C
u
rre
n
t val
u
e d
u
ri
ng
compre
ss
or operatio
n
i
s
below the thre
s
hold val
u
e.
Check:
• Check that the co
nn
ector i
s
n
ot di
s
co
nn
ected.
• Check the co
n
ti
nu
ity of the CT circ
u
it.
I
ns
tall a
n
ormal CT i
n
place of thi
s
CT a
n
d check. If c
u
rre
n
t i
s
detected, the
n
the
PCB ca
n
be j
u
d
g
ed OK.
CT circ
u
it fail
u
re
• Check that c
u
rre
n
t i
s
flowi
ng
i
n
the pha
s
e where the CT circ
u
it i
s
co
nn
ected.
→
Check volta
g
e a
n
d c
u
rre
n
t.
(2) Cro
ss
ed wiri
ng
or i
ns
tallatio
n
error
Tro
u
ble:
Whe
n
the compre
ss
or i
s
s
topped, the c
u
rre
n
t val
u
e at the other compre
ss
or i
s
hi
g
h.
(
3
) If the ca
us
e i
s
s
till
un
k
n
ow
n
after checki
ng
the above, the
n
it i
s
po
ss
ible that
n
oi
s
e i
s
the
ca
us
e of the tro
u
ble. It i
s
n
ece
ss
ary to co
nn
ect a PC or other i
ns
tr
u
me
n
t.
Correctio
n
(1) Replace the CT circ
u
it.
(2) Replace the o
u
tdoor
un
it PCB.
(
3
) Correct the problem.
Example
(1) The co
nn
ector wa
s
n
ot i
ns
erted after the PCB wa
s
replaced.
Note
s
U
s
e a
n
ormal CT a
s
a tool to determi
n
e whether the tro
u
ble i
s
a PCB fail
u
re or CT fail
u
re.
→
