Additional Limit Control; Backflow Preventer; Boiler System Piping Applications; Expansion Tank And Makeup Water - Prestige Solo 175 Installation And Maintenance Manual

Boiler Piping

Additional Limit Control

If a separate LWCO device is required by cer-
tain local jurisdictions or when the boiler is
installed above the system piping, the follow-
ing guidelines must be followed:
- The LWCO device must be designed
for water installations, electrode probe-
type is recommended.
- The LWCO device must be installed in
a tee connection on the boiler supply
piping above the boiler.
- Wiring of the LWCO device to the
PRESTIGE is done directly onto the
24V terminal strip, reference Fig. 20
page 32 for available terminals for an
external limit (manual or auto reset).
If the installation is to comply with ASME or
Canadian requirements, an additional high
temperature limit may be needed.
local code requirements to determine compli-
ance. The limit should be installed as follows:
- Install the limit in the boiler supply pip-
ing between the boiler and any isolation
valve.
- Maximum set point for the limit is
194ºF.
- For wiring of the limit reference Fig. 20,
page 32, using the external limit/manual
reset terminals on the 24V terminal strip.
This will provide a "hard" lockout
requiring a manual reset of the control.

Backflow Preventer

- Use a backflow preventer valve in the
make-up water supply to the unit as
required by local codes.

Boiler System Piping Applications

BEST PRACTICE
It is recommended on all piping applica-
tions to utilize a primary/secondary pip-
ing arrangement as a means to provide
freeze protection of the boiler, which is an
integral function of the boiler control and
to utilize the full function of the integral
boiler circulator while maintaining the
minimum flow rate, see Graph 1, page 68.
For other piping arrangements, consult
the Engineering Department at Triangle
Tube or consult other approved/recog-
nized design arrangements.
BEST PRACTICE
On piping applications utilizing a single
zone or other recognized piping design
Consult
arrangements, it is recommended that the
installer uses flow/check valves with
weighted seats at or near the appliance to
prevent gravity circulation.

Expansion Tank and Makeup Water

Ensure the expansion tank is properly sized for
the boiler volume (5 gallons [19 L]) and the
system volume and temperature.
CAUTION
Undersized expansion tanks will cause
system water to be lost through the pres-
sure 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.
The expansion tank must be located as shown
in Fig. 7 and Fig. 8 on page 19 when using a
primary/secondary piping arrangement or as
per recognized design methods. Refer to the
expansion tank manufacturer instructions for
additional installation details.
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