Carrier 40MAQB09B--3 - Condenser High Temperature Protection Diagnosis (P5)

62
P5 (High temperature protection of condenser) error diagnosis and
solution
Error Code P5
Malfunction decision conditions When outdoor pipe temperature is more than 149°F, the unit stops, and unit runs again when the
outdoor pipe temperature is less than 125°F.
Supposed causes
S The condenser temperature sensor faulty
S Heat exchanger dirty
S System block
Troubleshooting
H
i
g
h tem
p
erature
p
rotecon o
f
con
d
ense
r
High temperature protecon of
condenser
C
heck whether the
c
on
d
enser temperature
i
s
High
er
th
an
6
5
°C
Check whether the
condenser temperature is
Higher than
149
°F
Yes
Check whether the
resistance o
f
condenser
tem
p
.
sensor
i
s
n
orma
l
refer to the
Appendix
1
Check whether the
re
1
Check whether the
resistance of condenser
temp. sensor is normal
refer to the Appendix 1
R
epl
ace t
h
e tem
p
erature sensor
Replace the temperature sensor
No
No
C
heck whether the outdoo
r
am
b
i
ent tem
p
erature
i
s
high
er t
h
an
50
Check whether the outdoor
ambient temperature is
higher than 122 °F
No
Stop t
h
e uni
t
Stop the unit Yes
C
heck i
f
the outdoor unit
ven
l
aon is good
Check if the outdoor unit
venlaon is good
Yes
M
ak
e t
h
e out
d
oor un
i
t vent
il
ate we
ll
Make the outdoor unit ventilate well
C
heck whether the heat
e
xc
h
anger
i
s
di
rt
y
Check whether the heat
exchanger is dirty
No
C
lean the heat exchanger
Clean the heat exchangerYes
C
heck whether the re
f
ri
g
erant
sy
stem
i
s o
k
Check whether the refrigerant
system is ok
R
ep
l
ace out
d
oor ma
i
n
b
oar
d
Replace outdoor main
board
No
R
ef
ri
g
erant is not enou
g
h add the
r
e
f
rigerant
Refrigerant is not enough add the
refrigerant
No
C
heck i
f
the outdoor
f
an runs
p
ro
p
er
ly
Check if the outdoor fan runs
properly
please re
f
er to the soluon o
f
f
an
s
peed has been out o
f
control
mal
f
uncon
.
F
ind out t
h
e cause and
h
ave it so
l
ve
d
.
please refer to the soluon of fan
speed has been out of control
malfuncon . Find out the cause and
have it solved.
No
Yes
No
C
orrect t
h
e connecon
Correct the conneconNo
Yes
C
heck the connecon
b
etween temperature
s
ensor an
d
P
C
B
.
Check the connecon
between temperature
sensor and PCB.
Yes