Crown Boiler BWF Series Installation Instructions Manual page 23

7. Water Piping (continued)
not run relief valve discharge piping through an
area that is prone to freezing. The termination
of the relief valve discharge piping must be
in an area where it is not likely to become
plugged by debris.
If necessary, the relief valve may be installed
in the supply piping as shown in Figure 7.2.
When this is done, the relief valve must be as
close to the boiler supply tapping as possible
with no intervening shut-off valves.
2. Circulator (Required) - The circulator is
shipped loose with the boiler. Fittings are
provided to mount it on the boiler return
as shown in Figure 7.3, however it can be
installed on the boiler supply. If the circulator
is moved to the supply it should be positioned
just downstream of the expansion tank as
shown in Figure 7.3.
3. Expansion Tank (Required) - If this boiler is
replacing an existing boiler with no other
changes in the system, the old expansion tank
can generally be reused. If the expansion tank
must be replaced, consult the expansion tank
manufacturer's literature for proper sizing.
4. Fill Valve (Required) - Either a manual or
automatic fill valve may be used. The ideal
location for the fill is at the expansion tank.
109836-01 - 04/20
Figure 7.3: Standard Boiler Piping
5. Automatic Air Vent (Required) - At least one
automatic air vent is required. Manual vents will
usually be required in other parts of the system
to remove air during initial fill.
6. Low Water Cut-Off (factory supplied) This boiler
is equipped with a low water cut-off (LWCO)
that prevents the boiler from firing if there is
inadequate water in the boiler. This LWCO is an
automatic reset type, meaning that it will allow
the boiler to restart automatically if the low water
condition is corrected. This LWCO satisfies the
requirements of most installation codes used
for residential installations, however some
jurisdictions may require a manual reset low
water cut-off which requires a reset button to be
pushed to restart the boiler.
If a manual reset LWCO is required, it must
be installed in the supply piping just above
the boiler in accordance with the LWCO
manufacturer's instructions (the factory supplied
LWCO is left in place). No intervening valves
may be installed between an externally piped
LWCO and the boiler. Wire an external manual
reset LWCO to either break120VAC power to
the boiler, or break the external limit connection
shown in Section 9.
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