OT - back flushing refrigerator water filters

We had a GE refrigerator for years, that used the MWF style filter. That filter lasted for 4 to 6 months typically, unless there was road work or a pipe break (municipal water supply) that caused a slug of sediment to come through the pipes. In that case, it would plug quickly and need to be replaced.

After 20 years of that refrigerator (it was flawless, but being a counter depth it had limited room), we replaced it with a Samsung. This new Samsung uses DA29-00020B water filter. These have lasted about a month each. When new, they will put out over 32 ounces before the auto timer kicks out. I can track how bad they get when I fill a measuring cup to fill the tea kettle (that doesn't fit directly in the water dispenser cutout).

After going through several, and these filters aren't cheap, I finally went and installed a whole house 15 micron filter (large GE cartridge). And now here I am a few weeks later, the whole house filter is still mostly clean (water pressure in the house is fine), and I need to replace the refrigerator filter again. I do not want to just gut a filter and use it as a plug to get water through, but not filtered. The filters I have been using are real Samsung, not counterfeit. Really don't want to install another 'polishing' cartridge filter for just the refrigerator, but could if needed. Just not an easy place to do it.

Questions -

Years ago when I would camp, there were portable filters that could easily be backflushed, so I figure I could do the same. Any standard as to which is inlet and outlet on the filter? I am guessing inlet is center, and outlet outer ring. It would be easier if the normal inlet was the outer ring, so I could simply backflush through the center. Anyone know?

Is there a standard fitting of some sort for the filter mount, that I can buy and easily make a backflush device? I don't want to buy a replacement part from Samsung, but guess I could. The local dump frowns on pirating parts, especially from freon containing appliances.

There must be a market for an inexpensive backflush device. I can't be the only one with these problems. So if anyone wants, here is a business idea.

Thanks.

Inner diameter about 14mm, outer about 27mm, by a quick eyeball with a ruler.

Could you determine which one is the inlet from where it connects to? I'm thinking have an assistant just barely crack the water valve briefly while you watch (perhaps with a mirror and towel to avoid getting sprayed).

mfisher said:

There must be a market for an inexpensive backflush device. I can't be the only one with these problems. So if anyone wants, here is a business idea.

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BTDTGTTS, US (hardly a problem, Loudoun Water) , also Hong Kong, plus mainland China (MAJOR issues).

Fool's errand, the backflush.

Your 'whole house' filter is the start of a better solution.

Mine evolved over 25+ years, into an array.

Hong Kong it takes up under-sink space, filters are close to the door, no longer in the back of the cabinet where we started. Position makes for easier access for frequent changes.

Zhongshan holiday home, filters were mounted outdoors for easy access. It doesn't freeze there.

Virginia, they are mounted in the lower-level of a 3-level split above a laundry tub. Again, easy access for frequent changes. Tub catches any spills when changing, a source of water is 'there' for cleaning the housings.

The 'array' starts with large 'yarn' type cartridges that stop mud and rust scale from getting to the more costly - and delicate - activated charcoal filter and the resin filter.

A separate 'bus' (copper tubing) distributes the filtered water to 'many' points of use.

There is probably 20 feet of copper tubing and a dozen fittings in the Virginia installation, half that and of smaller diameter in Hong Kong.

PITA? Only the one time when it was installed. Costly? No, not really.

In the years since, we get to use larger, but cheaper 'generic' OR brand-name cartridges, change them less often, always have better water at all points, fridge-freezer, hot-water soup/coffee tap, drinking water & cooking taps.

On-fridge filters - fed nothing but already triple-filtered water, day of install onward, last longer than the fridge itself.

If you are renting or planning to move soon? Don't bother.

If it is your own home and even for five more years? This sort of effort will pay for itself just on the ability to use the big filters that are so much more common, offer more choices of type of filtering, and are more competitively priced.

BTW . this rig specifically does NOT cover the 'whole house'. No point in wasting filtration costs for laundry, showers, washing the car or patio.

If your water is bad enough to need that, even for washing a dog?

Use a separate filter. Larger one, preferably two, side-by-side with valves to be able to change one at a time.

Bill

Backflushing is as simple as replumbing inlet to outlet with a series of ballvalves and a drain.

Instead of wasting your time with backflushing (it won't work anyway for a lot of reasons) I would spend my money and time installing two more large inline filters at 5um and 1um that only feed your cold water lines to the fridge and kitchen tap.

I would ditch the fridge filter altogether and enjoy clean water from your fridge and tap sources, add a 0.1um filter plus housing and UV lamp and your have sterile water which is as good as it gets...expensive filter changes though. Most people use reverse osmosis systems to get this level of clean since its cheaper but a lot goes down the drain to get it.

4JawChuck said:

Backflushing is as simple as replumbing inlet to outlet with a series of ballvalves and a drain.

Instead of wasting your time with backflushing (it won't work anyway for a lot of reasons) I would spend my money and time installing two more large inline filters at 5um and 1um that only feed your cold water lines to the fridge and kitchen tap.

I would ditch the fridge filter altogether and enjoy clean water from your fridge and tap sources, add a 0.1um filter plus housing and UV lamp and your have sterile water which is as good as it gets...expensive filter changes though. Most people use reverse osmosis systems to get this level of clean since its cheaper but a lot goes down the drain to get it.

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I hadn't considered UV lamp, nor Silver catalyst (splits O2 to nascent O) here.

So long as.... the 'service' is plumbed only to directly enhance drinking, ice-making, and cooking water outlets AND NOT the wash sink(s) nor dishwasher (it has a sterilizing heater..) , and certainly not laundry, terlets, showers, hand-wash basins, outdoor hose bibbs?

IOW specifically NOT "whole" house .. .. the filter changes are infrequent and only the resin one particularly costly.

Saves a lot of store-bought water being hauled in, plus the associated hassle of recycling its plastic. Generally better water as well than most of those packaged rip-offs.

Bill

Cut one open and work out whats plugging it, also try a finer filter in the whole house one. Chances are good the incoming supply is fine, but the plumbing on way to the fridge has something breaking down. Back flushing carbon block filters does not work. Work out what your real issue is and fix it.

Generally 15 micron is too coarse before a carbon filter block. Most people use something a lot finer and normally have multiple stages, if the whole house 15 micron catches nothing its achiving nothing, fit a finer element there for starters.

Filter micron rating needs either expensive testing or some simple trial and error. Basically if they plug too fast you want coarser and if they show minimal sediment you want finer, goal is that all filters clog at about the same rate, ideally over a say circa 4-6 month period. Sometimes depending on supply particule fiters will plug first and have to be changed more oftern, but above all you don't want the carbon block which is what removes your chemical nasties plugging up at all, you want it free of particulate to treat the water chemically not as a cow catcher which will rapidly degrade its performance.

Filter cartridges as small as thoes inline ones won't ever work in a demanding application, far better to go for a proper bank of 10" filter cartridges and do it properly.

I agree that you should 'protect' the Samsung filter with pre-filtration. If the Samsung filter never sees any junk it should never need changing.*

That said, you must have a lot of crap in your water to use up a filter in a month.

More to the point, it's a huge racket for the refrigerator makers selling filters for $40 that cost $2 to make. We all know those bastards could easily design a larger filter that costs less.

*I'm curious just how the fridge 'knows' the filter is in need of changing. On most of the fridges I've seen, a little light comes on when the filter is 'clogged'. The engineer in us all would tell you that they have a sensor which can measure pressure drop across the filter and it knows when it is too clogged to flow well. The realist in us all suspects they have a simple timer programmed into the jackass computer chip which trips the light every time the Samsung stock takes a dip and they need a little extra cash so they can have more Gangnam Style.

If yours is like mine you can just take off the filter and the base bypasses on its own and install a external filter on the water feed line

Mine took about nine months from new before the change filter command came on. I am going to take the filter out and look at it before replacing. If I do not see anything, I may put it back in. If the signal comes from pressure drop, it should let me know quickly. If from time, maybe it will reset. My house has a water treatment system, so the water should be relatively clean.

Jim

Jim Williams said:

Mine took about nine months from new before the change filter command came on. I am going to take the filter out and look at it before replacing. If I do not see anything, I may put it back in. If the signal comes from pressure drop, it should let me know quickly. If from time, maybe it will reset. My house has a water treatment system, so the water should be relatively clean.

Jim

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That was one of the things I wondered, whether the filter actually needed changing or if the warning was a timed event.

I assume there must be a way to reset it when the filter is changed and with enough pre-filters it should last a long time.

A good rule of thumb for whole house filtration is 20-10-5-1 (in microns i.e.um) with take offs in between for various service levels, you could even add a 40 prefilter if you had a lot of sediment.

Much of this depends on a water quality test which you should do before investing in a filtering scheme, not an expensive test to do. What you ask for is a TDS test and bacterial load assay, this will tell you if you need a 1.0um filter or not, ideally you don't want to have to run this small a filter if you don't have too...they are the most expensive.

If you have a water softener you want to filter sediment prior to hitting resin and then fine filter after it, as you can see everything depends on your setup and water quality.

I used to set up/repair pure water systems for medical/research applications, ask any questions you may have here.

Thanks for the inputs. Some responses:

There is no shutoff valve on the fridge to close before changing filters. You can change 'on the fly' without any water leaking. Plus the filter slides into a tube like cavity between drawers. No way to see there which is in or out.

It is not really a whole house. Locations to install were very limited, but basically it does just the kitchen.

Not possible to arrange valves to backflush, it is built into the refrigerator.

Pipes are all good. All copper installed 12 years ago. When I cut in for the 'whole house' filter, the insides were basically clean.

I know when it is time to change because the flow rate drops dramatically. When new, I can run 32 oz without the timer shutting it off. Right now I get 12 oz when the timer shuts down. There is a timer on the refrigerator that is set to 6 months.

The GE refrigerator / filter did not have such extreme problems unless the city was doing work like flushing the fire hydrants or doing roadwork - things that will stir up the sediment for a day or two. GE filters lasted 4 to 6 months.

The water itself is rather good, compared to many areas (I travel quite a bit for work and get to experience a wide range, at least as far as taste goes). We get annual water reports from the county that summarize the monthly quality from each of their plants.

No water softener. Not needed.

Sounds like the 15um filter is just too coarse to protect the refrigerator filter. Looks like my next step (unless I get into an RO system, which is not out of the question, but seems a bit overkill for what I really need), is to find a spot to put a 5 or 1um filter in, just for the refrigerator line.

Honestly I would find a way to defeat the internal filter on the fridge, they are way over priced for their capacity.

You should be able to find the micron sizing from the mfg of the filter, should be on the packaging or on the filter somewhere.

Once you find out what it is just remove the filter and use a standard cartridge inline, my guess is its a 3 micron. I would suggest you multistage (even if its only two filters) with the final filter being an activated charcoal carbon block style at 0.5 micron, the improvement in taste especially for things like coffee is worth it IMHO.

Doing a TDS assay will tell you how big the load is and what micron size, just ask the water testing lab what your doing and they will guide you to their standardized test and likely even suggest suppliers in your area that are cost effective. I think you will find these people to be the obvious experts of water quality for your area for good reason, honestly the best $75 you will ever spend.