Weil-McLain Evergreen EVG 110, Manual

Page: 49 / 144

Figure 53
Zone valve zoning — primary/secondary
connection — a system circulator is required
LEGEND for Figure 53 . Note: This is a common legend for all piping diagrams.
Not all items listed appear in every fi gure.
1
Evergreen
® 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 48
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)
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
21 By-pass pressure regulator, REQUIRED for zone valve
systems unless other provision is made
22 High limit temperature control (If used)
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
Part number 550-100-191/0917
49
®
g
as-fired water boiler —
70/110/155
Boiler Manual
ZONE VALVE zoning –
primary/
secondary
(Shown with optional DHW piping)
See Figure 53 .
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 Direct Connect System Piping 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 45 or 46 .
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 139 to ensure compliance with the 2007
Energy Act. See Advanced Manual to confi gure 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 139 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 54 , 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
respective circulator output. For DHW Priority applications,
wire aquastat to Input 1 and assign to Priority 1. See Field
wiring instructions, beginning on page 54 , for details.
3. For more than 3-zones, use Weil-McLain WMZV zone valve
controller.
Connect zone valve end switches to Priority 2 input.
Connect system circulator to Circ. 2 output.
Use isolation relays if connecting 3-wire zone valve
end switches to the input.
Primary/Secondary System Piping
-
Single Boiler System
(continued)
See Advanced Manual for Multiple Boiler Systems