Boiler Manual
Part Number 550-110-593/1099 25
3System or zone circulator
7System temperature valves (see instructions to the left for
adjusting valves)
8Blend temperature gauge
9Relief valve
10 Automatic air vent (with diaphragm-type expansion
tank), or connect to tank fitting (closed-type expansion
tank). DO NOT use an automatic air vent when using
closed-type expansion tank. It would allow air to leave
the system, causing waterlogging of the expansion tank.
11 Fill valve
12 Diaphragm-type or bladder-type expansion tank, if used
(For closed-type expansion tank, pipe from top of air
separator to tank fitting as in Figure 10.)
System-bypass piping —
for converted gravity (or steam) systems
Figure 17 System-bypass piping
Zoning with zone valve or circulators, return
water 130 °F or higher.
(Alternative to boiler-bypass piping Figures
15 and 16)
Figure 18 Piping refrigeration systems Prevent chilled water from
entering boiler
Water piping — Refrigeration system
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 18 for
typical installation of balancing
valve and check valve.
59314
10
Cold
water
fill
11
12
9
8
7a 7b
Alternate
circulator
location
To systemFrom system
GOLD
CGa
59315
Water
chiller
Expansion tank
Circulator
Check
valve
Strainer
Boiler
Shut-off
valve
System
supply
System
return
Balancing
valve
GOLD
CGa
3f3gIf 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.