Do you have a recommendation for a whole house surge protector? Would be interested. . . .
From
(This is a rough idea of risk, though not exact; we are in a 0-0.75 hits/year zone and we average more like 3-8 nearby hits per year, and our power line crosses several local high points.)
I would look for a vendor with a reasonable warranty and guarantee; the MOVs used in surge suppressors come in all sorts of quality levels, and I think that this is not a point to necessarily pick the least expensive.
Of the whole house protectors (these aren't lightning arrestors, which are a different product), there are external versions that need a breaker and are wired in, (these would fit any panel with the right breaker) and there are versions that look like a large double breaker. The latter are panel specific by vendor, so you may or may not have the option to use them. Some of the external versions aren't weather resistant. So, if you have an outside main panel and can't get to the backside readily, you will need to find a weatherproof unit.
Once you have a guarantee that you like, I think that the key feature to focus on is how much energy can they absorb. 40-50kA is the typical floor, and ones with over 140kA are available. Some versions (e.g. Siemen's BoltShield series) can be doubled or tripled up for additional protection. All of them are likely to be toast if you get a nearby hit. My view is that it worth the extra cost to go for a larger unit. For me, tripling the surge capacity didn't even double the price. If you are having an electrician install it, the cost is likely to be less than the labor for many parts of the country. Some guarantees require a licensed professional electrician do installation, so check the fine print.
All the big manufacturers make them; Eaton, GE, Intermatic, Square D, Siemens, etc. Due to panel constraints and supply chain issues, I didn't use a snap-in arrestor, but I did consider them. I think the upsides are ease of installation, and the proximity to the bus bars (distance). The downside is usually smaller capacity(kA), but some (most?) can be double or tripled up. I ended up going with a Siemens FS140, (
overview here). (I found it on sale for $224.) It was too large to fit inside my panel, so it was installed outside. The goal for the installation is to make the distance from the point of power entry to the arrestor as short as possible, which is why putting the arrestor in the panel has benefits, and why the arrestors (or the breakers for them) should always go in the first available slots.
I would view these items as consumables and expect to replace them every five to ten years depending on warrant/guarantee terms, and use. The core of almost all of them are MOVs, metal oxide
varistors, which have nonlinear resistance to voltage, and start to ground higher voltages to ground at just above normal line voltage. They can do this for small surges indefinitely, but at some level cross into a level that begins to erode the device, reducing protection. Most modern surge protectors have alarm circuits to let you know that they have failed.
I hope that this helps.
YMMV...
All the best,
BG