After far too many repairs, we bought a new Brita pitcher with slightly different, although apparently equally crappy, hinge pins, whereupon I bandsawed the long-failed “smart” filter timer out of the old pitcher’s lid:
The gray rectangle is the LCD panel showing how long since you last replaced the filter. It died some years ago and, indeed, the CR1616 battery was down to 2.8 V.
However, I think the real failure happened when the black square of conductive foam slipped off the switch contacts under the Reset pushbutton’s stud and went walkabout inside the timer:
That’s where I found it after sawing the casing open. I think the adhesive side should be stuck to the stud, but we’ll never know.
The new pitcher includes a different indicator with green LED status blinkies for “Standard” (40 gallon) and “Longlast” (120 gallon) filter cartridges and a red blinkie for “Expired”:
Yeah, purple. For some unknown reason, it cost 10% less than the other colors and we’re not fussy.
This one measures filter use by water volume, not elapsed time, counting the number of pitcher refills by noticing when you open the flip-top lid; the corresponding volume depends on your ability to see a nearly invisible line molded into the lid. Unsurprisingly, Longlast filters cost only slightly less than three times standard ones, so they’re not a compelling value proposition.
The Smell of Molten Projects in the Morning 
The last batch of Brita filters ended up too loose in our pitcher, and the set got demoted to shop refrigerator duty. We now have a Pur pitcher and are on our third filter. Same 3-LED setup as our Brita has, but their filters actually lock in place. The Britas were floating during a fill unless we forced them down. Unfortunately, no Costco deals on Pur filters, but Amazon has 4 packs. (FWIW, both of our pitchers use a position sensor to detect a pour. Neither cares about refilling.)
Although new filters should fit old pitchers, the comments I saw suggested something wasn’t quite right, so I sprang for the new pitcher. It’s not like the old pitcher was in perfect condition.
Surely the difference between counting refills and counting pours comes down to a patent shootout. In any event, your water surely puts the hurt on filters: you know when they need changing!
Questions…
1) Why do you use a water filter?
2) How can you tell it is effective?
3) How does this electronic device “know” when it is necessary to change the filter?
4) Would an obstructed filter require noticeably longer time for unfiltered water to pass through into the pitcher?
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1) Our well water has interesting minerals in it; very volcanic area, so iron, sulfur and calcium along with carbonates. I’ve been in areas where the water content of the chlorine solution isn’t high enough…
2) Taste, usually. We don’t have particulates, though when I used a water still, the residue was funky.
3) Dunno on Ed’s, but I think ours is a SWAG, either based on an average quantity per pour, or it actually times the pour. The older mechanical timers counted the number of refills.
4) Haven’t noticed any delays. The PUR filters can clump up; there’s a note telling how to get the activated carbon to declump (basically a mild thwacking).
With the new well, the water quality seems to be much better than the original. I wasn’t thrilled at the segment of old pipe when that had to be cut; the old well should have been disinfected some time ago. (Although, that might have raised hell on the ancient galvanized piping in one of the houses on that well. Milage may vary.) We are used to the water (Julie tends to use filtered water for baking, while coffee and tea water is strictly from the tap), but we’ve kept bottled water for guests.
The Po-city water plant switches between chlorine and chloramine (chlorine + ammonia) every now & again, for reasons we don’t understand, and I think they’re using the latter now. We dislike the smell and the filter tamps it down just fine: we know the filter works and when to replace it just by smelling the output!
The usage meter in the flip-top lid counts each time you refill the reservoir, which has a fill-to-here line. They know the filter’s capacity under worst-case conditions, divide that by the volume per fill, and presto that’s how many refills get the green blinky LED signal.
I put a big sediment filter on the water inlet, back when we were using well water, and it knocks down incoming crud. Mostly, there’s no problem, but when they flush the lines in the spring the filter turns dark in short order.