Carrier 40MBQB09D-3 Service Manual

59
P3 (Current protection of compressor) error diagnosis and
solution.
Error Code P3
Malfunction decision conditions If the outdoor current exceeds the current limit value, the LED displays the failure.
Supposed causes
S Wiring mistake
S Over load protector faulty
S System block
S Outdoor PCB faulty
Troubleshooting
f
compresso
r
J
u
d
ge
1
:
C
h
ec
k
w
h
et
h
er t
h
e input
current o
f
the power supply wire
is more t
h
an 1
2
.
5
A
(
1
8
K
)
(
F
or
27
K
,
i
t
i
s
17
.
F
or
30
K
,
i
t
i
s1
8
.
5
.
F
or
36
K
,
i
t
i
s
2
3
A
)
Judge 1: Check whether the input
current of the power supply wire
is more than 12.5A(18K) (For
27K, it is 17.For 30K, it is 18.5.For
36K, it is 23A)
Yes
Rep
l
ace t
h
e e
l
ectric contro
l
b
ox
Replace the electric control box
C
h
ec
k
w
h
et
h
er t
h
e
re
f
rigerant system
is o
k
Check whether the
refrigerant system
is ok
Ju
d
ge
2
:
C
h
ec
k
w
h
et
h
er t
h
e
outdoor am
b
ient temperature
is
h
ig
h
er t
h
an 5
0
Judge 2: Check whether the
outdoor ambient temperature
is higher than 122 °F
No
S
top t
h
e unit
Stop the unitYes
Ju
d
ge
3
:
C
h
ec
k
w
h
et
h
er t
h
e
outdoor unit is
b
ad ve
l
a o
n
Judge 3: Check whether the
No
M
a
k
e t
h l
ate we
ll
Yes
J
u
d
ge
5
:
The re
f
rigerant pipe is
bl
oc
k
ed
Judge 5: The refrigerant pipe is
blocked
No
Let the re
f
rigerant ou
t
,
t
h
en use t
h
e
h
ig
h
pressure
nitrogen or re
f
rigerant to blow pip
e
,
vacuum
i
ze
a
nd charge the re
f
rigerant again
Let the refrigerant out, then use the high pressure
nitrogen or refrigerant to blow pipe, vacuumize
and charge the refrigerant again
Yes
J
u
d
ge
4
:
Ch
ec
k
w
h
et
h
er t
h
e
h
eat exc
h
anger is dirty
Judge 4: Check whether the
heat exchanger is dirty
No
C
l
ean t
h
e
h
eat exc
h
anger
Clean the heat exchangerYes
Yes
Rep
l
ace outdoor main
b
oard
,
a
nd c
h
ec
k
w
h
et
h
er t
h
e
s
ystem can run norma
lly
Replace outdoor main
board,and check whether the
system can run normally
No
Yes
Trou
bl
e is so
l
ved
Trouble is solved
R
eplace outdoor main boar
d
Replace outdoor main board
No

Carrier 40MBQB09D-3 Specifications

General

Brand	Carrier
Model	40MBQB09D-3
Category	Air Conditioner
Language	English