Weil-McLain WM97+100 Manual page 68

WM97+ Series 2
Field wiring
Line voltage wiring (120 VAC)
Make the following line-voltage connections, some of which depend
on your system and how the WM97+ control will be programmed.
The callouts below refer to Figure 78.
A
1. Provide and install a fused disconnect or service switch (15-ampere
rated recommended) as required by applicable codes.
2. Connect minimum
boiler line voltage terminal strip as shown in Figure 78.
3. If possible, provide a surge suppressor in the supply power line.
This will reduce the possibilities of WM97+ control damage due
to line surges.
B
1. Ground wires must be terminated with
terminals.
2. Connect ground wires to the grounding block, item .
C
1. The WM97+ control provides 120VAC outputs for up to three
zones.
The WM97+ control default setting is for three space
heating zones. The control settings must be changed to
operate on DHW.
2. Control options require that DHW tanks be controlled from Zone 1
if domestic water priority is required.
3. ALWAYS connect the DHW circulator to Zone 1 if domestic prior-
ity is required. This can be done if the DHW tank is piped to the
DHW connections out the bottom of the WM97+ or if the DHW
tank is piped as a separate zone in a circulator-zoned system.
4. Zone 1 can be used to provide 120 VAC to a zone circulator if
DHW is not used.
D
1. Use the Zone 2 output to:
a. Provide 120 VAC to a system circulator (such as on a zone valve
system with system circulator).
b. Provide 120 VAC to a zone circulator.
c. Provide 120 VAC to a relay coil, with the relay contact used to
enable/disable another device.
2. The WM97+ control will activate Zone 2 if the Zone 2 thermo-
stat or input device calls for heat, after DHW heating (if used) is
satisfied.
E
1. Same as Zone 2. This output is not used for zone valve systems.
Activating system zoning controls
1. To activate system controls (zoning panels, building management
controls, etc.):
a. Use the output from Zone 1 to directly control the DHW
circulator. Connect the Zone 2 output to an isolation relay.
b. Use the relay contact to enable/disable the system space heat-
ing controls.
c. This allows the WM97+ control to provide domestic prior-
ity and outdoor reset control of supply water temperature to
maximize boiler efficiency.
– 68 –
-
GAS FIRED WATER BOILER
(continued)
power wiring to WM97+
female spade
— Boiler Manual
WM97+
connections (120VAC)
— CIRC1 and ZONE1 cir-
cuits are dedicated to the Weil-McLain
Aqua Logic Water Heater and cannot be
used for other purposes. See Aqua Logic
(CWH) manual for details.
For circulators with higher amp rat-
ings, you must install a circulator relay
or starter to provide line voltage to the
circulator. For circulators rated over 2.2
amps, connect only the circulator relay
or starter coil to the WM97+ circulator
terminals.
ure 77, page 67 for wiring connection
locations. See Figure 80, page 70 for the
complete schematic wiring diagram. See
Figure 81, page 71 for the complete ladder
wiring diagram.
Part number 550-142-204/0117
input and output
—
.
— See Fig-