I just want to caution everyone who wants to buy a 3M Water filter system from Costco to buy extra filters. When you buy certain products from big box stores, they have the right to customize the product to their own specifications. This was the case of Costco.
Since the filters were costly, I just bought one replacement filter every year. Then this year when I went to buy the replacement filter I noticed that it was not the same size or shape as last time. They had redesigned the filter system and the old cartridges were no longer compatible. My wife made serveral phone calls and was told a few different things like: B&Q has all our products. Go there and they will help you. … That turned out to be false.
Finally … we got the correct answer. Your installer will come to your house and retrofit your filter device to accept one of their new cartridges at no cost. He will also sell me the replacement cartridge which cost $1,600. Next year, we are to call them again to get a new filter. It’s working well. If you want the specific numbers or other info… post here or Private Message me.
If you are considering not buying a Costco filter, I’d buy it anyway. The installer told me that under the hood the filters are all exactly the same and to their job. It’s just the dimensions and the way it connects to the system that are different. Just buy a ahead. You can save a bit of money by going with Costco.