Zone Valve Zoning - Direct Connection - Weil-McLain ECO 70 Manual

TM -
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AS FIRED WATER BOILER
Direct Connect System Piping
ZONE VALVE zoning –
(Shown with optional DHW piping)
See Figure 45.
1. This configuration is for zone valve systems that qualify to
use direct connection piping based on the criteria on page 37
only. If system does not qualify, pipe using primary/secondary
piping. See pages 43-49 for piping suggestions and guidelines.
2. Systems zoned with zone valves MUST use a by-pass pressure
regulator (Taco 3196 shown).
3. Install a system circulator (supplied by installer) capable of
delivering the proper flow and head as shown.
Expansion Tank required
1. Provide a system expansion tank following the guidelines on
page 37 or page 38.
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 59 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 70 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 connecting
space heating zones to inputs and outputs intended
for DHW applications may violate Section 303 of
the 2007 Energy Act. See page 119 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 field wiring,
beginning on page 56, for instructions on wiring to zone valves.
2. The boiler and zone valves can also be operated by a
Weil-McLain WMZV zone controller.
1 ECO wall mount boiler
2 Indirect Water Heater, if used
3 Relief valve, supplied with boiler, field piped — MUST
be piped to boiler supply connection — see page 12 for
information
4 Relief valve piping to drain — see page 40
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 550-142-122/0513
— Boiler Manual
direct connection
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 deter-
mine if backflow preventers, pressure reducing valves,
and fill valves may be required
(continued)
Zone valve zoning direct
connection (system circulator provides flow
for system)
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.
This is a common legend for all piping diagrams, not
all items listed appear in every figure.
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, field
piped
27 Heating circuits
28 Additional heating circuits, if any
29 Boiler circulator, if any
30 Mixing valve, if any
41