GSA
Gas-Fired Steam Boilers –
Boiler Manual
13
Part Number 550-110-738/0703
For your safety, 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.
Wiring must be N.E.C. Class 1.
If rollout thermal fuse element wire supplied with boiler
must be replaced, type 200 °C wire or equivalent
must be used. If other original wiring 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 edition.
Electrical installation must comply with:
1. National Electrical Code and any other national, state, provincial
or local codes or regulations.
2. In Canada, CSA C22.1 Canadian Electrical Code Part 1, and
any local codes.
Figure 11
Field wiring connections — service switch and thermostat (or end switch) provided by installer
6
Field wiring
Wiring connections
Boiler is shipped with controls completely wired, except spill switch
and vent damper. See wiring diagram on page 17 for standing pilot
ignition boiler.
Thermostat
1. Connect thermostat as shown on wiring diagram on boiler.
2. Install on inside wall away from influences of drafts, hot or cold
water pipes, lighting fixtures, television, sunrays or fireplaces.
3. If thermostat has a heat anticipator, set heat anticipator in
thermostat to match power requirements of equipment
connected to it. If connected directly to boiler, set for 0.4 amps.
For other devices, see manufacturer’s specifications. Wiring
diagram on boiler gives setting for control module and gas valve.
Also see instructions with thermostat.
Junction box
1. Connect 120 VAC power wiring (Figure 11). A separate electrical
circuit with a fused disconnect switch (15 amp. recommended)
should be used for the boiler.