Circulator Zoning - Primary/Secondary - Weil-McLain WMB-155C Manual

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AquaBalance
17 Primary/Secondary System Piping
Circulator zoning – primary/
secondary
See Figure 50.
This configuration is for circulator-zoned systems using
1.
a boiler loop connected as a secondary circuit off of a
primary system loop. Systems zoned with circulators
must pipe the boiler loop as a secondary circuit as show.
2. Install a separate circulator (supplied by installer) for
each zone capable of delivering the proper flow and
head as shown.
Expansion Tank required
1. Provide a system expansion tank following the guide-
lines on pages 36 or 37.
2. DO NOT use a closed-type tank if connecting to a boiler
that is equipped with an automatic vent.
Overriding the Outdoor Reset function by
connecting space heating zones to inputs and
outputs intended for DHW applications may
violate Section 303 of the 2007 Energy Act.
See page 99 for compliance information and
exemptions.
Controlling the Zones
1. The control can be used to control space heating only,
domestic water heating only, or both. Refer to field wir-
ing, beginning on page 47, for instructions on wiring
to circulators.
2. The boiler and circulators can also be operated by a
zone controller.
Figure 50 and Figure 51
WMB-155C
1 wall mount boiler
2 Relief valve, supplied by Installer, field piped —
MUST be piped to boiler supply connection — see
page 9 for information
3 Isolation valves
4 System circulator
5 Expansion tank, diaphragm type, if used
6 Air separator
7 Flow/check valves
8 Purge/drain valves (Installer supplied)
9 Auto air vent
10 Zone valves
40
M -
ALL OUNT GAS FIRED WATER BOILER
11 Primary/secondary connection (tees no more
than 12 inches apart)
12 Expansion tank, closed type, if used (some
chiller systems may use a diaphragm-type expan-
sion tank)
13 Water chiller
14 Check valve
15 Y-strainer
16 Balancing valve
17 Make-up water supply – Use applicable codes to
determine if backflow preventers, pressure reduc-
ing valves, and fill valves may be required
— C
OMBI
(continued)
Figure 50
18 By-pass pressure regulator, REQUIRED for zone
valve systems unless other provision is made
19 High limit temperature control
20 Zone circulator
21 Pressure/temperature gauge, supplied with boiler,
field piped
22 Heating circuits
23 Additional heating circuits, if any
24 Mixing valve, if any
Boiler Manual
Part number 550-100-305/1016