ETi 400 High Efficiency Pool and Spa Heater Installation and User’s Guide
Rev. A 9/2016
56
CHEMICAL BALANCE
(continued)
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 7 below.
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 7 below.
If pH becomes too high (over alkaline), it has these effects:
1. Greatly lowers the ability of chlorine to destroy bacteria and algae.
2. Water becomes cloudy.
3. There is more danger of scale formation on the plaster or in the heat exchanger tubing.
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 recirculation system, which may create brown, blue, green, or sometimes almost
black stains on the plaster.
4. If you have a sand and gravel filter, the alum used as a filter aid may dissolve and pass through the filter.
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 or 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.
WATER CHEMISTRY PARAMETERS
Section 4: Maintenance and Care
Table 7.
*
Start-up TDS includes source water TDS and any other inorganic salt added at start-up.
NOTE (**): Failure to adhere to the listed water chemistry parameters may result in premature failure of the heat exchanger and will
void the warranty.
Disinfectant levels
Minimum
Ideal
Maximum
Free Chlorine, ppm
1.0
2.0-3.0
4.0**
Salt, ppm
2000
3200
5000
Combined Chlorine, ppm
None
None
0.2
Bromine, ppm
2.0
4-6
10.0
Other Sanitizers
Levels not established. Consult local health department before use.
Chemical Values
pH
7.2
7.4-7.6
7.8**
Total Alkalinity (Buffering), ppm
60
80-100
180
as CaCO3
Salt ppm
2000
3200
5000**
Total Dissolved Solids, ppm
N/A
N/A
1,500 ppm > TDS at startup*
Calcium Hardness, ppm, as CaCO3
150
200-400
500-1,000
Heavy Metals
None
None
None
Biological Values
Algae
None
None
None
