Weil-McLain Gold CGi 2 Series Manual page 25

CGi
GOLD GAS-FIRED WATER BOILER — SERIES 2 —
4d
Piping — low temperature systems
Figure 20
1
Boiler isolation (balancing) valves
2
Flow/check valve
3
System or zone circulator
4
System temperature gauges
5
Zone valve
6
Drain valve
7
System temperature valves (see instruc-
tions to the left for adjusting valves)
8
Blend temperature gauge
Part Number 550-110-710/1211
Primary/secondary piping
Zoning with circulators
Boiler Manual
Figure 21
Primary/secondary piping
Zoning with zone valves
9
Relief valve
10
Automatic air vent (with diaphragm-type expansion tank), or
connect to tank fitting (closed-type expansion tank).
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 17
13
Air separator and automatic vent, if used (Note that the fill valve
must always be connected to the expansion tank, regardless of
location of expansion tank, circulator or air separator.)
(continued)
DO NOT
.)
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