Re: GE R.O. Water Filter

[Keith <keseymour@xxxxxxxxx>]

On Tuesday, December 16, 2014 11:55:02 AM UTC-5, Pat wrote:
> I installed 3 of the subject GE reverse osmosis water filters about a
> year ago.  (The model number is PXRQ15RBL).  My daughter wanted one
> (because she didn't like Los Angeles city water), so I stalled one at
> her place.  I liked the way it installed easily, so when I returned to
> my Ohio well water, I installed an identical model here.  Our well
> water wasn't bad.  There was an occassional slight sulfer odor, but
> testing indicated no harmful bacteria.  It is also softened.)  The
> filter seemed to work well, but I found myself also drinking water
> from a bar sink in the basement family room.  This seemed silly since
> I had installed the filter upstairs - so I bought another filter and
> installed it at the basement bar sink.  That's it for background - now
> to my question:
>=20
> The manual says to replace the "pre" and "post" filter canisters every
> 6 months.  To make the product seem high tech, they even provide a 6
> month timer that lights an LED when the 6 months is up.  That is all
> it is - a timer.  It does not measure usage, flow rate, or
> contaminates at all.  So, how often do I really need to change the
> canisters?  The filter installed upstairs is used for making coffee,
> tea, and meals every day, while the filter at the bar sink is used for
> only a few ounces of water no more often than once a week.
>=20
> I can't imagine why both units need to have their filters changed at
> the same time.  Do the filters get clogged?  (Mine haven't even on the
> higher use sink).  Do the filters become contaminated with bacteria?
> In that case, the lower use one might be worse.  (In my case, there
> have been no foul odors nor reduced flow).  Both LED indicators went
> on at 6 months and blinked until the batteries died.  I just can't see
> spending $80 every 6 months for no reason.  Does anyone have any
> inside information or real experience regarding these things?  How can
> I tell when they really need to be changed?  Am I being reasonably
> frugal or risking my life?
>=20
> Pat

Pat,

I worked in water purification for some time, the real way to test for a fi=
lter that needs changing is the pressure drop over the unit. That applies t=
o the RO unit as well as the prefilter. If you run the filter too long it w=
ill rupture and the pressure drop will decrease drastically and all of the =
impurities will flow into your water.=20

For the un-fun part the manufacturer would be the best person to tell you w=
hat that pressure drop is to change the filter before you have a problem. I=
n the home automation group I suspect the solution would be to track the pr=
essure drop and have a light green as long as it's increasing and red when =
it decreases.=20

For the most part you are safe because the contaminants are limited to the =
input side, any additional bacteria that grew would generally grow on the d=
irty side of the filter. This will increase the pressure drop but not incre=
ase your risk.