Simple filter to dechlorinate tap water

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Scriv

Well-Known Member
Joined
Dec 30, 2014
Messages
461
Reaction score
120
Location
Modesto
Does anyone have plans or a parts list to build a simple filter to dechlorinate tap water? I'm thinking something along the lines of a Pentek filter housing with a cartridge and some way to connect it to a faucet.

Any help would be appreciated, thanks!
 
Sure. No brainer.

We size carbon filters based upon the desired flow (in gallons per minute). The faster you want to push chlorinated water through the filter, the larger the filter needs to be. As no filter is 100% effective, you can also use two carbon filters rather than one, if desired.

If you want to extend the life of a carbon filter cartridge, it should be preceded be a sediment filter with a pore size smaller than the carbon block pore size.

Feel free to give us a call if you'd like and we can spec what you need.

Russ
513-312-2343
 
I'm using a dual cartridge filter like shown. Works great but flow rate is slow at around 2-3 litres per minute. You can run faster but still taste the chlorine.
As mentioned above, I run a sediment in the first cartridge. Thinking about going dual carbon to up the speed a bit.

image.jpeg
 
There are four standard sized carbon block cartridge filters, and the larger carbon blocks can handle higher flows:
10" long x 2.5" in diameter (typical max flow rate of ~1 gpm)
20" long x 2.5" in diameter (typical max flow rate of ~2 gpm)
10" long x 4.5" in diameter (typical max flow rate of ~3 gpm)
20" long x 4.5" in diameter (typical max flow rate of ~6 gpm)

In practice, we tell people to keep their flow to no more than about half the manufacturer's stated maximums.

Just for context, flow from a wide open kitchen faucet is typically around 2 to 4 gpm.

Remember we're talking about radial flow carbon blocks here, rather than axial flow GAC cartridges.

Russ
 
I'm using a dual cartridge filter like shown. Works great but flow rate is slow at around 2-3 litres per minute. You can run faster but still taste the chlorine.
As mentioned above, I run a sediment in the first cartridge. Thinking about going dual carbon to up the speed a bit.

Those housings look like they take the 20" x 4.5" cartridges. You could use a smaller (less expensive) housing and sediment filter ahead of those if you wanted to use two carbon blocks.
 
actually, I grabbed the pic online. Mine are standard 10" X 2.5" and your recommend about half the stated flow rate is right on. That might even be a bit much.
I measure correct flow rate by simply tasting the water. anything more than about 2l per minute is too fast.

I do have another single cart housing, I may just add that in so I can run 2 carbons
 
I use an RV filter. It just goes on the end of your hose. It's a carbon filter so it removes chlorine. Works at a fairly high flow rate, but I slow it down to give the carbon time to work. I also bought a brass valve from the hardware store to controll the flow at the end of the filter or shut it off. I also use a white potable water hose so I don't get that garden hose flavor in my beer. It was the cheapest and easiest set up I could come up with and I have had good results. Here is a link for what I'm referring to. http://www.walmart.com/ip/14504321?...39127952&wl4=&wl5=pla&wl6=78652300112&veh=sem
 
I use an RV filter. It just goes on the end of your hose. It's a carbon filter so it removes chlorine. Works at a fairly high flow rate, but I slow it down to give the carbon time to work. I also bought a brass valve from the hardware store to controll the flow at the end of the filter or shut it off. I also use a white potable water hose so I don't get that garden hose flavor in my beer. It was the cheapest and easiest set up I could come up with and I have had good results. Here is a link for what I'm referring to. http://www.walmart.com/ip/14504321?...39127952&wl4=&wl5=pla&wl6=78652300112&veh=sem
A carbon block would easily out perform a GAC filter - but if its working for you, that's all that counts!
 
Remember that the time that the water is in contact with the carbon media is critical in this application. Chlorine removal is fairly simple to accomplish with the flow rates that Russ presents in Post #4. However, the residence time has to increase markedly to effectively remove chloramines and some other taste and odor compounds. In general, you would have to reduce the flow rates to one-tenth of the rates in Post #4 for chloramines removal. Yeah, that sucks.

One thing that you should consider to help your new filter system to stay at a properly low flow rate is to insert a restrictor in the flow path. In the case of the 10" x 2.5" filter, inserting a plug with a 1/16" hole in it will reduce the flow rate to about 1 gpm under typical water pressures.

Carbon block is essentially granular activated carbon that has been compressed and solidified into a more dense, but still porous media. In essence, you are getting more carbon with the block than you get with GAC since the GAC has a lot of voids in the media. Go with carbon block anytime there is a choice.
 
A carbon block would easily out perform a GAC filter - but if its working for you, that's all that counts!
The water in my area fairly good for most styles without huge flaws. I've talked to most of the local brewery's making good beer in the area. Two of the better brewery's don't even filter. The chlorine comes out in the boil they say and only add minimal calcium for certain styles. I also know a few excelent home brewers that only rely on the boil to rid them of chlorine. I only use the filter out of my own paranoia. But I know for a fact my city uses chlorine and not chloamine. If they switch it will be better filters and campden for everyone!
 
I wouldn't need more than 1gpm flow rate, I'm only going to be using this for 10 gallons of brew water at a time. I currently buy bottled water at $1 a gallon, so I want a solution that is reasonably priced. The rv filter looks ok so far, or a Pentek 10" housing with a carbon block filter.
 
I wouldn't need more than 1gpm flow rate, I'm only going to be using this for 10 gallons of brew water at a time. I currently buy bottled water at $1 a gallon, so I want a solution that is reasonably priced. The rv filter looks ok so far, or a Pentek 10" housing with a carbon block filter.

The RV filter can also be stored in the fridge and reused. I go 6 months but I've read a few people using them up to a year. They're good for way more gallons than you'll use brewing once a month. What you need to worry about is mold. I just cap mine and store it in my keezer. I then let water run for a minute or so the next time before I use it. There are a lot of right ways. This is just my way!
 

Latest posts

Back
Top