Electrical Panel Red Flags (Federal Pacific, Zinsco, Double Taps)

Your electrical panel is the gray box in the basement, garage or utility closet where every circuit in the house starts. Most people only open it when a breaker trips. It's worth five minutes of your attention, especially in an older house or one you're about to buy.

Safety first: this is a look-only check. Open the panel door, but don't take off the inside cover (the metal plate the breakers poke through). Behind it are live parts that can kill you even with the main breaker off. Taking the cover off is a job for a licensed electrician.

01The brands electricians worry about

Federal Pacific Electric (FPE) Stab-Lok

FPE panels were installed in millions of homes from the 1950s into the 1980s. Look for "Federal Pacific" or "FPE" on the label and "Stab-Lok" on the breakers, which often have a red-orange stripe on the handle. The concern is that some of these breakers may not trip when they should, letting a wire overheat. The U.S. Consumer Product Safety Commission investigated in the early 1980s and closed the case in 1983 without a recall, citing limited budget and uncertain results. Many electricians and home inspectors still recommend replacing them.

Zinsco (and Sylvania-Zinsco)

Zinsco panels were common from the 1950s through the 1970s. The breakers are often in bright colors. The known problem is that breakers can overheat and fuse to the panel's bus bar. When that happens, the breaker looks normal but can't trip.

If your panel is one of these, it isn't an emergency today, but have an electrician look at it and get a quote. If you're buying a house, plan on it. Some insurance companies ask about these panels or won't cover them.

02Look-only red flags on any panel

• Scorch marks, melted plastic or a burnt smell.
• Rust or water stains on the box, or water dripping from the service cable above it.
• A panel that's warm to the touch, or buzzing or crackling sounds.
• Breakers that trip over and over, or a breaker that won't reset.
• Open slots with no breaker and no filler plate, so you can see into the panel.
• No labels, or labels that make no sense ("kitchen?").
• A panel in a bad place: inside a closet full of clothes, in a bathroom, or blocked by shelving. Electricians need clear space in front of it.
• Fuses instead of breakers in an older house, especially with a penny or an oversized fuse in any socket.

03Double taps

A double tap is two wires under one screw on a breaker. Most breakers are made to hold only one wire, so a second wire can work loose, arc and overheat. Some breakers are listed for two wires, and an electrician can tell which. Home inspectors call these out all the time. You'll usually only see a double tap with the cover off, so it's something to look for in an inspection report, not to go hunting for yourself.

04Age and size

Look at the label for the panel's amp rating. A lot of older homes have 60- or 100-amp service. If you're adding an EV charger, a heat pump, a hot tub or a big shop, an electrician may tell you to upgrade.

05When to call an electrician

Any of the red flags above, any FPE or Zinsco panel, and any time you smell burning or feel heat. While you're at it, test your smoke and CO alarms.

Sources (2)

InterNACHI: Electrical Service Panels · ExpertCE: Identifying Zinsco and Federal Pacific Breakers

Related: Mold vs. Mildew: How to Tell and When to Worry