Weil-McLain SVF 1500 Manual page 23

SVF
™
Series 1
Commercial Condensing Gas-Fired Water Boiler — Boiler Manual
Install water piping
WATER CHILLER systems — ZONE
VALVES primary/secondary
1. Th e chiller must be piped in parallel with the boiler.
2. Use appropriate valves to prevent chilled medium from entering boiler.
3. Circulator zoning option — Th e space heating system can be zoned with
circulators if a separate circulator is supplied for the chilled water loop. Install
a separate circulator for each zone.
4. Th e fl ow/check valve shown on the boiler outlet piping prevents gravity
circulation in the boiler loop during DHW heating.
Use at least the
on all boiler loop piping (connecting boiler to and from the primary/
secondary connection, item 21).
shown ensures the boiler loop will have suffi cient fl ow. For other
piping methods, see guidelines starting on page 15 .
If antifreeze is used in the system, consider the eff ects of antifreeze
on circulator sizing and DHW performance. Some local codes may
require double-wall DHW heat exchanger design. Use only the an-
tifreeze listed by Weil-McLain for use with this boiler. See page 111
for details.
Chilled medium, if used, is piped in parallel with heating boiler
as shown in Figure 20 . Use appropriate valves to prevent chilled
medium from entering boiler. If boiler is connected to heating
coils located in air handling units where they can be exposed to
refrigerated air, use fl ow control valves or other automatic means
to prevent gravity circulation during cooling cycle.
Expansion Tank required
1.
Provide a system expansion tank following the guidelines on page 16 .
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— Not recommended for this application.
3. System Priority choices:
a. DHW Priority – DHW is priority over space heating. Use Priority
1 for DHW; Priorities 2 and/or 3 for space heating. Th e control
will not run multiple priorities simultaneously.
b. Space Heating Priority – Space heating is priority over DHW. Use
Priorities 1 and/or 2 for space heating; Priority 3 for DHW. Th e
control will not run multiple priorities simultaneously.
c. No Priorities – Space heating and DHW can occur simultane-
ously at same Supply Max. temperature. Use only if DHW is a
zone in system. Assign DHW and Space heating to same Priority.
Do not use outdoor reset for this application.
Controlling the circulators
1. Th e control can control up to four circulators (boiler circulator and three
others). Refer to Field wiring, beginning on page 59 , for instructions on
wiring to circulators.
TM
1
SVF boiler
2 Indirect water heater (DHW), if used
3 Boiler relief valve (see page 14 for piping details)
4 Relief valve discharge piping (see page 14 for details)
5 DHW circulator
6 Isolation valves
7 System circulator (see information above for wiring)
9 Air separator [with automatic air vent only on systems using diaphragm
(or bladder) type expansion tank]
10 Flow/check valves
11 Purge/drain valves
12 Boiler circulator
13 Zone valves, typical
15 Closed-type expansion tank
Part number 550-100-250/0819
(continued)
See Figure 20 .
pipe size shown in Figure 11, page 16
Legend — Figure 20
Figure 20
Chilled water system plus optional DHW
piping — primary/secondary piping
2. Th e factory default sett ings are: all three inputs are setup for Space Heat-
ing (Priority 2). Each input correlates to its respective circulator output.
For DHW applications, assign DHW Input(s) to determined Priority (1,
2, or 3). Priority 1 is defaulted to DHW for DHW Priority applications.
3. For more than 3-zones, use Weil-McLain WMZV zone valve controller.
Connect zone valve end switches to a Space Heating
Priority input, (default Priority 2) to use default sett ings
Connect system circulator to corresponding output.
Use isolation relays if connecting 3-wire zone valve end
switches to the inputs.
16 Water chiller
17 Check valve
18 Strainer
19 Balancing valve
20 Make-up water supply
21 Primary/secondary connection (tees no more than 8 pipe diameters apart)
24 System supply and return immersion sensors, at least 6 pipe diameters (but no
more than 3 feet) from boiler connection tees.
25 Systems using high-head pumps may require a bypass pressure regulator to prevent
damage to control valves.
26 External drain/blowdown valve, when used.
31 Install a union on the boiler supply and return connections as close as possible
to the boiler to allow disconnection for service when required.
23