Expansion Tank And Makeup Water; Diaphragm Expansion Tank; Circulator; Sizing Primary Piping - TriangleTube PRESTIGE Excellence 110 Installation & Maintenance Manual

CHAPTER 4 - BOILER PIPING
4.8.

Expansion Tank and Makeup Water

Ensure the expansion tank is properly sized for the boil-
er volume, (5 gallons [19 L] for the PRESTIGE Excellence),
the system water volume, and the system water tem-
perature.
CAUTION
Undersized expansion tanks will cause system
water to be lost through the pressure relief
valve and cause additional makeup water to be
added to the system. Eventual boiler heat ex-
changer failure can result due to this excessive
makeup water addition.
The expansion tank must be located as shown in Fig. 7
on page 15 when using a primary/secondary piping
arrangement. Refer to the expansion tank manufactur-
er for additional installation details.
Connect the expansion tank to an air separator only if
the air separator is located on the suction side (inlet)
of the system circulator. Always locate and install the
system fill connection at the same location as the ex-
pansion tank connection to the system.
CAUTION
The expansion tank must be located directly
on the PRESTIGE Excellence return pipe, before
the return check valve. Incorrect expansion
tank location will cause system water to be lost
through the pressure relief valve and cause
additional makeup water to be added to the
system. Eventual boiler heat exchanger failure
can result due to this excessive makeup water
addition.

4.8.1 Diaphragm Expansion Tank

Always install an automatic air vent on top of the air
separator to remove residual air from the system.
4.9.

Circulator

The PRESTIGE Excellence is supplied with a Boiler circu-
lator that provides circulation for central/space heating
(CH) and Domestic Hot Water (DHW) production. See
Graph 1 on page 81 for pressure drop and minimum
flow rate through the boiler.
16

4.10. Sizing Primary Piping

See Fig. 8 on page 18 through Fig. 11 on page 21, for
recommended piping arrangements based on various
applications. Size the piping and system components
required in the space heating system using recognized
design methods.

4.11. System Piping - Zone Circulators

Connect the PRESTIGE Excellence to the system pip-
ing as shown in Fig. 8 on page 18 when zoning with
zone circulators.
The installer must provide a separate circulator for each
zone of space heating.
NOTICE
To ensure an adequate flow rate through the
PRESTIGE Excellence, the boiler supply and re-
turn piping size must be a minimum of 1 inch.

4.12. System Piping - Zone Valves

Connect the PRESTIGE Excellence to the system pip-
ing as shown in Fig. 9 on page 19 when zoning with
zone valves.
NOTICE
To ensure an adequate flow rate through the
PRESTIGE Excellence, the boiler supply and re-
turn piping size must be a minimum of 1 inch.

4.13. System Piping - Through Boiler

Primary / secondary piping is preferred, but is not re-
quired for smaller systems (1 to 3 zones) provided that
at least the minimum flow rate through the boiler is
maintained at all times. The internal circulator must be
able to overcome the pressure drop through the sys-
tem as well as the Prestige Excellence. See Graph 1 on
page 81 for pressure drop and minimum flow rate
through the boiler.
Fig. 10 on page 20 illustrates a multiple zone valve
system with a single system/boiler circulator. A by-pass
loop with a pressure differential valve must be installed
on the system piping.
Fig. 11 on page 21 illustrates a single zone system
utilizing the boiler circulator as the system circulator.