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Modulex Light Commercial Series
CHAPTER 4: Installation Instructions
OMM-0158_A
• 6/28/2022 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
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Service Relay Requirement
Upstream of the electrical connection, a service relay is required (not supplied) which, when the
additional electrical safety devices (if any) intervene, shuts down the electrical supply to the on-
off fuel valve fitted on the gas supply circuit, but not to the boiler so as to guarantee the running
of the pump and permit the boiler to cool down
Electrical Requirements
•
No changes may be made to the wiring of the boiler.
•
All connections should be designed in accordance with the applicable regulations.
•
Label all wires prior to disconnection when servicing controls. Wiring errors can cause
improper and dangerous operation.
•
Verify proper operation after operation servicing.
NOTE:
Verify proper operation of the boiler after all servicing operations.
Figure 4-27: 120VAC Power Wiring for Main Electrical Junction Box and Signal
Wiring for Ufly Controller and Boiler Control Module (BCM)
W A R N I N G !
120 VAC cables shall be separated from 24VAC and signal wires, using the two plastic conduits
supplied within the boiler casing LEFT-HAND side panel.