Navien NP-180, Service Manual

Page: 103 / 179

©N
avien
Am
eri
c
a
I
n
c
. 20
1
0
NR/NP
series servi
c
e Manua
l
1
0
1
Versi
o
n 2.0
Check method Error
Heat e
xch
an
g
er
o
ver
-h
eate
d
O
t
h
er tr
o
u
bl
e
D
e
f
e
c
tive
h
eat
e
xch
an
g
er
D
e
f
e
c
tive
o
ver
h
eat
PCB
D
e
f
e
c
tive
PCB
< Ch
e
c
k t
h
e
o
ver
h
eat
co
ntr
oll
er
>
1
.
Th
e err
o
r
occ
urs
d
ue t
o h
i
gh
e
xh
aust
g
as te
mp
erature
c
ause
d by
t
h
e
d
e
f
e
c
tive
h
eat e
xch
an
g
er.
2.
Th
e err
o
r
occ
urs
d
ue t
o h
i
gh
te
mp
erature
d
ue t
o
t
h
e
h
eat
l
eake
d
f
r
om
t
h
e
h
eat e
xch
an
g
er.
3
.
R
e
pl
a
c
e t
h
e
h
eat e
xch
an
g
er.
D
e
f
e
c
tive
co
nta
c
t
po
int
of
t
h
e e
xh
aust
g
as
o
ver
h
eat
co
ntr
oll
er
(149
ȕ
)
Ch
e
c
k
co
nne
c
ti
o
n
of
t
h
e
o
ver
h
eat
co
ntr
oll
er.
R
e
mo
ve t
h
e
PCB
an
d ch
e
c
k
, w
it
h
a tester
,
t
h
e resistan
c
e
(
M
Ω d
e
f
e
c
t
)
.
If
t
h
e tr
o
u
bl
e
co
ntinues
d
es
p
ite t
h
e
ch
e
c
kin
g of
a
bo
ve ite
m
s
,
re
pl
a
c
e t
h
e
PCB
.
Cause
Check method