GWS
Gas-Fired Water Boilers –
Boiler Manual
10
Part Number 550-110-732/0703
Figure 3
Diaphragm- or bladder-type expansion tank:
Piping to single-zone system using
diaphragm-type or bladder-type expansion
tank. See Table 5, page 9, for piping sizes.
Figure 4
Closed-type expansion tank: Piping to
single-zone system using closed-type
expansion tank. See Table 5, page 9, for
piping sizes.
Figure 5
Piping refrigeration systems
3
Install water piping
continued
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.
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.
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.
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 bypass piping (see page 11) 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.
