Navien NP-180, Service Manual

Page: 112 / 179

©N
avien
Am
eri
c
a
I
n
c
. 20
1
0
NR/NP
series servi
c
e Manua
l
11
0
Versi
o
n 2.0
5.21. 37Error
Error occurrence conditions and check items.
Description Error
37E
Internal water
leak
Check items
1
. Visua
lly ch
e
c
k
h
eat e
xch
an
g
er an
d p
i
p
in
g fo
r
l
eaks.
2.
Ch
e
c
k i
f
t
h
e
PCB w
ater
l
eve
l
sens
o
r
wo
rks n
o
r
m
a
lly
.
3
.
Ch
e
c
k i
f
t
h
e
PCB wo
rks n
o
r
m
a
lly
.
If
t
h
e
w
ater
l
eak sens
o
r si
g
na
l
is
d
ete
c
te
d wh
i
l
e t
h
e
w
ater
h
eater is
ON,
t
h
e s
y
ste
m
d
is
pl
a
y
s
37E (cl
eare
d m
anua
lly)
.
Th
e
w
ater
h
eater enters t
h
e
Loc
k
-O
ut
mod
e
(g
as va
l
ve an
d
i
g
niti
o
n trans
fo
r
m
er
clo
se
d),
an
d clo
ses t
h
e
flow co
ntr
ol
va
l
ve t
o
p
revent
f
urt
h
er
w
ater
l
eak.
Ȅ
Fo
r t
h
e
c
as
c
a
d
e s
y
ste
m
1
.
If
t
h
e
w
ater
l
eak si
g
na
l
is sense
d
in
o
ne
o
ut
of
t
wo
units
,
t
h
e s
y
ste
m bloc
ks
d
ire
c
t
w
ater
of
t
h
e a
ll
units t
o p
revent
w
ater
l
eak.
2.
If
t
h
ree
o
r
mo
re units are insta
ll
e
d,
t
h
e s
y
ste
m bloc
ks
cold w
ater
fo
r t
h
e
co
n
c
erne
d
unit
o
n
ly
.
3
.
To bloc
k t
h
e
cold w
ater
,
t
h
e s
y
ste
m compl
ete
ly clo
ses t
h
e
w
ater a
dj
ust
m
ent va
l
ve.
Is there any water leakage
inside water heater?
Is there any water leakage
detector normally
operating?
Yes
No
Replace water leakage detector
Replace leaking part
Yes
Check connector
No