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347
A
S AVE THESE INSTRUCTIONS
(347IO) SPA ENGLISH 7.5” X 10.3” PANTONE 295U 07/08/2020
English
Page 20
SPA WATER CHEMISTRY AND BALANCE (continued)
Calcium Hardness (CaCO
3
):
refers to the amount of calcium and magnesium dissolved in the water.
Result if too low – Difficulty balancing water, corrosion of metal components, eye & skin irritation and water
foaming.
Result if too high – Scale formation, cloudy water, eye & skin irritation, difficulty balancing water and filter/
heater inefficiency.
Saturation Index (SI):
temperature, calcium hardness concentration, total alkalinity and pH represent the
main factors influencing scale formation. The tendency of water to either form scale or corrode is indicated by
the Saturation Index (SI):
SI = pH+TF+CF+AF-12.1
*Where: TF = Temperature Factor; CF = Calcium Hardness Factor; AF = Total Alkalinity Factor
Water Temperature
TF
Calcium
Hardness (ppm)
CF
Total
Alkalinity (ppm)
AF
(ºC)
(ºF)
8
46
0.2
75
1.5
50
1.7
12
54
0.3
100
1.6
75
1.9
16
61
0.4
150
1.8
100
2.0
19
66
0.5
200
1.9
150
2.2
24
75
0.6
250
2.0
200
2.3
29
84
0.7
300
2.1
300
2.5
34
93
0.8
400
2.2
400
2.6
40
104
0.9
500
2.3
--
--
Test the water pH, Temperature, Calcium Hardness and Total Alkalinity levels. Use the equivalent Factors in
the SI equation.
SI = 0, Balance
If SI > 0, Scaling or cloudy water condition.
If SI < 0, Corrosive to metals or eye & skin irritating condition.
The SI is considered satisfactory if the value is within -0.3 to +0.3 range. Zero being perfect.
WARNING
Handle all chemicals with care and wear extra personnel protective equipment
including goggle and gloves. It is very important not to splash acid onto your skin
or clothing, or into your eyes.
SPA Water Adjustment
How to adjust the spa water chemistry when the levels are off the range.
CAuTION:
Always follow the
chemical manufacturer’s directions, and the health and hazard warnings.
Total Alkalinity (TA) Adjustment
Remove the spa cover to aerate the water and use the included test strips to check the chemistry level.
Ensure the chlorine level in the water is between 2-4 ppm first, as chlorine will affect the TA test result.
If the TA level (and not the pH) is higher than 120 ppm, add appropriate chemical product to lower the TA
level.
If the TA level is lower than 60 ppm, add appropriate chemical product to raise the TA level.
NOTE:
After adjustment, retest the water after 24 hours and adjust again if necessary.
pH Adjustment
After the total alkalinity has been lowered to 120 ppm or raised to 80 ppm and the pH is still high or low, add
appropriate chemical product to adjust the pH level between 6.8 and 7.6.
Calcium Hardness Adjustment
Use the included test strips to check the water hardness level and adjust it with appropriate chemical product.