Install Instructions
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.OTEThis is a common legend for all piping diagrams, not
all items listed appear in every figure.
Evergreen boiler
Indirect Water Heater, if used
Relief valve, supplied with boiler, field piped — MUST
be piped to boiler supply connection — see page 39 for
information
Relief valve piping to drain — see page 39.
DHW circulator
Isolation valves
System circulator
Expansion tank, diaphragm type, if used
Air separator
10 Flow/check valves or spring check
11 Purge/drain valves
(one drain valve shipped loose with boiler)
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
21 By-pass pressure regulator,
Recommended 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
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
30 Mixing device, if any
31
System supply and return sensors: Strap system sensors
to lines as shown, at least 6 pipe diameters (but no more
than 3 feet) from boiler connection tees.
Part number 550-100-131/0715
– 42 –
™
GAS-FIRED WATER BOILER — Boiler Manual
Circulator zoning – primary/secondary
(Shown with optional DHW piping)
See Figure 50.
1. This configuration 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 flow and head as shown.
3. The flow/check valve shown on the boiler outlet piping prevents
gravity circulation in the boiler loop during DHW heating.
Use AT LEAST the -).)-5- pipe size shown in
Figure 44, page 37 on all boiler loop piping (connecting
boiler to and from the primary/secondary connection,
item 14). 5SEONLYPRIMARYSECONDARYPIPINGAS
SHOWN Failure to follow these guidelines could result
in system problems.
Expansion Tank required
1. Provide a system expansion tank following the guidelines on
page 40.
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. See notices on
page 127 to ensure compliance with the 2007 Energy Act.
3. DHW Priority operation—The 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.
Overriding the Outdoor Reset function by setting control
to DHW mode when system is intended for space heat-
ing may violate Section 303 of the 2007 Energy Act. See
page 127 for compliance information and exemptions.
Controlling the circulators
1. The control can control up to four circulators (boiler circulator
and three others). Refer to Field wiring, beginning on page 50, for
instructions on wiring to circulators.
2. The factory default settings are: all three inputs are set up for
Space Heating (
Priority 2). Each input correlates to its respec-
&IGURE Circulator zoning plus optional DHW piping
tive circulator output. For DHW applications, set Input 1
to Priority 1. See Field wiring instructions, beginning on
page 50, for details.
3. For more than 3-zones, use Weil-McLain WMCR zone Circ
controller.
System piping - Single Boiler Systems (continued)
See Advanced Manual for Multiple Boiler Systems
-).)-5-
Boiler loop pipe size
Evergreen 220
Evergreen 299/300, 399
1¼”
1½”
See CAUTION at left.