[Greenbuilding] Water Filters

[Lawrence Lile]

What do people think about home water filters?

Here is what I think -

1.  They are overrated.  Unless you have a specific water quality problem, water (at least in the US) is generally pretty good and doesn't require a filter.

2. That being said, I have one, because my water tests positive for radon. It is very hard (15 grains per gallon), and is essentially untreated chlorinated well water, from a public rural supply in limestone country.  I'd rather not drink any radon, thank you. Rather not breathe any either.  The filter at the kitchen sink combines activated carbon and reverse osmosis, which gets rid of a lot of stuff.  I've radon tested the house and not found any radon problems in the house as a whole.

3. I also have a sediment filter at the inlet to the house, because when I first built the house the lines were full of a lot of sediment, and I was worried about clogging up new equipment.  I probably do not need this filter at all after a year of flushing out the lines.

So after a certain period you are supposed to change the filters out.  Most consumers skip this step, and slowly develop a sediment-filled bacteria farm in their supposedly clean filtration system.  My brother in law has an RO system from the 1980's that's never been changed, despite my warnings.

My water filter even has a little light, which goes off after exactly 6 months even if you've never turned on the tap.  Hmmm. The filter-change-indicator-idiot light doesn't connect with the reality of water use.

Hacking this system a little, I decided to see if I can extend the life of the expensive osmosis canister.  I reason that if the canister is working correctly, then the water coming out of it should not test at all for hardness.  So I'll change out the two less expensive carbon canisters on six months intervals, and only change the RO canister when my hardness test kit says the filter has quit working.  Hardness test kit is in the mail, and was cheaper than a new RO filter.

If Radon weren't present, I might have put in a carbon filter system, or none at all.  The RO system is expensive, but the only one that will get rid of such contaminants.

I've a mind to scrap the big particle filter on the inlet to the house, but I still worry about trashing expensive appliances that I just sunk a lot of money into, with silt.

My hot water system runs on soft water, whereas the cold does not.  This conserves water softener resources, prevents calcification of your water heater, reduces salt flow into the sewer, but doesn't result in that slick, can't-remove-the-soap super soft bathwater that 100% soft water produces.

Egad, what a complex water system.  What have other people used, how have things held up, do you ever change the filters?