Field Wiring - Weil-McLain WM97-70-CT Manual

WM97+ -
gas fired water boiler

Field wiring

ELECTRICAL SHOCK
HAZARD
— For your safe-
ty, turn off electrical power
supply at service entrance
panel before making any
electrical connections to
avoid possible electric shock
hazard. Failure to do so can
cause severe personal injury
or death.
Figure 74 Field wiring overview
view shown at bottom right is of WM97+70/100 — electrical entrances for WM97+155 are the same)
Line voltage wiring terminals
See Figure 75, page 65 for wiring instructions.
The terminals include the 120-VAC power input and
three 120-VAC outputs (for circulators or other system
devices).
WM97+ wiring
Terminals
All field wiring is made to the two electrical con-
nection panels on top of the boiler. Line voltage,
120 VAC, terminals are on the left. Low voltage,
24 VAC, terminals are on the right.
Wire entrances
Wire entrance knockouts are in the top center of
the electrical enclosure.
As shown in the warning at right,
DO NOT use sharp objects to
punch out the wiring knockouts.
Wires routed under these knock-
outs could be damaged. Use ONLY
a ball peen hammer to punch out
the knockouts.
WM97+ control setup
WM97+ control setup depends on system design
and control intent. See instructions on the fol-
lowing pages.
– 64 –
— Boiler Manual
The installation must com-
ply with:
National Electrical Code
and any other national,
state, provincial or local
codes or regulations. In
Canada, CSA C22.1 Cana-
dian Electrical Code Part 1,
and any local codes.
(see Figure 77, page 67 and Figure 78, page 68 for detailed schematic and ladder wiring diagrams) (top
Wiring must be N.E.C.
Class 1. If original wiring
as supplied with boiler must
be replaced, use only type
105 °C wire or equivalent.
Boiler must be electrically
grounded as required by
National Electrical Code
ANSI/NFPA 70 – latest edi-
tion.
Low voltage wiring terminals
See Figure 76, page 66 for wiring instructions.
The terminals include three thermostat/end switch in-
puts (zones 1, 2 and 3), 24-VAC power for thermostats
(if needed), external limit inputs, alarm contact and
outdoor sensor — see page 133.
Part number 550-142-120/0113