Aquacal DIG-220, Owner'S Manual

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25
REFERENCE SECTION
CHEMICAL IDEAL
RANGE
IDEAL TEST
SCHEDULE
EFFECT OF LOW/HIGH LEVELS CORRECTIVE ACTIONS
Low free chlorine: Not enough residual chlorine to safely
sanitize pool water.
Low free chlorine: Check for combined chlorine level and shock
as necessary. Increase purifier output to maintain a 1-3 ppm
residual reading.
Free
Chlorine
1 to 3 ppm Weekly
High free chlorine: Corrosive to metallic fixtures in pool water.
Can bleach swimwear and hair.
High free chlorine: Decrease purifier output. Let chlorine
dissipate normally until 1-3 ppm is achieved. In extreme
cases, pool water can be diluted with fresh water or a chlorine
neutralizer added. (Diluting will reduce salt and CYA. Check
and adjust as needed.)
Low pH: (acidic) Equipment corrosion, eye/skin irritation,
plaster etching, rapid chlorine consumption.
Low pH: Add sodium carbonate or soda ash
Ph
7.2 to 7.8
ppm
Weekly
High pH: (basic) Scale formation, cloudy water, eye/skin
irritation, poor chlorine effectiveness
High pH: Add muriatic acid or sodium bisulfate.
Low TA: Eye irritation, pH "bounce", stained/etched plaster
and metal corrosion.
Low TA: Add sodium bicarbonate.
Total
Alkalinity
80 to 100
ppm
Monthly
High TA: Constant acid demand, difficulty in maintaining pH,
and contributes to scale formation or cloudy water conditions.
High TA: Add muriatic acid often, a little at a time (may take a
week or more to lower the TA).
Low Salt: Below 2,500 ppm causes premature cell failure and
reduces chlorine production
Low Salt: Add salt according to digital display on Pool Pilot
unit or salt chart.
Salt
3000 to 4 500
ppm
Monthly
High Salt: Above 6,000 ppm can cause corrosion of metallic
fixtures and will taste salty. Note: DIG-220 can safely operate
with salt levels up to 35,000.
High Salt: If undesirably high, partially drain and refill the pool
with fresh water. (Diluting will reduce CYA. Check and adjust
as needed.)
Low CH: Etching of plaster, equipment corrosion Low CH: Add calcium chloride flakes.
Calcium
Hardness
200 to 400
ppm
Monthly
High CH: Scale formation, cloudy water. Rapid buildup of
scale may exceed the system's self-cleaning capability
and require manual cleaning of the c ell.
High CH: Partially drain and refill pool with fresh water to
dilute. (Diluting will reduce salt and CYA. Check and adjust as
needed.)
Please note – in some areas there may be higher than
recommended calcium levels in the tap water. If this level is
seen, call the factory for advice on this condition.
Cyanuric
Acid (CYA)
- Stabilizer -
60 to 80 ppm
30 to 50 ppm
Monthly Low CYA: destruction of chlorine by the UV rays from the sun.
High CYA: Requires more chlorine to maintain proper sanitizer
levels.
Note: CYA not needed for indoor or bromine pool.
CYA can be reduced to 30 - 50 ppm for DIG-220 in colder
climate regions.
Low CYA: Add cyanuric acid(1 lb/5000 gallons increases CYA
25 ppm)
High CYA: Partially drain and refill pool with fresh water to
dilute. (Diluting will reduce salt. Check and adjust as needed.)
Basic Water Chemistry Continued:
Using the Saturation Index (SI):
The Saturation Index is a formula used to predict the calcium carbonate saturation of water, that is, whether your water wil l precipitate, dissolve, or be in equilibrium with
calcium carbonate.
Water is properly balanced if the SI is 0 ± 0.3. If SI is greater than 0.3, scaling and staining will occur. If SI is les s then -0.3, the water is corrosive to metallic fixtures an d
aggressive to plaster surfaces and vinyl liners.
A high or low SI can cause premature damage to the cell, equipment or pool finish. As a general rule, higher concentrations
of calci um, total dissolved solids, pH, and
alkalinity all promote a greater tendency for scale. Scaling potential also increases with increasing temperature.
Use the chart below to determine your overall water balance. Test water for pH, water temperature, Calcium Hardness, Total Alkalinity, Salt Level, and use the equivalent Factors
(TF, CF, AF, Constant) from the chart below to determine your Saturation Index. Adjust chemicals to maintain balanced water.
TF
Calcium
Hardness
CF
Total
Alkalinity
AF
Salt Level
SC
60 F 15.6C 0.4 150 ppm 1.8 75 ppm 1.9 0 - 1000 ppm 12.1
66 F 18.9C 0.5 200 ppm 1.9 100 ppm 2.0 1001 - 2000 ppm 12.2
76 F 24.4C 0.6 250 ppm 2.0 125 ppm 2.1 2001 - 3000 ppm 12.3
84 F 28.9C 0.7 300 ppm 2.1 150 ppm 2.2 3001 - 4000 ppm 12.4
94 F 34.4C 0.8 400 ppm 2.2 200 ppm 2.3 4001 - 5000 ppm 12.5
103 F 39.4C 0.9 600 ppm 2.4 250 ppm 2.4 5001 - 6000 ppm 12.6
Temperature
pH + TF + CF + AF - SC = SI
-.3 -.2 -.1 0 .1 .2 .3
Corrosive to
metals, etches
plaster
finishes, and
irritates skin
OK
Scaling,
staining, and
cloudy water
conditions