Williamson OWB Series 2 User Manual page 8

OWB & OWT Series 2 Oil-Fired Water Boilers – Boiler Manual
4 Connect water piping
Figure 3 Diaphragm- or bladder-type expansion
tank:
Piping to single-zone system using
diaphragm-type or bladder-type expansion
tank. See Table 4, page 7, for piping sizes.
Closed-type expansion tank: Piping to
Figure 4
single-zone system using closed-type
expansion tank. See Table 4, page 7, for
piping sizes.
8
continued
Use Figure 3 or Figure 4 only for systems designed
for return water at least 130 °F. For systems with
low return water temperature possible, such as
converted gravity systems and radiant heating
systems, install by-pass piping (see page 9) to
protect boiler against condensation. Failure to
prevent low return water temperature to the boiler
could cause corrosion of the boiler sections or
burners, resulting in severe personal injury, death
or substantial property damage.
If system includes radiant heating circuits, provide
piping and controls to regulate the temperature
supplying the radiant circuits. Failure to comply could
result in substantial property damage.
Install boiler so that chilled medium is piped in
parallel with heating boiler. Use appropriate valves to
prevent chilled medium from entering boiler. Consult
I=B=R Installation and Piping Guides.
If boiler is connected to heating coils located in
air handling units where they can be exposed to
refrigerated air, use flow control valves or other
automatic means to prevent gravity circulation
during cooling cycle. Circulation of cold water
through the boiler could result in damage to the heat
exchanger, causing possible severe personal injury,
death or substantial property damage.
Water piping — refrigeration systems
Prevent chilled water from entering boiler
Install boiler so that chilled medium is piped in parallel with the
heating boiler. Use appropriate valves to prevent chilled medium
from entering boiler. See Figure 5 for typical installation of
balancing valve and check valve.
Figure 5 Piping refrigeration systems
Part Number 550-110-832/1014