Weil-McLain SVF 1500 Manual page 17

SVF
™
Series 1
Commercial Condensing Gas-Fired Water Boiler — Boiler Manual
Install water piping
ZONE VALVE zoning –
(Shown with optional DHW piping)
Th is confi guration is for zone valve systems using a boiler loop connected
as a secondary circuit off of a primary system loop. Th e primary/second-
ary piping shown ensures the boiler loop will have suffi cient fl ow. It also
avoids applying the high head of the boiler circulator to the zone valves.
1. Install a system circulator (supplied by installer) capable of delivering
the proper fl ow and head as shown.
2. 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
page 16 on all boiler loop piping (connecting boiler to and
from the primary/secondary connection, item 21).
secondary piping shown ensures the boiler loop will
have suffi cient fl ow. For other piping methods, see guidelines
starting on page 15 .
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—A DHW tank can be connected as a zone if a DHW
tank is NOT already connected to the boiler. See Advanced Manual
to confi gure Boiler Pump to run during DHW demands and change
TARGET MOD SENSOR to System Supply.
3. System Priority choices:
a. DHW Priority – DHW is priority over space heating. Use Pri-
ority 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 instruc-
tions on wiring to circulators.
2. Th e factory default sett ings are: all three inputs are set up for Space
Priority 2)
Heating ( . Each input correlates to its respective circulator
output. For DHW applications, assign DHW inputs to determined Priority
TM
SVF
1 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)
8 Diaphragm (or bladder) type expansion tank (see page 16
for piping of closed-type expansion tank, if used)
9 Air separator [with automatic air vent only on systems using diaphragm
(or bladder) type expansion tank]
10 Flow/check valves
Part number 550-100-250/0819
(continued)
primary/secondary
See Figure 14 .
pipe size shown in Figure 11,
Legend — Figure 14
Figure 14
Zone valve zoning plus optional DHW piping
(1, 2 or 3). Priority 1 is defaulted to DHW for DHW
tions.
3. For more than 3-zones, use Weil-McLain WMZV zone valve controller.
Connect zone valve end switches to a
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.
11 Purge/drain valves
12 Boiler circulator
13 Zone valves, typical
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.
33 Strainer, recommended.
Priority
applica-
Space Heating
17