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Blocked AC FILTER ELEMENT

 

I use gravity fed activated sintered carbon filter element for potable water requirement. It gets blocked after some usage. Can some one enlighten me the causes leading to the blockage? Is there any method by which the filter can be reactivated?

N.G.KRISHNAN
- Bangalore, Karnataka, India

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Assuming that particulates in the feed water are not blocking the filter, the activated charcoal is probably removing the chlorination from the water. The charcoal then provides an ideal medium for the growth of bacteria. The only cure is to periodically sterilize the carbon bed. Steam or VERY hot water will work or you could try cold chemical sterilants such as sodium hypochlorite.

Good luck,

John Holroyd
- Elkhorn, Wisconsin

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Microscopic algal material is a common cause. If it is a huge vessel, scrape off the top 2 inches and throw it away. Remember, the reason you are using it is to remove something from the water. It does not have an infinite lifespan. A crude figure would be 5,000 gallons per cubic foot if you were trying to remove chlorine only.

If your water is dirty--relative term-- put a 5 micron particulate filter in front of the carbon. This will require a small pump.

James Watts
- Navarre, Florida

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Hi N.G.K.

What James Watt said about a 2nd filter makes a lot of sense.

You can buy (very cheaply) PP filters from l00 to, I think, 2 micron sizing. Mind you, the small sizing plugs up very easily.

Seeing that these PP filters (2" or so in diameter) can be so easily used (and removed), I'd go to a coarser 50 micron size and then to a 5 or so micron size. Using a pump with a pressure gauge set-up will soon tell you when to change/clean the filters.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).