18-CG03D1-4
16
Circulator
Pu
m
p
4-W
a
y
Mot
o
riz
e
d
V
alv
e
Boiler
Back
F
lo
w
P
rev
ent
e
r
Globe
Va
lv
e
Globe
Va
lv
e
Globe
Va
lv
e
P
ressur
e
Reduc
er
P
ressur
e
G
auge
Air
S
epar
at
or
Expansion
Ta
nk
T
ypical
S
y
st
em
Piping
Diagr
am
P
rimar
y
S
ec
ondar
y
L
o
op
with
4-wa
y
M
ot
oriz
ed
V
a
lv
e
with
Cir
culat
o
r
in
S
ec
ondar
y
L
o
op
Only
L
o
w
Temper
arur
e
with
L
o
w
M
ass
H
eat
Emitt
ers
or
High
Temper
atur
e
w
ith
High
or
L
o
w
M
ass
H
eat
Emitt
ers
Return
W
a
te
r
Te
mper
atur
e
Se
n
so
r
Supply
W
at
er
Te
mper
atur
e
S
ensor
Return
wat
er
te
mper
atur
e
must
be
abo
v
e
110
O
F
Heat
Emitt
er
1
2
1
2
NO
TES:
P
rot
ec
ts
boiler
fr
om
to
o
lo
w
return
wat
er
te
mper
atur
e
a
nd
condensation.
L
o
cat
e
the
cir
culat
o
r
inlet
close
to
the
co
nnec
tion
point
o
f
the
expansion
tank,
but
allo
w
a
t
least
the
equiv
alent
o
f
1
0
to
1
2
p
ipe
diamet
ers
b
etw
een
the
cir
culat
o
r
pump
inlet
and
the
expansion
tank
to
re
duc
e
the
p
ossibilit
y
of
pump
noise
and
facilitat
e
air
re
m
o
v
a
l.
Return
Supply
Relief
Va
lv
e
Exhaust
Ve
n
t
