Chemical Balance; Pool And Spa Water - Pentair MiniMax 75 Operation & Installation Manual

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CHEMICAL BALANCE

POOL AND SPA WATER

Your Pentair Water Pool and Spa pool heater was
designed specifically for your spa or pool and will give
you many years of trouble free service provided you keep
your water chemistry in proper condition.
Three major items that can cause problems with your
pool heater are improper pH, disinfectant residual, and
total alkalinity. These items, if not kept properly balanced,
can shorten the life of the heater and cause permanent
damage.
WARNING
Heat exchanger damage resulting from chemical
imbalance is not covered by the warranty.
WHAT A DISINFECTANT DOES
Two pool guests you do not want are algae and bacteria.
To get rid of them and make pool water sanitary for
swimming - as well as to improve the water's taste, odor
and clarity - some sort of disinfectant must be used.
Chlorine and bromine are universally approved by health
authorities and are accepted disinfecting agents for
bacteria control.
WHAT IS A DISINFECTANT
RESIDUAL?
When you add chlorine or bromine to the pool water, a
portion of the disinfectant will be consumed in the process
of destroying bacteria, algae and other oxidizable
materials. The disinfectant remaining is called chlorine
residual or bromine residual. You can determine the
disinfectant residual of your pool water with a reliable
test kit, available from your local pool supply store.
You must maintain a disinfectant residual level adequate
enough to assure a continuous kill of bacteria or virus
introduced into pool water by swimmers, through the air,
from dust, rain or other sources.
It is wise to test pool water regularly. Never allow
chlorine residual to drop below 0.6 ppm (parts per million).
The minimum level for effective chlorine or bromine
residual is 1.4 ppm.
pH - The term pH refers to the acid/alkaline balance of
water expressed on a numerical scale from 0 to 14. A test
kit for measuring pH balance of your pool water is available
from your local pool supply store; see Table 1. Muriatic
Acid has a pH of about 0. Pure water is 7 (neutral).
Weak Lye solution have a pH of 13-14.
RULE: 7.4 to 7.6 is a desirable pH range. It is essential
to maintain correct pH, see Table 2.
P/N 471105
If pH becomes too high (over alkaline), it has
these effects:
1. Greatly lowers the ability of chlorine to destroy
2. Water becomes cloudy.
3. There is more danger of scale formation on the plaster
4. Filter elements may become blocked.
If pH is too low (over acid) the following
conditions may occur:
1. Excessive eye burn or skin irritation.
2. Etching of the plaster.
3. Corrosion of metal fixtures in the filtration and
4. Corrosion of copper in the heater, which may cause
5. If you have a sand and gravel filter, the alum used as
CAUTION: Do not test for pH when the chlorine
residual is 3.0 ppm or higher, or bromine residual is
6.0 ppm or higher. See your local pool supply store
for help in properly balancing your water chemistry.
RULE: Chemicals that are acid lower pH. Chemicals
that are alkaline raise pH.
ALKALINITY High - Low:
"Total alkalinity" is a measurement of the total amount of
alkaline chemicals in the water, and control pH to a great
degree. (It is not the same as pH which refers merely to
the relative alkalinity/acidity balance.) Your pool water's
total alkalinity should be 100 - 140 ppm to permit easier
pH control.
A total alkalinity test is simple to perform with a reliable test
kit. You will need to test about once a week and make
proper adjustments until alkalinity is in the proper range.
Then, test only once every month or so to be sure it is being
maintained. See your local pool dealer for help in properly
balancing the water chemistry.
Compliments of www.poolsandstuff.com
bacteria and algae.
or in the heat exchanger.
recirculation system, which may create brown, blue,
green, or sometimes almost black stains on the
plaster.
leaks.
a filter aid may dissolve and pass through the filter.
pH Chart
Table 1.
Strongly Acid Neutral
0 1 2 3 4 5 6 7
pH Control Chart
Table 2.
6.8 7.0 7.2
Add Soda Ash or
Marginal
Sodium Bicarbonate
Maintenance (contd.)
Strongly Alkaline
8 9 10 11 12 13 14
8.0 8.2 8.4
7.4 7.6 7.8
Ideal Marginal Add Acid
Rev. H 10-16-07