IBC SL 28-160 Installation And Operating Instructions Manual page 25

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
SL 28-160 MODULATING GAS BOILER
System piping is connected to the boiler using the 1" NPT Male threaded fittings
on the right or left side connection ports. Unions and gate or ball valves at
the boilers supply and return water connections are recommended to simplify
servicing. Un-insulated hot water pipes must be installed with a minimum 1/4"
clearance from combustible materials.
Figure 26: Boiler trim basic options - side piping
Fluid fill is most often accomplished by using a boiler regulator & fill valve set
at 12 psig or more, with appropriate backflow prevention device as required
by local code. This is acceptable in areas where municipal water or well water
has been treated and filtered to remove excessive minerals and sediment, and
water chemistry is known to be suitable for closed loop hydronic systems. In
areas where water quality is in question, or when chemical treatment or glycol is
required, other options should be considered. Follow applicable Codes and good
piping practice.
There are a number of boiler feed and pressurization devices on the market
today that may be a better choice than a raw water fill from the mains. When
regular maintenance requires relief valve blow-off, the discharge may be directed
back into the pressurization unit for recycling of boiler fluid and chemicals
back into the system. In buildings that may be unoccupied for long periods of
time, pressurization units are useful to prevent flood damage should leakage
occur from any component in the system. An additional benefit is that backflow
prevention devices are not required when using these devices.
Do not place any water connections overhead the boiler; leaks can damage
the fan & controls. If needed, create a shield over the 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 SL 28-160. Heat exchanger head is only 0.5' at 5
USgpm and approximately 4' at 16 USgpm.
The minimum flow rate required through the heat exchanger is 4 USgpm with a
maximum of 16 USgpm allowed. 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).
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