IBC VFC 15-150 Installation And Operating Instructions Manual page 27

WARNING
Close fill valve after any
addition of water to the
system, to reduce risk of
water escapement.
NOTE
Full sized application
drawings can be downloaded
from our web site.
www.ibcboiler.com
NOTE
The boiler, when used
in connection with a
refrigeration system,
must be installed so the
chilled medium is piped in
parallel with the boiler with
appropriate valves to prevent
the chilled medium from
entering the boiler.
NOTE
The boiler piping system of
a hot water boiler connected
to heating coils located in
air handling units where
they may be exposed to
refrigerated air circulation
must be equipped with
flow control valves or other
automatic means to prevent
gravity circulation of the
boiler water during the
cooling cycle.
INSTALLATION
VFC 15-150, VFC 45-225 MODULATING GAS BOILERS
Do not place any water connections overhead the boiler; leaks can damage
the fan & controls. If needed, create a shield over the louvered top of the cover,
but allow clearance for airflow and service access.
For best results, use a Primary: Secondary piping system, with a pumped
boiler loop using 1-1/4" piping for the 15-150 and 1-1/2" for the 45-225. Heat
exchanger head for both models is approx. 7' at 14 gpm, and 12' at 22 gpm
so an inexpensive fractional horsepower pump is normally adequate. Primary/
Secondary piping ensures adequate flow and de-couples Δ°T issues (boiler vs.
distribution). Aim for a 20° to 30° F Δ°T across the heat exchanger at high fire
(there is a boiler protection throttle fence limiting the Δ°T to 40°F).
Figure 24: Basic Primary/Secondary piping concept
Figure 25: Important Primary/Secondary piping details
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