Zoning With Zone Valves - Weil-McLain Ultra Commercial Installation And Start-Up Manual

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Install water piping

Zoning with zone valves

1. Connect boiler to system as shown in
zoning. The primary/secondary piping shown ensures the boiler
loop will have sufficient flow. It also avoids applying the high head
of the boiler circulator to the zone valves.
2. When using a closed-type expansion tank, connect the expansion
tank and make-up water piping as shown in Figure 7, page 15.
3. Connect DHW (domestic hot water) piping to indirect storage
water heater as shown.
If DHW input is priority 1: With factory default, on a
call for DHW heating, the U-Control turns circulator 1
(DHW) and circulator 4 (boiler) ON and turns circula-
tors 2 and 3 OFF (so there is no space heating during
DHW operation). For the system shown in Figure 8, you
can set the U-Control to turn the boiler circulator off
during DHW heating. It is not needed. (The flow/check
valve shown on the boiler outlet piping prevents gravity
circulation in the boiler loop.)
4. Controlling the circulators
a. The U-Control can control up to four circulators (boiler cir-
culator and three others). Refer to Field wiring, beginning on
page 51, for instructions on wiring to circulators.
b. The factory default settings are: DHW circulator as Circula-
tor 1, system circulator as Circulator 2, and boiler circulator
as Circulator 4. See Field wiring instructions, beginning on
page 51, for details. (
1 Ultra boiler
2 Indirect water heater (DHW), if used
3 Boiler relief valve (see page 13 for piping details)
4 Relief valve discharge piping (see page 13 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 15 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
12 Boiler circulator
13 Zone valves, typical
20 Make-up water supply
21 Primary/secondary connection
16
-
FIRED WATER BOILER
(continued)
Figure 8 when zone valve
Legend — Figure 8
— Boiler Manual
Zone valve zoning plus optional DHW
piping
24 Strap system supply and return sensors to lines as shown, 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 Boiler drain valve, ¾" or larger
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.
Items supplied with boiler
Items supplied by others
Use at least the following pipe sizes on all boiler
NOTE 1:
loop piping (connecting boiler to and from the
primary/secondary connection, item 21). Pipe sizing is based on a temperature
rise of 30°F, corresponding to the recommended maximum flow rate. Use only
primary/secondary piping as shown. Failure to follow these guidelines could
result in system problems.
Part number 550-100-086/0809