A surge protector is a device that shields your electrical equipment from voltage spikes — brief, intense surges of electricity that can damage or destroy sensitive electronics, appliances, and HVAC systems. Surge protectors range from simple power strips with built-in protection to whole-home surge protection devices installed at your electrical panel that guard every circuit in the house simultaneously.
What Causes Power Surges
Most people associate power surges with lightning strikes, and while a direct or nearby lightning strike can send a devastating voltage spike through your home’s wiring, the majority of surges are internal and much more mundane. When large motors and compressors — refrigerators, air conditioners, HVAC systems, sump pumps — cycle on or off, they briefly disrupt the voltage on the circuits they share. These small surges happen dozens of times a day in a typical home and gradually degrade the sensitive electronics inside modern appliances, smart TVs, computers, and smart home devices over months and years.
External surges also arrive through the utility grid during switching operations, equipment failures, and downed lines. Colorado’s frequent summer thunderstorms and lightning activity make external surge risk higher than in many parts of the country — the Front Range is one of the most lightning-active regions in the United States.
How Surge Protectors Work
Most consumer surge protectors use metal oxide varistors (MOVs) — components that conduct excess voltage away from the circuit and to ground when voltage exceeds a safe threshold. The MOV absorbs the surge rather than letting it reach your equipment. MOVs have a finite capacity measured in joules — once that capacity is used up by absorbed surges, the MOV can no longer protect. Many strip-style surge protectors offer no indication when this has happened, which is why whole-home protection at the panel level is the more reliable long-term solution.
Whole-Home Surge Protection vs. Point-of-Use Strips
Point-of-use surge protectors (power strips with built-in surge protection) protect the devices plugged directly into them. They’re portable, inexpensive, and appropriate for desktop computers, entertainment systems, and home office equipment. Their limitations are real, though: they don’t protect equipment that’s hardwired (HVAC systems, water heaters, built-in appliances), they can’t stop a large surge from damaging equipment on other circuits, and their MOVs degrade silently over time.
A whole-home surge protector installed at your main electrical panel addresses these limitations. It intercepts surges before they reach any circuit in the house, protects hardwired equipment including your HVAC system and appliances, and is rated for a far higher joule capacity than any power strip. For complete protection, the industry recommendation is a two-tier approach: a whole-home device at the panel plus point-of-use protectors at sensitive electronics.
Why HVAC Protection Matters in Colorado
Modern HVAC systems — heat pumps, variable-speed furnaces, smart thermostats, and high-efficiency air conditioners — contain sophisticated circuit boards and electronics that are far more vulnerable to voltage spikes than older single-stage equipment. A surge that a 1990s furnace would have shrugged off can destroy the control board of a modern variable-speed system, resulting in a repair bill in the hundreds or thousands of dollars. Whole-home surge protection is a modest investment by comparison.
- HVAC control boards and variable-speed motors
- Smart thermostats and home automation hubs
- Refrigerators and dishwashers with electronic controls
- Computers, NAS drives, and home office equipment
- EV chargers and battery backup systems
Installation and What to Look For
Whole-home surge protectors install at your main electrical panel and are wired directly to your service. Installation is straightforward for a licensed electrician and typically takes less than an hour. Look for a device rated by the Underwriters Laboratories UL 1449 standard, with a clamping voltage of 400V or lower and a joule rating appropriate for your home’s exposure. Devices with a built-in status indicator or audible alarm notify you when the protection has been used up and needs replacement.
Done’s electricians can install whole-home surge protection as a standalone service or alongside a panel upgrade or new installation. Visit our smart home and electrical safety page for more information, or explore our panels and wiring services if your surge protection project is part of a broader electrical update.
