Is it necessary to replace a Federal Pacific panel?

[John Mayer]

And if so how much does that run in Denver?

[Steve K.]

Here's the deal with Federal Pacific Electric panels: They start fires. Some people will tell you "It's been working fine this long, why would it cause a fire now?" That's terrible logic. Electrical equipment does not get better with age like women and wine, in fact it becomes more dangerous from years of expansion/contracting (electrical fatigue) as well as handling larger loads than it was designed for, making it more likely to fail and cause a fire as time goes on. The fact that FPE panels are all over 40 years old at this point (because the company went out of business around 1980 instead of facing multiple lawsuits due to people dying from house fires) alone is a reason to replace them. Age aside, FPE panels were never any good to begin with and should not have been allowed in dwellings. FPE "Stab-Lok" breakers (red strip across the front, often says Stab-Lok somewhere on the panel) fail to do what they were intended to do, which is trip when shorted or overloaded. Instead of tripping they get extremely hot, melt/arc and start fires. When I was selling residential solar I assessed 3-6 homes a day and often saw FPE panels with charring around where a breaker had been overheating for awhile and started arcing because it failed to trip, causing the breaker to melt and the wood framing the panel was mounted on to start burning. There have been thousands of house fires and many deaths caused by FPE panels over the pat few decades. 

I don't trust any FPE panels as besides the breakers being defective the busbars themselves have also been known to cause fires because they used a screw that was undersized to attach the busbar. I've seen breakers just fall out when opening the cover. These things are bad news, I would not have one in any property I own for any amount of time. 

 I'd demand the seller replace it as it's a well known and documented safety issue; textbook inspection objection item. Replacing the whole panel is the only way to address the issue. However, in your case since it sounds like you have a really good deal on your hands, so you might consider just eating it and moving forward on the purchase if the seller refuses to replace it. Looking at the big picture, $2,000 may not be a deal breaker (pardon the pun). $10/Amp is the going rate in Denver for a panel swap and you'll probably want to upgrade to a 200A panel=$2k, and hit me up if you need a good electrician. 

Just whatever you do, please have it replaced before you move in. Also as a heads up, in the meantime before you get it replaced, if you're working on any outlets or anything and you want to shut power down, just be aware that tripping the breakers may not actually de-energize the circuits!

Other bad panels to watch out for are Zinsco's (not all of them but some Zinsco breakers are the same Stab-Lok design and melt to the busbar), Zinsco's rebranded as GTE-Sylvania (but not all GTE-Sylvania's), and some panels made by Challenger Electric, Westinghouse, Bryant that used a similar design as the Stab-lok/FPE for awhile but these are far less common and not all panels made by those brands are bad like FPE, although they are all also really old which is sketchy), split bus panels, fuse boxes, knob and tube wiring, aluminum wiring, undersized 60-100A mains, etc.). Good stuff to look for during inspection. 

 Good luck with the inspection negotiations! Did you also check for Aluminum wiring and ungrounded circuits? Those are additional issues that some people like to say are okay, but really aren't. Those issues are a little more complicated than FPE, not as critical but still definitely a concern. FPE is simple: replace immediately before it burns the place down. 

(some of this post was cut and pasted from another post I made a few months ago on FPE panels)