Under sink water filtration system

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.

#1: Post by TMNTony »

I just purchased an new home that has a wet bar area with a small sink. I am thinking that I would like to put a filtration system under the sink so I can fill up my reservoir from the tap as opposed to plumbing my machine in. So that leaves me with a couple of questions:

1. What would a good filtration system be to avoid scale?
2. What kind of life can I expect out of these cartridges if I'm also using the sink to rinse pitchers and cups?
3. Is there another solution I should be looking for?

Thanks for your input

Team HB

#2: Post by Jeff »

Knowing your water supply will be needed to make meaningful recommendations. It might need "nothing" past sediment and chlorine or chloramine, it might need a lot. Do you have your supplier's water quality report?


#3: Post by TMNTony »

https://www.bwwb.org/sites/default/file ... 0_AWQR.pdf

I always have a hard time interpreting these reports, so I would appreciate the help


#4: Post by karamba »

Looks like you are the lucky one and have ideal water in your municipality. I would skip filters and just enjoy coffee.

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Team HB

#5: Post by homeburrero »

TMNTony wrote:https://www.bwwb.org/sites/default/file ... 0_AWQR.pdf
I always have a hard time interpreting these reports, so I would appreciate the help
One problem with that water is the high variability of the reported hardness. The general hardness as reported is between 48 and 126 (they don't say the units, but surely must be mg/L CaCO3 equivalent.) Then they give a range of 12.6 - 56.1 for calcium, which would be a top end calcium hardness of 140 mg/L CaCO3 equivalent. (The discrepancy here is probably due to different samples for the different max measures).

Those differences may be regional, with some neighborhoods at the high end and some at the low end, or may be seasonal or unpredictable as the water utility shifts between their different sources. You might be able to nail it down better for your neighborhood by calling the utility.

Given the alkalinity of 20 - 86 mg/L along with calcium hardness of 31 - 140 mg/L you are looking at water that may or may not be scale prone. If you're willing to watch for scale and occasionally descale as necessary, then you can try going with a simple an activated charcoal or carbon block filter to handle the chlorine, taste, and odor.

If you're in the camp that prefers to use water that requires you to descale rarely or never, I'd say use a conventional softener along with charcoal. You can use a generic setup like they sell at Chris Coffee, or opt for a single cartridge like the 3M-Cuno ESP series that contain both a conventional softener and a charcoal/carbon filter. With conventional softening* you will keep that 20 - 86 mg/L alkalinity, which is recommended for machine health and is not too high for optimal espresso taste.

The really good news in that report is that your water is reasonably low in chloride ion content, so you aren't forced into using a reverse osmosis system to remove corrosive chloride. (Note, chloride is not the same thing as chlorine.)

* By conventional softening I'm referring to an ion exchange resin that exchanges sodium or potassium for the calcium and magnesium ions. The alternative is a decarbonizing or WAC ion exchange resin that exchanges H+ ions for the calcium and magnesium. BWT bestmax, Claris Ultra, Mavea Quell are examples of the latter, which reduce alkalinity and tend to acidify the water. With only 20 - 86 mg/L of alkalinity a decarbonizing filter is not the best choice IMHO.
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