Zone Valve Zoning - Primary/Secondary - Weil-McLain Series 2 Manual

® S
ERIES
Primary/Secondary System piping
ZONE VALVE zoning –
secondary
(Shown with optional DHW piping)
See Figure 56 .
1. This confi guration is for zone valve systems using a boiler loop
connected as a secondary circuit off of a primary system loop.
Systems whose fl ow characteristics do not comply with those
listed in must pipe the boiler loop as a secondary circuit as
show.
2. Systems zoned with zone valves MUST use a by-pass pressure
regulator.
3. Install a system circulator (supplied by installer) 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
1. DHW direct connection—Pipe from the near-boiler piping
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 zone
valves.
2. The boiler and zone valves can also be operated by a Weil-
McLain WMZV zone controller.
LEGEND for Figure 56 .
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)
Part number 550-142-190/1218
2
-
G
AS FIRED WATER BOILER
primary/
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 56 Zone valve zoning — primary/secondary
connection — a system circulator is required
Connect zone valve end switches to HEAT input.
Connect system circulator to HEAT Circ. output.
Use isolation relays if connecting 3-wire zone valve
end switches to the HEAT input.
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)
51