Weil-McLain Evergreen EVG 220 Manual page 47

®
gas
System piping -
See Advanced Manual for Multiple Boiler Systems
DHW as a zone — CIRCULATOR zoning
primary/secondary
1. This configuration is for circulator-zoned systems with a
DHW tank piped as a zone in the system. The boiler is
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.
Use at least the MINIMUM pipe size shown in
Figure 47, page 39 on all boiler loop piping (con-
necting boiler to and from the primary/second-
ary connection, item 14). Use only primary/
secondary piping as 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 42.
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, as shown
1. Install the DHW tank as a system zone. The DHW tank can
be piped as a zone ONLY if a DHW tank is NOT connected to
the boiler directly.
2. Wire the DHW aquastat and circulator to an input/output
pair, normally Input/Output 1. See notices on page 129 to
ensure compliance with the 2007 Energy Act. See the Advanced
Manual to configure Boiler Pump to run during DHW demands
and change TARGET MOD SENSOR to System Supply.
3. DHW Priority operation— Using Priority 1 for DHW (default)
will turn off lower priorities during DHW calls. The MAX ON
TIME setting can be adjusted to limit how long this occurs.
Use Priority 2 or 3 for DHW if DHW priority is not desired.
Overriding the Outdoor Reset function by setting
control to DHW mode when system is intended for
space heating may violate Section 303 of the 2007
Energy Act. See page 129 for compliance informa-
tion 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 52,
for instructions on wiring to circulators.
1
Evergreen boiler
2
Indirect water heater, if used
3
Relief valve, supplied with
boiler, field piped — MUST
be piped to boiler supply
connection — see page 37 for
information.
4
Relief valve piping to drain —
see page 41.
5
DHW circulator.
6
Isolation valves.
8
Supplementary expansion
tank, diaphragm type, if used.
Part number 550-100-131/0120
-
fired water boiler
Single Boiler Systems
See Figure 56.
Legend — Figure 56
9 Air separator.
10 Flow/check valves or spring check.
11 Purge/drain valves (one drain
valve is supplied loose with the
boiler).
12 Boiler circulator.
14 Primary/secondary connection (tees
no more than 12 inches apart)
20 Make-up water supply.
22 High limit temperature control,
when required by local code or
for a radiant system.
23 Backflow preventer, if used.
— 220/299/300/399 Boiler Manual
Figure 56
Circulator zoning with DHW as a zone
2. The factory default settings are: all three inputs are set up
for Space Heating (
respective circulator output. For DHW Priority applications,
wire aquastat to Input 1 and assign to Priority 1. See Field wiring
instructions, beginning on page 52, for details.
3. For more than 3-zones, use Weil-McLain WMCR zone
Circ controller. See EVG Advanced Manual for proper wiring.
24 Zone circulators.
25 Pressure reducing valve, if
used.
26
Pressure/temperature
gauge, supplied with boiler,
field piped.
27 Quick-fill valve, if used.
28 Heating circuits.
29 Additional heating circuits, if
any.
31 System supply and return sen-
sors: Strap system sensors to
lines as shown, at least 6 pipe
(continued)
MINIMUM
Boiler loop pipe size
Evergreen 220
Evergreen 299/300, 399
See CAUTION at left.
Priority 2)
. Each input correlates to its
diameters (but no more than
3 feet) from boiler connec-
tion tees.
32
Low Water Cut-off
= Items supplied with boiler
— all other items supplied by
installer.
1¼"
1½"
– 47 –