Navien NP-180, Service Manual

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©N
avien
Am
eri
c
a
I
n
c
. 20
1
0
NR/NP
series servi
c
e Manua
l
2
5
Versi
o
n 2.0
4. System Details
4.1. Schematic and Flow Diagram
4.1.1. NR-A Model
H
o
t
w
ater
su
pply
Cold w
ater
su
pply
F
ue
l g
as
in
l
et
R
e
c
ir
c
u
l
ati
o
n
Exh
aust
p
i
p
e
intake air
d
u
c
t
F
an
mo
t
o
r
Mani
fold
B
urner
P
ri
m
at
y
H
/E
B
u
ff
er tank
Se
co
n
d
ar
y
H
/E
Flow
sens
o
r
Ch
e
c
k v
/
v
C
ir
c
u
l
ati
o
n
p
u
mp
Water a
dj
ust
m
ent v
/
v
Main
g
as v
/
v
3-
Wa
y
v
/
v