Crown Boiler FWZ Series, Installation Instructions Manual

Page: 29 / 56

27
X Wiring
WARNING
• All wiring and grounding must be done in accordance with the authority having jurisdiction
or, in the absence of such requirements, with the National Electrical Code (ANSI/NFPA 70).
• Disconnect electrical power to the boiler and heating system before servicing. Positively
assure that no voltage is present. Lock electrical boxes to prevent someone from
inadvertently restoring power before the heating system is safe to operate.
• Never defeat or jump out safety devices.
• Protect each boiler circuit with a properly sized over-current protection device.
• Make electrical connections carefully according to the boiler’s wiring diagram and
instructions.
• Wire additional field supplied safety limits, such as low water cutoffs and temperature limit
devices, in series with the 120V circuit used to power the boiler. Do not alter the boiler’s
factory wiring when adding an additional limit device.
1) 120 Volt Wiring - The boiler should be provided with its own 15A branch circuit with fused disconnect. 120VAC power con -
nections are made inside the Hydrolevel 3250-Plus hot water boiler control as follows (also see Figures. 10.0 and 10.1):
• Hot (“black”) - Terminal “L1”
• Neutral (“white”) - Terminal “L2”
• Ground (“green” or bare) - Ground screw on case of 3250-Plus.
The heating circulator is factory wired to the 3250-Plus circulator connections or the boiler is provided with a flexible conduit
“whip” that is to be wired to the 3250-Plus circulator connections. If the circulator is not already wired to the control, connect
it as follows:
• Circulator “Hot” - Black wire lead from “whip” to C1
• Circulator “Neutral” - White wire lead from “whip” to C2
2) Low Voltage Connections – Low voltage field connections are located as shown in Figure 10.0 and 10.1 and are as follows:
• T-T - Connect to a 24 volt heating thermostat or other “dry contacts” (such as a zone panel end switch) that close upon
a call for heat. Follow thermostat manufacturer’s instructions. To insure proper thermostat operation, avoid installation
in areas of poor air circulation, hot spots (near any heat source or in direct sunlight), cold spots (outside walls, walls
adjacent to unheated areas, locations subject to drafts). Provide Class II circuit between thermostat (or zone controls) and
boiler.
3) Adding a Second Circulator Zone - The control provided on this boiler can be used to control a second heating or DHW
circulator zone. If this is done, make the following 120VAC connections in addition to those described above (also see Figure
10.0):
• Connect a 120VAC heating or DHW thermostat for the second zone between ZC and ZR.
• Connect the DHW circulator or the second heating zone circulator between ZR and L2.
See Part XII of this manual for information on configuring the control to respond properly to the DHW or second heating
zone circulator.