Weil-McLain SVF 1500 Manual page 22

SVF
™
Series 1
Commercial Condensing Gas-Fired Water Boiler — Boiler Manual
Install water piping
Radiant Heating — Zone valve zoning –
secondary (Shown with optional DHW piping)
TM
SVF
Th e boiler is ideal for use in radiant heating. Th e unique heat exchanger
design allows it to work well even in condensing mode. Th ere is no need to
regulate boiler return water temperature in radiant heating applications. Th e pri-
mary/secondary 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. Apply this confi guration for typical radiant heating applications.
2. Size the system piping and circulators to provide the fl ow and pressure
drop needed.
3. 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 .
High limit in system piping
1. Add the recommended high limit control ( Figure 19 , item 22) to help ensure
supply water temperature will not exceed the maximum allowable for the
radiant system.
2. Wire the limit control to either the manual reset or automatic reset external
limit circuit of the Control.
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 simultaneously
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
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
11 Purge/drain valves
22
(continued)
primary/
See Figure 19 .
pipe size shown in Figure 11, page 16
Legend — Figure 19
Figure 19
Typical radiant heating system piping plus
optional DHW
2. Th e factory default sett ings are: all three inputs are set up for Space
Heating ( Priority 2) . Each input correlates to its respective circu-
lator 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 WMCR zone Circ
controller.
Connect zone valve end switches to a Space Heat-
ing 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.
12 Boiler circulator
13 Zone valves, when used (zoning may also be done using manifold-mounted valve
actuators).
20 Make-up water supply
21 Primary/secondary connection (tees no more than 8 pipe diameters apart)
22 Optional high limit temperature control, set to protect radiant tubing.
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.
Part number 550-100-250/0819