3.2.0 Automatic Backwash Filters
The most trouble free, automatic type of filter to remove iron and sulfur
is an automatic backwash type water filter. The standard filters are manufactured
to accommodate residential and small commercial needs. The filters are identical
to water softeners with the exception that the softener resin is replaced
with a different media.
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3.2.1 Iron & Sulphur Filters
Magnesium greensand or similar media is used for the iron & sulphur filter.
Types of contamination iron & sulfur filters can remove are red water
iron and clear water iron. These are the most common iron contaminations
and are the major cause for rusty water that stains clothing and fixtures.
Other contaminates besides iron are manganese, sulphur, dirt, and other suspended
matter. The iron & sulphur filter can remove up to 10 to 12 parts per
million of red or clear water iron depending on manufacturer and size of
filter.
A quick and dirty test other than having your water tested is to run the
water through a white cloth rag and see if the water stains the rag orange.
Another indication of a red or clear water iron is to put raw water from
your system in a container and see if it has turned the pan orange inside
after setting for a few hours.
The easiest way to get your water tested is to take a sample to your local
county health department. A second way to get your water tested is to have
a water softener sales person visit you to test your water and give you a
sales pitch. If you have two to three hours and a few hundred dollars to
a few thousand dollars extra to spend on a filter system have a water softener
sales person sell you a system. Otherwise get the parts and have a handy
friend help you put it in. If you get into trouble, you can always hire a
plumber to untangle the system. At least you can save some cost of the labor
and the profit markup on the system.
The automatic backwash filter eliminates the need to change filters as most
in line cartridge filters require.(See Figure 2) The only catch is that some
require a chemical to be put into a chemical tank. This tank is similar to
the brine tank on a water softener system except that it is much smaller,
typically 5 gallons. The chemical used in these type of tanks is Potassium
permanganate, a deadly poison. The iron filter uses the chemical to attract
the iron in the filter to itself and is then backflushed from the media during
a regeneration cycle.
Figure 2 - Smaller Backwash Type Iron Filter
Regeneration cycle times are dependant on the amount of suspended matter
in your water supply and the type of regeneration control on your filter.
Most filters as well as water softeners have Time-Clock controls while the
more sophisticated controls are metered. The Time-Clock control regenerate
the system on intervals (typically a fixed amount of chemical is used to
regenerate the filter media) every certain number of days. Metered systems
regenerate based on number of gallons used. This is the best regeneration
system control, however, is seldom offered with an Iron & Sulfur filter.
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3.2.2 Automatic Chemical Feeder
The iron filter in most cases comes with an automatic chemical feeder.(See
Figure 3) This feeder is very similar to the brine tank on a water softener
system except that it is smaller. Most feeder tanks hold a total of 5 gallons
liquid capacity and a 30 pound Potassium Permangante capacity. For safety
reasons, the feeders covers are attached with screws. This is to prevent
children and pets from getting into them.
Figure 3 - Backwash Iron Filter with Chemical Feeder Tank
The system typically includes a drain tube, suction tube, and have an overflow
fitting on them. When purchasing ask if the system you are purchasing has
these items. You could end up purchasing them when you should have received
them with the system.
One source for iron filters via the Internet is
GOODH2O. They
sell the lowest cost water softener products
on the internet that I've found.
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3.2.3 Potassium Permanganate
The chemical compound used to regenerate iron and sulfur filters is Potassium
Permanganate. This mixes with water to regenerate the iron filter. Each
manufacturer of iron & sulfur filters has specific recommendations on
the amount of chemical you need to regenerate your particular system. The
chemical bottles also have information concerning the recommended amount
of chemical for correct treatment and economy.
 WARNING: POTASSIUM
PERMANGANATE used to regenerate iron filters is a POISON.
 Use extreme care when handling
this chemical.
Potassium Permanganate is a very corrosive chemical. Care must be used when
using this chemical. Read the caution labels very carefully. Should your
water ever turn pink to red to deep purple in color, do not drink the water.
Potassium Permanganate can be toxic. Have your unit checked by a plumber
should your water change to pink to deep purple in color.
An OSHA Hazard Communication Standard and Material Data Sheet (MSDS) can
be obtained from chemical suppliers. The MSDS can provide you with additional
information concerning the use and safety aspects of this chemical compound.
Don't be afraid to ask for the MSDS data sheet, most corporate buyers will
not even purchase a chemical from a supplier without the data sheet so most
suppliers will give you one as a matter of course in doing business.
Note: It is not recommended to try using potassium permaganate to get the
rust out of anything. It does not cause the rust to become suspended like
other rust removal products. As I stated in Section 2.2.1, the chemical attracts
the iron to it from the filter media. If you get the chemical on anything
from the backwash cycle, it will be end up either very purple, very rust
orange, or a combination of both depending on what part of the regeneration
cycle the backwash comes from.
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3.3 Taste & Odor Removal Filter
3.3.1 Carbon Filter
The iron & sulphur filter is not good for removal of organic iron or
matter. To remove organic matter, musty odors, or chlorine tastes, a highly
activated carbon filter should be used. The larger, household size filters
are identical to the iron & sulfur filter in appearance and installation
except the filter media. These filters do not require chemicals to regenerate.
The bad news is that this filter will not remove sulphur odor, red water
iron, or clear water iron.
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3.4 Lead Filter/Heavy Metals
If your water tests positive for lead or what is termed as a heavy metal,
there are in line filters designed to remove the contamination(See Figure
4). The filters are typically one time use and can filter up to 5,000 gallons
of water (or 1 year of service). They are typically installed in-line on
your drinking water line and cost between $45 and $90. Connection type and
size is dependant upon the manufacturer.
Figure 4 - Lead Removal Filter
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3.5 Water Softeners
There are two basic types of controls for water softeners. The control operates
the water softeners valve system. The older mechanical timer is the most
widely used and lowest cost water softener currently being sold. The timer
type softener regenerates at a regular, programmed interval. The timer is
typically set so the unit will regenerate during an off use time. The latest
type is a microprocessor controlled unit that regenerates based on the amount
of water you use. This is the lowest cost unit to operate, however, is more
expensive to purchase.
Water softeners come in two basic forms. One form is as an integrated unit
(See Figure 5). This is more for space savings and sold as a designer type
of softener. The other form of tank is the standard two tank system(See Figure
6). One tank contains the synthetic resin for the filter and the shorter
tank is the salt brine tank. The cost of a typical 24,000 grain system is
$ 400 to $ 500 dollars.
Figure 5 - Integrated Water Softener
Water softeners remove the hardness from water by attracting the minerals
in the water to a synthetic resin bed inside the water softener. The calcium
and magnesium ions are removed from the raw water by being attracted to the
resin. These ions are later removed from the resin when they are exchanged
for sodium ions from a brine solution during regeneration. The brine solution
is made from rock salt or salt pellets and water put into the brine tank
during the regeneration cycle. Salt pellets and rock salt are available at
local supermarkets and hardware stores.
Figure 6 - Typical Two Tank Water Softener
A water softener will remove up to 10 parts per million of iron and gets
a noticeable amount of iron out of the water. A problem arises when there
is to much iron for the water softener to get out. What occurs is the water
softener will stop softening once it has saturated with mineral ions. This
is what occurred with my system. Because my major contamination problem was
clear water iron, I put the iron filter in front of my water softener (Between
the well and water softener). This greatly reduced the regeneration cycle
times on my water softener and I even get softened water now.
One source for water softeners & iron filters via the Internet is
GOODH2O. They
sell the lowest cost water softener products
on the internet that I've found.
Tip: Some water softener manufacturer's claim they have a special bacteria
eliminating resin in the top of their units. This resin needs to be replenished
every year or so for great tasting water. The truth is that their claim is
somewhat true. Dumping a cup of laundry bleach through a regular
water softener (via the brine tank) every 3 months can kill bacteria as well
and costs less. As was pointed out by one "Water Conditioning
Professional" who is not happy with this publication (as it cuts into his
livelyhood), resins and bleach do not get along and if left in the resin
tank will destroy a number of manufacturer's resins.
If you really want the special bacteria eliminating resin, you could walk
into one of these manufacturer's dealers outlets and purchase the resin,
go home and take the top off your water softener and dump it in per their
instructions. If you can't get it all in, the next time you need to put some
more it (typically once a year), scoop enough off the top to get it all in.
I have never bothered to do anything with the resin
tank since this is, in a number of instances, just another means of
selling you something you neither need nor want. Unless there
is a problem with the system, I never open the resin tank, barring
a bacterial contamination of the well.
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Section 4.0 - Pipe
There are 4 types of pipe typically used around the country. They are PVC
(poly vinyl chloride), copper, lead, and black iron. Since lead pipe is a
health hazard and outlawed for use as a water pipe and black iron is only
in very old houses as well as rusts, I will be describing installations using
PVC and copper pipe.
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3.6 ph Filters
PH filters are used to raise the ph level to the neutral level. The filter
won't raise it any higher than that. Primary use of these systems is
to treats corrosive (acidic) water. Alkalinity and pH are increased
through processing. The way the residential units typically
work is that water passses through a granular calcite material (calcium
carbonite, marble or lime)
A mix of calcite and magnesium oxide can also be used if the water is very
acidic. If a higher flow rate is needed, a system to chemically feed soda
ash, sodium carbonate or caustic soda (sodium hydroxide) is sometimes. These
systems increase the sodium content of water, whereas using calcite or lime
increases calcium.
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4.1 PVC Pipe
Should PVC pipe be used for your plumbing, substitute plastic pipe for copper
tubing from the parts list and use PVC pipe adhesive instead of solder with
flux. Instead of soldering, the adhesive is applied to the PVC pipe and
assembled. PVC pipe and adhesive is available at most hardware stores and
plumbing outlets. Follow the manufacturers directions and wait times.
If preferred, you can still use copper pipe. The cost between copper and
PVC on a small job like a water filter installation is not much. The only
additional parts would be a pair of compression unions designed for PVC to
copper connections.
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4.2 Copper Pipe Soldering/Joint Sweating
The majority of homes in the United States have copper pipe. For that reason,
the installation instructions are written for sweating copper pipe joints.
This is typically done with a small inexpensive propane torch. These torches
are open flame devices. Use extreme care so you don't set anything on fire
or burn yourself. For your safety, have a fire extinguisher in the area when
doing the installation.
Figure 7 - Solder Fillet Detail
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4.3 Three Way Valve (3-way)
One of the key details to any installation is the installation of a three
way valve bypass. This valve configuration will allow you to bypass your
filter should you need to have work done on the system or you take the system
with you when you move. There are two ways to accomplish the valving. One
is to use a commercial bypass valve(See Figure 8).
Figure 8 - Commercial 3-way Bypass Valve
The second is to make your 3-way from three individual valves. If time is
money and ease of installation is important, the commercial 3-way valve is
the way to go. If you have time on your hands and want to save 25 to 30 percent
of the cost of the commercial valve, the three valve configuration is the
lowest cost way to go (See Figure 9).
Figure 9 - 3-way Valving Set-up
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Last Revised 1.30.09 |
