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Question: I bought the Zero Water  filetration system that has 23 cup capacity.  I don't know what my filter number is?  Which replacement filter do I buy?
Document: I bought this after reading the reviews. My plan was to try it out, then return it. Because I really didn't expect it to be so good. The water taste so good! I thought I was going to have to spend a fortune on filters, but again, I was pleasantly surprised. I've had it for a month and the water is still reading zero! Buy this and you won't regret it!! !ZeroWater ZD-023 23-Cup Water Dispenser and Filtration System
We liked this water filter until after 9-months the spout broke. No replacement parts available. As I look through reviews, I see this is a common problem so I won't buy another unit. Extra filters will go unused. What a waste of money on this water filter system.UPDATE: Contacted ZeroWater direct and told them of our problem. Within 24-hours they sent a new 23-cup dispenser with a note to keep all other parts, just the tank and spout will be coming.
After only 5 weeks of owning my Zero Water 23 cup water dispenser, the spigot broke. I tried to return it through Amazon but my return date had already passed. So I called the 800 number for Zero Water and left a voicemail for them. They called me back the same day and sent the entire blue portion of the system to me for FREE!
This is the best water filtering system in my opinion. It is well worth the wait for the water to filter. The 23-cup capacity allows you to keep it full. When it is a little under 1/2 full, I simply top off the top reservoir for it to filter. This includes the filter and a water tester.
I've only had this water filter system for a month now and I love it. I've given away our nearly new Brita as this works so much better. I love the 23 cup capacity and would give it a 5 star rating if it wasn't for the fact that it's difficult to get the water level to go much higher than halfway up the dispenser which means constantly filling reservoir to get the level up high enough to last in our family of heavy water drinkers.
I do like how well they work and think the cost is justified. When I used the tester on the tap and Brita filtered water I was shocked how little the Brita filter was taking out. There is a taste difference with this water filtration system but now it just tastes like bottled water instead of filtered.Update:  We have now had this system for over a year. Although the water is tastes great and the larger capacity is great for a family. I don't know I would buy this system again.
I bought the large 23 cup model and after 2 1/2 weeks the water tastes like sour lemons. I live alone so I know it was not from using too much water on 1 filter. The filters cost around 15$ so  30$ a month for water?? Too much for me.Most other reviews are the same. Check before you waste your money. BAD,BAD,BAD
I had to return the first one I bought becaus the spiggot leak. I tleaked bad enough that when it started leaking it leaked out the whole contents on my counter top. Amazon replaced it and now the replacement containers spiggot is leaking. Neither one of the containers would ever let near the capacity filter through into the dispenser part of the system. I really hate to rate badly because the water turned out great but I read several other reviews and they had spiggots leak too.
We usually go to a local water station to get our filtered water, 12 gallons at a time. We were getting a little tired of doing this, so we tried the ZeroWater 23-cup system. It seemed to work really well, the water tasted good, and the TDS meter showed 0 ppm. Our Tucson tap water is about 330 ppm total dissolved solids, so we weren't sure how long the filter would remain under 6 ppm (their recommended replacement value).
My new ZeroWater 23-cup dispenser makes the best-tasting water I have had with a home filtration system. In fact, Brita has some 'splaining to do, Lucy! I tested the water with the ZeroWater tester and found that the water from my current Brita dispenser measured the same as my tap water! I wondered why it still tasted bad after filtering with the Brita, and now I know!
Answer: ZR-017 is the filter number for this water filtration system. I just purchased both the system and replacement filters this summer.