Part Number
550-110-290/0107
3
GOLD CGt Gas-Fired Water Boiler — Boiler Manual
Water piping — multiple zones
(continued)
Figure 18
Zoning with circulators
— return water 130°F or higher.
Figure 19
Zoning with zone valves
— return water 130°F or higher.
1
Boiler isolation (balancing) valves
2
Flow/check valve
3
System or zone circulator
5
Zone valve
6
Drain valve
9
Relief valve
10
Automatic air vent (with diaphragm-type expansion tank), or con-
nect 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
13
Air separator with automatic vent, if used (Note that the fill valve
must always be connected to the expansion tank.)
4c
For systems with possible
low return-water temperature
(such as converted gravity systems,
radiant heating systems and heat pump systems), refer to the special piping suggestions of
Figures 0 – 1, page 5, as applies. Failure to prevent sustained low return water tempera-
ture to the boiler could cause corrosion of the boiler sections, resulting in severe personal
injury, death or substantial property damage.
