Install Instructions

&IGURE Circulator zoning with high- and low-temperature
heating zones
Primary/Secondary System piping (continued)
Circulator zoning – Multiple
temperature zones with primary/
secondary
(Shown with optional DHW piping)
See Figure 52.
1. This configuration is for circulator-zoned systems
with high- and low-temperature heating zones
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 shown.
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
guidelines on page 43 or page 44.
2. DO NOT use a closed-type tank if connecting to
a water heater that is equipped with an automatic
vent.
System setup and settings
1. Hi-temp emitters may be baseboards, radiators, fan
coils, or heat exchangers.
2. Add a mixing device (Figure 52, item 30) to help
ensure supply water temperature will not exceed
the maximum allowable for the radiant system.
3. Heating zone supply water temperature settings
should be selected for the hi-temp zones. The
mixing device regulates supply temperature to the
lower-temp zones
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 do-
mestic 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 ap-
plications 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, domes-
tic water heating only, or both. Refer to field wiring, beginning on
page 56, for instructions on wiring to circulators.
2. The boiler and circulators can also be operated by a Weil-McLain
WMCR zone controller.
Part number 550-142-122/0513
49
TM
GAS-FIRED WATER BOILER — Boiler Manual