Boiler Piping
Connect the expansion tank to an air separator
only if the air separator is located on the suc-
tion side (inlet) of the system circulator.
Always locate and install the system fill con-
nection at the same location as the expansion
tank connection to the system.
Diaphragm (Bladder) Expansion Tank
Always install an automatic air vent on the top
of the air separator to remove residual air from
the system.
Closed-Type (Standard) Expansion Tank
It is recommended to pitch any horizontal pip-
ing upwards toward the expansion tank 1 inch
per 5 feet of piping. Use 3/4” piping for the
expansion tank to allow air within the system
to rise.
DO NOT install automatic air vents on a
closed-type expansion tank system. Air
must remain in the system and be
returned to the expansion tank to pro-
vide an air cushion. An automatic air
vent would cause air to be vented from
the system resulting in a water-logged
expansion tank.
Circulator
The PRESTIGE must be supplied with a
Central Heating CH circulator. The circulator
when wired directly to the PRESTIGE will
allow for domestic hot water priority and to
provide circulation for the freeze protection
feature of the boiler control. See Graph 1 or
Graph 2 on page 68 for pressure drop and min-
imum flow rate through the boiler.
Sizing Primary Piping
See Fig. 9 through 15, pages 21 - 25, for rec-
ommended piping arrangements based on vari-
ous applications. Size the piping and system
components required in the space heating sys-
tem, using recognized design methods.
Domestic Hot Water System Piping
See Fig. 9 , page 21 for recommended piping to
a DHW system. This recommended piping
configuration ensures priority is given to the
production and recovery of the DHW.
The piping for the DHW is separate from the
boiler system piping and does not require a pri-
mary / secondary piping configuration.
To wire the DHW circulator to the boiler con-
trol module reference Section VIII - External
Wiring.
System Piping - Zone Circulators
Connect the PRESTIGE to the system piping
as shown in Fig. 10 page 22 when zoning with
zone circulators.
The installer must provide a separate circulator
for each zone of space heating as well as the
boiler circulator.
To ensure adequate flow rate through
the PRESTIGE, maintain a minimum 1-
1/4 inch diameter on the system piping
connecting the unit to and from the pri-
mary / secondary connection.
NOTICE
CAUTION
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