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Viega Hydronic Mixing Block User Guide
UG-HC 566234 0720 Hydronic Mixing Block
P
iping
■
This dr
awing shows syst
em piping
concept only
. Installer is r
esponsible
for all equipment and detailing requir
ed by local codes.
■
Siz
e header piping for maximum flow
velocity of 2 ft./sec.
■
All other piping should be siz
ed for a
maximum flow velocity of 4 ft./sec.
■
Install a minimum of 12 diamet
ers
of str
aight pipe upstr
eam of all
cir
culat
ors and check valves.
■
Install isolating flanges or isolating valves on all cir
culat
ors.
■
Install pur
ging valve(s) on all cir
cuits.
■
All closely spaced t
ees shall be
within 4 pipe diamet
er cent
er
-t
o-
cent
er spacing.
■
Install minimum of 6 pipe diamet
ers
of str
aight pipe upstr
eam and
downstr
eam
of
all
closely
spaced
tees.
■
Differ
ential pr
essur
e bypass valve
pr
events flow noise under par
tial
load conditions (some zone valves closed).
■
Set differ
ential pr
essur
e bypass
valve t
o delta P of distribution
syst
em with all zones open + 1 psi
■
Not all components may be r
equir
ed
depending on contr
ol str
at
egy (i.e.
constant cir
culation).
Legend:
4-W
ay
Mixing
Valve
and
Mot
or
Hydr
onic Mixing Block
P
ressur
e Differ
ential Bypass V
alve
Spring check
S
tainless Manifold with Flow Gauges
Cir
culat
or
Baseboar
d Z
one(s)
Dr
aw Off (P
ur
ge V
alve)
Diaphr
agm-
Type Expansion T
ank
Mak
e-up W
at
er
Zone V
alve
Conceptual
P
iping
Diagr
am
Zone Contr
ol
Outdoor
Sensor (S3)
Boiler
Sensor (S1)
P
rimar
y L
oop P
ump (P1)
Boiler Relay
P2
1 S
tage
T-S
tat
1 S
tage
T-S
tat
1 S
tage
T-S
tat