Why Your New Hampshire Home Needs Whole-House Surge Protection

Homes have changed.

Today, even everyday household equipment depends on electronic controls, circuit boards, sensors, variable-speed motors, Wi-Fi connections, and digital displays.

Your heating system may have an electronic control board. Your refrigerator has one. So do many water heaters, washing machines, ranges, televisions, well systems, heat pumps, mini-splits, garage door openers, and smart-home devices.

That makes modern homes more convenient and efficient.

It also means there are more electronic components throughout the home that can be affected by electrical surges.

For New Hampshire homeowners, whole-house surge protection can provide an important layer of defense against voltage spikes caused by storms, utility activity, power restoration, and electrical equipment inside the home.

A Power Surge Does Not Have to Be a Lightning Strike

Most people hear “power surge” and picture lightning hitting the house.

That can happen, but it is not the only concern.

Electrical disturbances can also occur during utility switching, some power-restoration events, equipment failures, or when large electrical loads cycle on and off.

Some surges are large enough to cause immediate damage.

Others may be relatively small and go completely unnoticed.

Either way, many modern electronic controls can be sensitive to voltage transients that older, simpler equipment did not rely on in the same way.

Your House Has More Electronics Than You Think

Twenty or thirty years ago, many major home systems were relatively simple.

A furnace might have used basic relays and controls. An air conditioner used a straightforward compressor, capacitor, and contactor. Appliances relied much more heavily on mechanical switches and timers.

Modern equipment looks very different.

Consider what may contain sensitive electronics in an average New Hampshire home:

• heat pumps and mini-splits
• boilers, furnaces, and water heaters
• refrigerators and modern kitchen appliances
• washing machines and dryers
• televisions, computers, and networking equipment

Add smart thermostats, security systems, garage door openers, well controls, EV charging equipment, and home automation, and the amount of electronic equipment adds up quickly.

Protecting the electrical system now means protecting much more than a few televisions and computers.

Heat Pumps Are a Good Example of the Change

Modern heat pumps illustrate why surge protection has become increasingly important.

A high-efficiency variable-speed heat pump contains sophisticated electronics that continuously control compressor speed, fan operation, temperature, communication between components, and system diagnostics.

Those electronics are part of what makes today’s heat pumps so efficient.

They can also be expensive to replace.

A significant electrical event may damage an inverter board, control board, variable-speed motor, or other electronic component while leaving much of the rest of the equipment physically intact.

That can turn what looks like a minor electrical problem into a costly HVAC repair.

What Does Whole-House Surge Protection Do?

A whole-house surge protective device, or SPD, is usually installed at or near the home’s main electrical panel.

During normal operation, it essentially sits in the background.

When a short-duration voltage spike occurs, the SPD reacts quickly to limit the voltage reaching downstream equipment and divert surge current away from sensitive electronics.

That gives the electronics throughout the house another layer of protection.

Think of it as protection at the front door of your electrical system.

It cannot prevent every electrical problem, but it can reduce exposure to the types of transient voltage spikes it is designed to handle.

Why Plug-In Surge Strips Are Not Enough

Power strips with surge protection can still be useful for computers, televisions, and other plug-in electronics.

But plug-in surge protectors primarily protect the equipment connected to them. They do not provide whole-house protection for hardwired systems such as:

• central air conditioning systems
• heat pumps
• furnaces and boilers
• electric water heaters
• well pumps

A whole-house SPD protects the electrical system at a much earlier point, helping protect both plug-in and hardwired equipment.

For particularly sensitive or expensive systems, an electrician may also recommend additional surge protection closer to the individual piece of equipment.

Layered Protection Can Make Sense

For some homes, surge protection works best as a layered system.

The first layer is the whole-house SPD at the main electrical panel.

A second layer may be installed near particularly valuable equipment, such as a variable-speed heat pump.

That arrangement gives incoming electrical disturbances more than one point of protection before they reach sensitive electronics.

A homeowner who recently invested in a new heat pump, mini-split system, well system, generator, or other major electrical equipment may want to discuss whether dedicated protection makes sense in addition to whole-house protection.

It is also worth noting that a panel-mounted SPD protects the home’s electrical power system. Sensitive equipment connected to cable, communication, or other external wiring may need additional protection.

What Surge Protection Does Not Protect Against

It is important to understand that surge protection does not solve every power-quality problem.

A standard SPD is designed primarily for short-duration voltage spikes.

Different equipment or electrical repairs may be necessary to address problems such as:

• prolonged low voltage
• sustained excessive voltage
• damaged or loose electrical connections
• certain neutral problems
• repeated breaker trips

If lights frequently dim or brighten, appliances behave strangely, breakers repeatedly trip, or electronic equipment keeps failing, simply adding a surge protector may not address the underlying issue.

Those symptoms deserve an electrical inspection.

What the Electrical Code Says About Surge Protection

Surge protection has become important enough that it is now part of the National Electrical Code requirements for dwelling-unit services.

The 2023 National Electrical Code requires surge protection for electrical services supplying dwelling units under NEC 230.67. The device must be a listed Type 1 or Type 2 SPD and meet the minimum performance requirements specified by the code.

New Hampshire incorporated the 2023 NEC into its state building code effective July 1, 2026.

That does not necessarily mean every existing New Hampshire home must immediately add surge protection. Exactly when the requirement applies depends on the type of electrical work being performed and the applicable code enforcement authority.

For homeowners with an older electrical service, a licensed electrician can determine whether surge protection is already present and whether an upgrade makes sense.

New Hampshire Storms Add Another Reason to Think About It

New Hampshire homes see plenty of conditions that can challenge the electrical system.

Summer thunderstorms can bring lightning and downed lines. Winter storms can cause outages from snow, ice, and falling trees. Power may shut off and return several times during a major weather event.

Utility switching and some power-restoration events can create electrical disturbances, which is another reason surge protection can be valuable in a storm-prone area.

Check Your Surge Protector After Major Electrical Events

Surge protective devices do not necessarily last forever.

Many use components designed to absorb or redirect electrical energy and may eventually reach the end of their protective life.

Most professionally installed devices include an indicator light showing whether protection is still active.

After a major storm, outage, or known electrical event, take a quick look at the device if it is safely visible.

If the protection indicator is no longer showing normal operation, contact an electrician.

Protecting More Than One Appliance

The biggest reason to consider whole-house surge protection is simple.

You are not protecting one television.

You are protecting an entire collection of increasingly expensive electronics spread throughout your home.

Your HVAC system alone may contain several electronic boards and variable-speed motors. Add your appliances, computers, entertainment equipment, water systems, security equipment, and smart-home technology, and the value connected to your electrical system can quickly reach tens of thousands of dollars.

A properly selected and professionally installed whole-house surge protector provides one additional layer of protection for all of it.

Is Whole-House Surge Protection Right for Your Home?

It is especially worth discussing if your home has:

• a modern heat pump or ductless mini-split
• recently upgraded appliances
• a private well or electronic water equipment
• extensive smart-home or entertainment electronics
• frequent outages or storm-related power problems

Even older homes can benefit, particularly when new high-efficiency equipment has been added over time.

Protect the Systems Your Home Depends On

Modern homes depend on electronics for comfort, communication, cooking, water, security, and everyday convenience.

That makes electrical protection more important than it used to be.

Whole-house surge protection will not prevent every possible electrical failure, but it can provide an important first line of defense against damaging voltage spikes throughout the home.

Al Terry Plumbing, Heating, Air Conditioning & Electric has been serving New Hampshire homeowners for 50 years. Because our team works with both HVAC and electrical systems, we can help evaluate your home’s electrical protection, identify high-value equipment that may need additional protection, and determine whether whole-house surge protection makes sense for your property.