Weil-McLain 550-110-260/0107 manual 3d Piping — low temp systems continued

GOLD CGs Gas-Fired Water Boiler — Boiler Manual

3d Piping — low temp systems (continued)

Figure 8	Primary/secondary piping	Figure 9	Primary/secondary piping
	Zoning with circulators		Zoning with zone valves

1Boiler isolation (balancing) valves

2Flow/check valve

3System or zone circulator

4System temperature gauges

5Zone valve

6Drain valve

7System temperature valves (see instruc- tions to the left for adjusting valves)

8Blend temperature gauge

9Relief valve

10Automatic 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 waterlog- ging of the expansion tank.

11Fill valve

12Diaphragm-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 5, page 15.)

13Air 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.)

Part number 550-110-260/0107

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