Field Wiring (See Figure 52 & Figure 53) - Weil-McLain SlimFit 2 Series Manual

SlimFit ® Series 2
Field wiring
(see Figure 52 & Figure 53)
ELECTRICAL SHOCK HAZARD — For
your safety, turn off electrical power sup-
ply at service entrance panel before mak-
ing any electrical connections to avoid pos-
sible electric shock hazard. Failure to do so
can cause severe personal injury or death.
The installation must comply with: National
Electrical Code and any other national, state,
provincial or local codes or regulations. In
Canada, CSA C22.1 Canadian Electrical Code
Part 1, and any local codes.
Do not use 24V from transformer to power
any external devices that are not listed in
this manual.
Wire entrances
Eight knockouts are provided in the top of the cabinet for
line and low voltage wiring. See Figure 51 for locations.
Installer MUST use a strain relief through jacket knock-
outs. Failure to do so can cause severe personal injury,
death or substantial property damage.
Wiring overview
See details on the following pages for the wiring connec-
tions outlined below:
Required wiring connections
• 120VAC power to boiler; 120VAC power out to boiler cir-
culator; system supply and return temperature sensors.
Connections as needed by systems
• Thermostat, end switch or other inputs for call for heat.
• System zone circulators, valves, relays, etc.
• System circulator, when required.
• Outdoor temperature sensor.
Optional wiring connections
• External limits; Closure switch interlocks (combustion
air damper, flow switch, etc.); 0–10VDC for target
or modulation control; remote alarm; additional heat
demand contact; and communication cables for boiler
networking and/or building management system inter-
face (MODBUS).
Part number 550-100-561/0224
commercial condensing gas
Continued after page 52
- — Boiler Manual
fired water boiler
Wiring must be N.E.C. Class 1. If original wir-
ing 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 – lat-
est edition, and/or the Canadian Electrical
Code Part I, CSA C22.1, Electrical Code.
The boiler when installed, must be electrically
bonded to ground in accordance with the re-
quirements of the authority having jurisdiction
or, in the absence of such requirements, with the
National Electrical Code, ANSI/NFPA 70 – latest
edition, and/or the Canadian Electrical Code
Part I, CSA C22.1, Electrical Code.
Figure 51
Wiring entrances
Line voltage power input
1. Boiler line voltage power — Boiler load: SF1000 —
12.1 Amps; SF1500 — 20.7 Amps; SF2000 — 23.2 Amps.
Provide and install a fused disconnect or service switch as
required by applicable codes. Fuse or breaker rating must
be sized accordingly.
2. Boiler Circ activation circuit — Provide external power for
pump's, 120 VAC/1-phase, size as required for the pump
load. Interrupt pump's hot line with the connections on EP7
screw terminal. Maximum current rating of relay is 10 Amps.
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