Whole-Home Surge Protection, and Why the 2020 NEC Requires It on New Services

A lightning strike nearby, a utility switching event or a tree on the line can send a spike of voltage through your home’s wiring in a fraction of a second. Today’s homes are full of electronics that don’t tolerate that well: HVAC control boards, refrigerators, washers, smart thermostats, TVs and the electronics inside an EV charger. A whole-home surge protector at the panel is the first line of defense.

What a Surge Is, and Where It Comes From

A surge is a brief spike in voltage far above the normal 120 or 240 volts. Big ones come from lightning and utility events. Smaller, frequent ones come from inside the house when motors and compressors switch on and off. The small ones rarely do instant damage, but over time they wear down electronics.

How Whole-Home Surge Protection Works

A surge protective device (SPD) mounts at or in your main panel. When voltage spikes, it diverts the excess energy to ground before it reaches your circuits. It protects everything wired to the panel, including hardwired equipment that a plug-in strip can’t reach, like your HVAC system, water heater controls, well pump and ceiling fans.

It works best as part of a layered approach:

• Whole-home SPD at the panel to stop large surges coming in from outside
• Point-of-use surge strips for computers, TVs and networking equipment
• Good grounding and bonding, because a surge protector is only as good as the ground it sends energy to

It’s Now Required on New and Replaced Services

The 2020 National Electrical Code, which Virginia enforces through its statewide building code, requires a surge protective device on the service of a home when the service is installed or replaced. So if you’re getting a panel or service upgrade, surge protection is part of the job. For existing homes, it isn’t required, but it’s one of the most cost-effective upgrades you can make.

What a Surge Protector Can’t Do

• It can’t stop a direct lightning strike to your home. Nothing in the panel can. Lightning protection systems on the structure are a separate specialty.
• It wears out. Each large surge uses up some of its capacity. Most units have an indicator light; check it after storms and replace the unit when it shows it’s done.
• It doesn’t fix wiring problems like loose neutrals, which can cause damaging voltage swings. If lights brighten and dim, have the wiring checked.

Which Homes Benefit Most

• Homes on rural or overhead lines, which see more surges
• Homes with a well pump, heat pump or other expensive motor-driven equipment
• Homes with an EV charger, solar, battery storage or a generator
• Anyone who has lost an appliance or HVAC board to a storm

Want to protect your home’s equipment? Book a visit on our booking page and we’ll install surge protection and check your grounding while we’re there.

Frequently Asked Questions

Is a whole-house surge protector worth it?

For most homes, yes. It protects hardwired equipment like HVAC and appliances that plug-in strips can’t, and it usually costs less than one repair to an HVAC control board.

Is a surge protector required in Virginia?

Under the 2020 NEC, which Virginia enforces, a surge protective device is required when a home’s service is installed or replaced. It isn’t required to be added to an existing service.

Do I still need surge strips?

Yes, for sensitive electronics. The whole-home device handles large surges coming in; strips add protection at the device.

How long does a whole-home surge protector last?

It depends on how many surges it absorbs. Check its status light, especially after storms, and replace it when it indicates it’s no longer protecting.

Why Homeowners Choose Progress and Heritage

Our licensed, insured, background-checked electricians install surge protection correctly, check your grounding and bonding, and make sure the device suits your panel. We serve Lynchburg, Roanoke, Danville, Martinsville and the surrounding counties. See our home technology and power solutions.