The EnergyLogic furnace wiring and oil schematic is section 10.1 of the heater manual and is published as a standalone one-page PDF, Furnace System Wiring Diagram. Because it is a drawing rather than text, the diagram itself lives in the PDF — download it below. This page covers the electrical facts that surround it: the power the furnace requires, the three connections you actually make during installation, and what each terminal on the primary control does.
Written and reviewed by the NuEra Heat service team
Written from section 10.1 and the electrical requirements sections of the EnergyLogic heater installation and operation manual, plus our own installation notes. NuEra Heat has been selling, servicing, and stocking parts for waste oil heating equipment for over 30 years across Alaska and the Pacific Northwest. About NuEra Heat — questions on any step, call 1-800-347-9575.
Every EnergyLogic furnace is supplied through a dedicated, hard-wired 115 VAC / 60 Hz circuit with a 25 amp maximum circuit breaker, using copper conductors only. Check local codes before you plan the run. A wiring diagram is provided in the appendix of the installation manual, and the same drawing is published separately as the Heater Schematic PDF linked above.
Plan the routing before installation: your building layout has to allow safe routing of the electrical wiring to the furnace, and the furnace is designed to be installed above head height or in a manner that restricts access.
Mount the thermostat five feet (1.5 m) above the floor on an interior wall, out of the path of warm or cold air. Do not mount it on a cold exterior wall, do not mount it on the furnace cabinet, and do not let it hang by the wiring harness. Pass the wire harness through the large opening at the center of the wall plate before mounting.
On the standard thermostat, the black wire lands on the (R) terminal (24 VAC power) and the red wire lands on the (W) terminal (heat relay). Route the thermostat wire to the burner and plug the cable connector into the receptacle at the burner wiring box. If you are installing an EnergyLogic low fuel cut-off switch, or a Top Suction Kit with an integrated low fuel cut-off, the thermostat circuit passes through that switch — the schematic shows both the with-cutoff and without-cutoff arrangements. The SmartStat (black) thermostat follows the instructions in its own package instead.
With power shut off and locked out, run flexible metal conduit carrying white, orange, and green wires, NEC size 14 AWG, from the cabinet wire box to the fuel pump housing, using the hole provided on the right side of the housing. Using the female crimp-on terminals provided, connect the orange wire to one pump motor male terminal and the white wire to the other — it does not matter which is which — and connect the green ground wire to the ground screw on the middle housing bracket.
If you are making your own harness, the cabinet wire box terminal block is labeled: orange to ORG, white to WHT, green ground to GND. Insert stripped ends into the terminal holes and tug gently to confirm each connection is secure.
Have a certified electrician install a wall- or ceiling-mounted junction box near the furnace cabinet — ideally switchable with a lock-out feature — fed from the building service panel on a dedicated 115 VAC single-phase circuit with a 25 amp maximum breaker per UL.
Run flexible metal conduit with white, black, and green wires, NEC size 12 AWG from the cabinet wire box to that junction box, using the knock-outs on the box. With wire nuts, join black (load) to black, white (neutral) to white, and green (ground) to the bare copper wire in the junction box. On a self-made harness the cabinet terminal block is labeled BLK, WHT, and GND.
Burner operation is governed by the primary control, which is pre-programmed and not adjustable. Two terminal pairs on it show up constantly in service work and on the schematic:
Those jumpers are used deliberately during priming and testing — see the cad cell testing guide for the resistance checks that go with them.
Every document below is a direct download from the NuEra Heat support library:
For electrical components themselves — primary controls, ignition transformers, wiring box assemblies, burner cords, thermostats — use the interactive explosion charts to identify the part on a diagram and jump to it in the store. Free phone tech support is available at 1-800-347-9575.
