Surge Protection · Franklin County & St. Louis, MO
Missouri thunderstorms, downed lines, and Ameren grid switching all send voltage spikes into your home — and a single surge can fry HVAC boards, refrigerators, EV chargers, and every piece of electronics on the circuit. A whole-house surge protector mounts at your panel and clamps those spikes before they reach anything inside. CAS Electric installs Type 2 SPDs (Eaton, Siemens, Square D, Leviton) across Franklin County and Greater St. Louis — usually in under an hour.
Most whole-house surge protector installs in the St. Louis area run $300–$600 installed depending on the SPD model and panel brand. Devices typically carry a 5–25 year warranty plus a connected-equipment warranty from the manufacturer.
We look at your panel brand, available breaker space, and grounding to pick the right Type 2 SPD for your home.
You get a written price for the device + install — no hourly meter running.
We mount the SPD next to your main breaker, land it on a dedicated 2-pole breaker, verify grounding, and test the status indicator.
We show you the status LEDs, explain what to do if it ever trips, and leave you with the warranty paperwork.
Most installs in Franklin County and the St. Louis area run $300–$600 all-in. That covers a quality Type 2 SPD (Eaton, Siemens, Square D, or Leviton), a dedicated 2-pole breaker, and the labor to mount and wire it at your main panel. We give a flat written quote before starting.
Yes — for layered protection. The whole-house unit clamps the big spikes at the panel, but sensitive electronics (TVs, computers, gaming consoles) benefit from a point-of-use surge strip as a second line of defense. We recommend running both.
No device stops a direct strike to your home — that's why you carry homeowner's insurance. What a whole-house SPD does stop is the much more common stuff: nearby lightning that induces a surge on the lines, downed-line events, and Ameren grid-switching transients. Those are what kill HVAC boards and appliances.
Most quality SPDs last 5–10 years under normal grid conditions, longer if your area doesn't see heavy storms. Every unit we install has status LEDs — when they change color, it's time to replace the device. Many models also carry a manufacturer warranty on the connected equipment.
Not usually. As long as you have two adjacent breaker slots open and your panel is in good shape, we can add a Type 2 SPD. If your panel is full, undersized, or a problem brand (Federal Pacific, Zinsco), we'll talk through whether a panel upgrade makes sense first — but most homes are ready to go as-is.
Licensed, insured, owner-operated. We respond to all estimates within 1 business day.