How a standby generator works
A standby generator is permanently installed outside the house, like a central air condenser, and connected to both your electrical system and a fuel supply. It is not something you wheel out and start.
When the transfer switch detects that utility power has failed, it signals the generator to start, waits for it to stabilise, then transfers your circuits over. When utility power returns and holds, it transfers back and shuts the generator down.
What that means in practice
- Power restores automatically, whether or not you are home
- Heating, refrigeration, and sump pumps keep running
- No cables, no fuel cans, no running anything in the cold
- The generator self-tests weekly to confirm it will start
- Nothing is ever back-fed into the utility network
Sizing: whole-home or essential circuits?
This is the decision that sets the budget, and it is worth being honest about. A true whole-home unit runs everything simultaneously, including central air and an electric range. That is a large machine.
Many households are better served by a smaller unit covering essential circuits: heating, refrigeration, well or sump pump, lighting, internet, and a few outlets. The difference in cost is significant and the difference in comfort during an outage is often small.
- Heating system, including the blower on a gas furnace
- Refrigeration and freezers
- Sump pump and well pump, critical in this region
- Lighting and general outlets in the rooms you use
- Internet, networking, and home office equipment
- Medical equipment, which should always be on the essential list
- Central air conditioning, usually the reason to go larger
Load management can shrink the generator
Load management modules shed large loads such as air conditioning when the generator is near capacity, then restore them. That often lets a smaller, cheaper unit cover more of the house than its rating suggests.
The transfer switch
The transfer switch is the part that matters most for safety. It ensures your house is connected to either the utility or the generator, never both.
That is not a formality. Back-feeding power onto a utility line that crews believe is dead can kill someone working on it. This is the single strongest reason generator installation is not a do-it-yourself job.
- Automatic transfer switch, which needs no action from you
- Whole-panel or essential-circuits subpanel configuration
- Load management to shed and restore large loads
- Correct interlock so utility and generator can never connect together
- Sized and rated to your service, not generically
How the installation runs
- 1
Load assessment and site visit
We work out what you want running and where the unit can sit. Placement is constrained by clearances from windows, doors, and property lines, and by how far the fuel and electrical runs have to travel.
- 2
Fixed quote and permits
The quote covers generator, transfer switch, pad, electrical, and fuel connection. We pull the electrical permit, and coordinate the gas permit and fitter where the fuel work is not ours.
- 3
Installation
Pad set, unit placed, transfer switch installed, electrical and fuel connected. Most residential installations take two to three days across the trades involved.
- 4
Commissioning and inspection
We start the unit, simulate an outage, verify the transfer both ways under load, and set the weekly self-test. Then the inspector signs off and we walk you through operation.
Natural gas or propane
Most homes in this area run standby generators on natural gas where a supply exists, and propane where it does not.
Natural gas means no tank and no refuelling, but it depends on the gas network staying up. Propane needs a tank sized for the runtime you want, and the tank has to be refilled, but it is independent of any network.
- Natural gas: no tank, unlimited runtime while the network holds
- Propane: independent supply, but sized and refilled by you
- Meter or regulator capacity may need upgrading for gas
- Tank size drives how many days of runtime you get
- Fuel line sizing is set by distance and the unit's demand
Permits, placement, and inspection
Generator installation needs an electrical permit and, in most cases, a gas permit. Both are inspected. Some towns also have noise ordinances or setback requirements that affect where the unit can sit.
Placement is governed by clearances from openings, combustible surfaces, and property lines. We confirm those on the site visit rather than discovering a problem at inspection.
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Frequently asked questions
- How big a generator do I need? +
- It depends on what you want running at once. A true whole-home unit that runs central air and an electric range is large. Many households do better with a smaller unit on essential circuits plus load management. We size it after listing what actually matters to you.
- How fast does it come on? +
- Typically within seconds of the transfer switch detecting the outage. There is a brief interruption while the generator starts and stabilises, so sensitive equipment still benefits from its own battery backup.
- How long does installation take? +
- Most residential installations take two to three days once permits are in hand, allowing for the electrical work, the pad, and the fuel connection. Lead time on the unit itself is usually the longer part.
- Natural gas or propane? +
- Natural gas if you have a supply, since there is no tank and no refuelling. Propane where there is no gas line, or where you want a fuel source independent of the network. Tank size then determines runtime.
- Will it run air conditioning? +
- It can, but air conditioning is usually what pushes a unit into a larger size. Load management is often the better answer: it sheds the AC when the generator is near capacity and restores it when there is headroom.
- Is it noisy? +
- Modern standby units are considerably quieter than portable generators, but they are not silent, and they self-test weekly. Some towns have noise ordinances or setback rules, which we check as part of placement.