Circulator Zoning - Primary/Secondary - Weil-McLain Series 2 Manual

® S
ERIES
Primary/Secondary System piping
Circulator zoning –
(Shown with optional DHW piping)
See Figure 57 .
1. This confi guration is for circulator-zoned systems using 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 fl ow and head as
shown.
Expansion Tank required
1. Provide a system expansion tank following the guidelines
on page 47 or 48 .
2. DO NOT use a closed-type tank if connecting to a water
heater that is equipped with an automatic vent.
Domestic Hot Water (DHW) tank, if used
DHW direct connection — Pipe from the near-boiler piping
1.
to the DHW tank's boiler connections as shown.
2. DHW as zone—A DHW tank can be connected as a zone
if a DHW tank is NOT already connected to the boiler. To
provide DHW priority operation, use a zone controller.
See notices on page 63 to ensure compliance with the 2007
Energy Act.
3. DHW Priority operation—The ECO control turns off space
heating to the HEAT zones during domestic water heating
calls on the DHW input. The MAX ON TIME setting can
be adjusted to limit how long this occurs. Set the MAX ON
TIME to "0" to disable domestic priority. See page 74 for
setting instructions.
4. If NOT connecting a water heater, do not use the DHW
input or DHW Circulator output on the ECO control.
Overriding the Outdoor Reset function by con-
necting space heating zones to inputs and outputs
intended for DHW applications may violate Sec-
tion 303 of the 2007 Energy Act. See page 127 for
compliance information and exemptions.
Controlling the Zones
1. The ECO control can be used to control space heating
only, domestic water heating only, or both. Refer to fi eld
wiring, beginning on page 60 , for instructions on wiring to
circulators.
2. The boiler and circulators can also be operated by a
Weil-McLain WMCR zone controller.
LEGEND for Figure 57 and Figure 58
1 ECO wall mount boiler
2 Indirect Water Heater, if used
3 Relief valve, supplied with boiler, fi eld piped — MUST
be piped to boiler supply connection — see page 14 for
information
4 Relief valve piping to drain — see page 50
5 DHW circulator
6 Isolation valves
7 System circulator
8 Expansion tank, diaphragm type, if used
9 Air separator
10 Flow/check valves
11 Purge/drain valves
(one drain valve shipped loose with boiler)
52
2
-
G
AS FIRED WATER BOILER
primary/secondary
12 Auto air vent
13 Zone valves
14 Primary/secondary connection (tees no more than 12
inches apart)
15 Expansion tank, closed type, if used (some chiller
systems may use a diaphragm-type expansion tank)
16 Water chiller
17 Check valve
18 Y-strainer
19 Balancing valve
20 Make-up water supply – Use applicable codes to
determine if backfl ow preventers, pressure reducing
valves, and fi ll valves may be required
— Boiler Manual
(continued)
Figure 57 Circulator zoning plus optional DHW piping
Note: This is a common legend for all piping diagrams.
Not all items listed appear in every fi gure.
21 By-pass pressure regulator, REQUIRED for zone valve
systems unless other provision is made
22 High limit temperature control
23 DHW tank boiler water supply connection, when used
24 Zone circulator
25 DHW tank boiler water return connection, when used
26 Pressure/temperature gauge, supplied with boiler, fi eld
piped
27 Heating circuits
28 Additional heating circuits, if any
29 Boiler circulator, if any
30 Mixing valve, if any
31 Low Water Cut-Off (If used)
Part number 550-142-190/1218