Generator Installation in Portland & Southern Maine

The generator itself gets the attention, but the automatic transfer switch (ATS) is what makes it safe and automatic. When utility power drops, the ATS disconnects your house from the grid before it connects the generator — which is what stops your generator from back-feeding power onto utility lines a repair crew might be touching. A generator wired without a proper transfer switch is a genuine hazard to line workers, and it's not legal to install that way.

Once utility power returns, the ATS switches back automatically and shuts the generator down after a brief cool-down run.

A whole-house generator is sized to run everything at once, including central air and an electric range. Most Maine homes don't need that — we size to the loads that actually matter during an outage: the heating system's controls and circulator or blower, the well pump, the refrigerator, some lighting and outlet circuits, and often a sump pump. A managed-load or partial-house unit covering those circuits costs meaningfully less than whole-house and covers what an outage actually threatens: heat, water, and food safety.

Fuel source is part of the sizing conversation too — propane and natural gas units start automatically and run as long as fuel is supplied, while diesel units need to be refueled manually during an extended outage.

Every standby generator runs a short self-test on a schedule you set — typically weekly — cycling the engine for several minutes without transferring the load. This isn't a novelty feature; it's what keeps the oil circulating, the battery charged, and the fuel system from gumming up, so the unit actually starts when you need it during a real outage. We set this schedule during installation and it's worth confirming it's still running after any power blip resets the controller's clock.

Generac Evolution and Sync Controllers

Generac's Evolution and Sync controllers don't make you decode a number — the LCD screen spells the alarm out in plain English, and the unit logs it so it's still there if you missed the moment it happened. These are the ones we see most on service calls.

Kohler (Rehlko) RDC2 and DC Controllers

Kohler's home standby line — sold under the Rehlko name since the company's 2025 rebrand — uses the same plain-language approach on its RDC2 and older DC controllers, with the display distinguishing a warning you can keep running through from a fault that shuts the unit down.

Champion's standby units use LED status indicators, and on the models with a digital display, a numeric fault code cross-referenced in that model's owner's manual. Champion doesn't publish one universal code list across its whole standby lineup, so we match the exact model before quoting a code's meaning rather than guess from a similar-looking unit.

Standby generators have manufacturer-specified clearances from windows, doors, and fresh-air intakes — commonly measured in feet, not inches — because exhaust carbon monoxide has to be kept away from anywhere it could enter the house. Local fire and building codes add their own setback and permit requirements on top of the manufacturer's spec. We handle the siting, the concrete or composite pad, the gas or propane hookup, and the electrical permit and inspection together, since all four have to agree with each other.