"Water Filters". Water filters cover the gambit from simple faucet filters, refrigerator filters, in-line filters to filter housings with a replaceable filter cartridge to all types of whole house backwashing / regenerating filtration systems that remove, iron, odors, manganese, radium, lead, turbidity and a plethora of other water problems. This subject covers such a wide range of water problems it could take many blog articles to cover just the basics of water filtration. One thing I know for certain though is what the typical consumer considers a water filter and what a water treatment professional would consider a water filter is totally different.
In the first "Water Filters" article we will look at filter housings and filtration cartridge options. Water filters installed for the whole house are called, Point of Entry (POE). Water filters used for specific locations, like under a kitchen sink, are called, Point of Use (POU). The most basic filtration is a filter housing with a replaceable filter cartridge.
Filter housings come in almost any size for many different uses. A standard filter housing for residential whole-house use would be 3" x 10" (lower left in the picture) up to 4" x 20" (upper right in the picture, here).
The problem is these replaceable filter cartridges are sold everywhere for rust, sediment, odor, and chlorine removal for water. Although they will definitely help reduce those things, depending on what filter is used, cartridge filters are not always the best options to do so and can plug up quickly causing replacement of filters frequently. This can become an expensive proposition as filter cartridges vary from a few dollars to over a hundred dollars. They can also significantly reduce water pressure and water volume. These style filters were very popular when well casings were steel. With steel well casings, scale, sediment, and rust commonly come off the inside of the well casing causing service issues with water treatment equipment. Cartridge filters, before a water softener, were a necessity to remove any sediment from this type of well. Today most drilled wells use PVC casings so scale and sediment issues have generally been resolved to the point where filter cartridge housings typically are no longer necessary. A good example where such filters are still an economical choice with good results would be the water issues in Flint, MI. Using a simple filter housing, with a block carbon filter, under the sink and tied into the kitchen cold water will greatly reduce the lead content, chlorine, and turbidity issues for drinking water. However, the filters would need to be replaced frequently, depending on how much water is used and the incoming water quality.
Replaceable filter cartridges are rated by "micron size" and/or specific contaminant removal. Filter cartridges come in micron ratings from .35 mic, to .5 mic. 1 mic absolute on up to 50 microns.
Examples:
1. A 10-50 micron sediment filter may be used before a water softener.
2. An activated carbon filter may be used for chlorine reduction.
3. A dual gradient filter such as a DGD 2501 removes larger particles on the outside (25 microns) and
increasingly smaller particles as it passes toward the center of the filter (1 micron) and is generally used as pre-filtration for laboratory use, machinery, and reverse osmosis systems.
The specific filter you may need depends on the water problem that needs addressing. If it's for sediment removal, before a water softener, I would recommend a 20-50 micron sediment filter preferably in a 4"x 10" or 20" BB housing. Cord wound, Poly spun, or Pleated filter cartridges are recommended for sediment removal.
There are many types of carbon and carbon filters for different water problems. As discussed earlier block carbon filters are frequently utilized to reduce lead content in drinking water. Another concern with municipal water supplies is "Chloramines" which are a combination of chlorine and ammonia additives added to municipal water supplies for disinfection. There are specifically formulated carbons to remove chloramine from your drinking water. Before using any filter for specific drinking water issues check the NSF guidelines for filter certification based on particular contaminant removal.
Filter Changing Tips:
1. Always change filter cartridges at regular intervals. Change the whole house filters every three months or sooner depending on the water quality and the amount of water used.
2. If you find you have difficulty removing the filter housing initially. Make sure the incoming water is off. Open a nearby faucet to relieve the water pressure, hold the pressure relief valve down, close the outlet valve when the housing is loose, and remove the filter housing.
5. Clean and sanitize filter housings whenever changing filters. Simply wipe out the filter housing, add a small amount of household bleach (tablespoon), rinse the housing out, and install a new filter cartridge.
6. When tightening the filter housing "never use a filter wrench". Hand-tighten the housing only to seat the o-ring. Using the wrench will flatten the O-ring causing it to leak and make even harder to get the housing off next time.
7. When replacing the filter leave the water valve on the outlet side of the filter off. Turn the water on slowly to the filter housing while holding down the pressure relief valve to release the air from the filter housing until all air is released then open the incoming water valve all the way. If there is no pressure relief button open a laundry tub faucet while turning the water back on to the filter to bleed the air off.
*Warning: Never use a cartridge filter for drinking water on a non-potable water supply.
In our next blog regarding "Water Filters", we will discuss whole-house filtration systems using backwashing filters and automatic regenerating filter systems to remove everything from sediment to iron, odor, arsenic, radium, and more.
I wish you, Good Days and Good Water!
Ray McConnell,
The Water Softener Blog
In the first "Water Filters" article we will look at filter housings and filtration cartridge options. Water filters installed for the whole house are called, Point of Entry (POE). Water filters used for specific locations, like under a kitchen sink, are called, Point of Use (POU). The most basic filtration is a filter housing with a replaceable filter cartridge.
The problem is these replaceable filter cartridges are sold everywhere for rust, sediment, odor, and chlorine removal for water. Although they will definitely help reduce those things, depending on what filter is used, cartridge filters are not always the best options to do so and can plug up quickly causing replacement of filters frequently. This can become an expensive proposition as filter cartridges vary from a few dollars to over a hundred dollars. They can also significantly reduce water pressure and water volume. These style filters were very popular when well casings were steel. With steel well casings, scale, sediment, and rust commonly come off the inside of the well casing causing service issues with water treatment equipment. Cartridge filters, before a water softener, were a necessity to remove any sediment from this type of well. Today most drilled wells use PVC casings so scale and sediment issues have generally been resolved to the point where filter cartridge housings typically are no longer necessary. A good example where such filters are still an economical choice with good results would be the water issues in Flint, MI. Using a simple filter housing, with a block carbon filter, under the sink and tied into the kitchen cold water will greatly reduce the lead content, chlorine, and turbidity issues for drinking water. However, the filters would need to be replaced frequently, depending on how much water is used and the incoming water quality.
Replaceable filter cartridges are rated by "micron size" and/or specific contaminant removal. Filter cartridges come in micron ratings from .35 mic, to .5 mic. 1 mic absolute on up to 50 microns.
 |
| Cord wound, Pleated, and Polyspun Filter cartridges |
1. A 10-50 micron sediment filter may be used before a water softener.
2. An activated carbon filter may be used for chlorine reduction.
3. A dual gradient filter such as a DGD 2501 removes larger particles on the outside (25 microns) and
increasingly smaller particles as it passes toward the center of the filter (1 micron) and is generally used as pre-filtration for laboratory use, machinery, and reverse osmosis systems.
The specific filter you may need depends on the water problem that needs addressing. If it's for sediment removal, before a water softener, I would recommend a 20-50 micron sediment filter preferably in a 4"x 10" or 20" BB housing. Cord wound, Poly spun, or Pleated filter cartridges are recommended for sediment removal.
There are many types of carbon and carbon filters for different water problems. As discussed earlier block carbon filters are frequently utilized to reduce lead content in drinking water. Another concern with municipal water supplies is "Chloramines" which are a combination of chlorine and ammonia additives added to municipal water supplies for disinfection. There are specifically formulated carbons to remove chloramine from your drinking water. Before using any filter for specific drinking water issues check the NSF guidelines for filter certification based on particular contaminant removal.
 |
| Block carbon filters |
Filter Changing Tips:
1. Always change filter cartridges at regular intervals. Change the whole house filters every three months or sooner depending on the water quality and the amount of water used.
2. If you find you have difficulty removing the filter housing initially. Make sure the incoming water is off. Open a nearby faucet to relieve the water pressure, hold the pressure relief valve down, close the outlet valve when the housing is loose, and remove the filter housing.
3. Change the filter housing o-ring annually and use only silicone lubricant (never vaseline).
4. Clean and wipe off the filter housing threads, on the housing and inside the head, at every filter change, and never lubricate the threads.5. Clean and sanitize filter housings whenever changing filters. Simply wipe out the filter housing, add a small amount of household bleach (tablespoon), rinse the housing out, and install a new filter cartridge.
6. When tightening the filter housing "never use a filter wrench". Hand-tighten the housing only to seat the o-ring. Using the wrench will flatten the O-ring causing it to leak and make even harder to get the housing off next time.
7. When replacing the filter leave the water valve on the outlet side of the filter off. Turn the water on slowly to the filter housing while holding down the pressure relief valve to release the air from the filter housing until all air is released then open the incoming water valve all the way. If there is no pressure relief button open a laundry tub faucet while turning the water back on to the filter to bleed the air off.
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| 4" x 10" Big Blue Housing with a red pressure relief button. |
There is also another class of whole house sediment filters commonly known as a Rusco or Blow Down filter. These filters have a screen inside to filter sediment, sand, and debris from wells. These types of water filters can be cleaned by opening a valve at the bottom and "blowing down" the filter periodically. Every 2- 3 months normally. These filters are a frequent choice for well drillers when sand is a problem coming from a well.
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| Rusco blow-down filter |
*Warning: Never use a cartridge filter for drinking water on a non-potable water supply.
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| A small sample of filter housings and cartridge filters are available. |
When installing a filter housing, for any purpose, it should always be mounted securely to a wall for ease of changing filters and to protect the plumbing along with shutoff valves before and after to isolate the housing when changing filters. Some filter housings incorporate a built-in shutoff on top and a pressure relief valve to aid in the filter housing removal and filter change.
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| A properly installed prefilter housing before a water softener |
In our next blog regarding "Water Filters", we will discuss whole-house filtration systems using backwashing filters and automatic regenerating filter systems to remove everything from sediment to iron, odor, arsenic, radium, and more.
I wish you, Good Days and Good Water!
Ray McConnell,
The Water Softener Blog
Below are links related to the topics discussed in this blog article;
