Table of Contents
Advertisement
Page 18
3D. Water Chemistry
3D-1. Pools
The mineral content of swimming pool water
increases daily, due to natural evaporation and the
addition of sanitizing chemicals. If the mineral
concentration in the pool gets too high, the excess
minerals will deposit on the walls of the pool, in the
fi lter system, and in the heater tubes. It is important
to keep the pH factor of the pool water between 7.4
and 7.6. See Table 7 for guidelines on other chemical
measurements.
3D-2. Spas
The proper chemical balance in spa water is more
critical than in a swimming pool heater operation. Due
to the spa's size, high water temperature, and heavy
usage, chemical values in a spa can vary greatly. This
chemical imbalance can result in unsanitary water
conditions, and affect the life of the heater.
3D-2a. Spa Water Chemistry
Maintaining safe water conditions in a spa can
only be done by regular water changes and the proper
addition of sanitizing chemicals. Kits are available
from your local pool supply dealer for making the
various tests for mineral content. One of these kits will
detect copper in the system. This is usually a warning
that corrosion is taking place, possibly due to a low pH
value combined with other chemistry problems. The
condition can be corrected by changing the spa water
and closely monitoring the pH factor and chemical
properties of the water (see Table 7).
Test
Free Chlorine or
Total Bromine
pH
Total Alkalinity (TA)
Calcium Hardness (CH)
Langelier Saturation Index (SI)
Cyanuric Acid
Total Dissolved Solids (TDS)
Copper
*As recommended by IPSA
Table 7. Chemical Concentration Levels.
3D-2b. Water Changing
Jandy Pool Products, Inc. recommends changing
of spa water every 60 days if usage is light and every
30 days during heavy usage. Be sure to stabilize the
water chemistry after every water change.
Recommended
Level*
1.0 to 3.0 ppm
2.0 to 4.0 ppm
7.2 to 7.6
100 to 150 ppm
200 to 400 ppm
-0.5 to +0.5
30 to 150 ppm
Less than 1500 ppm
0 ppm
3D-2c. Corrosion
The corrosive action of pool/spa water is
increased by the following:
1. Low pH - acidity
2. Low Total Alkalinity - bicarbonates
3. Low Calcium hardness - soft water
NOTE: Jandy does not warrant heat exchangers
damaged by corrosive water.
3D-2d. Testing
Jandy Pool Products, Inc. recommends that
spa owners purchase a test kit and use it regularly. A
minimum kit is one which will measure chlorine and
pH levels.
The pool/spa owner will fi nd it helpful to have
a qualifi ed professional technician perform more
extensive chemical testing and water changing on a
regular basis.
3E. Spa/Hot Tub Safety Rules
The following "Safety Rules for Hot Tubs,"
recommended by the U.S. Consumer Product Safety
Commission should be observed when using the spa:
1.
Spa or hot tub water temperature should never
exceed 104°F (40°C). A temperature of 100°F
(38°C) is considered safe for a healthy adult.
Special caution is suggested for young children.
2.
Drinking of alcoholic beverages before or during
spa or hot tub use can cause drowsiness which
could lead to unconsciousness and subsequently
result in drowning.
3.
Pregnant women beware! Soaking in water above
102°F (39°C) can cause fetal damage during
the fi rst three months of pregnancy (resulting
in the birth of a brain-damaged or deformed
child). Pregnant women should stick to the 100°F
(38°C) maximum rule.
4.
Before entering the spa or hot tub, users should
check the water temperature with an accurate
thermometer; spa or hot tub thermostats may err
in regulating water temperatures by as much as 4
degrees Fahrenheit (2°C).
5.
Persons with medical history of heart disease,
circulatory problems, diabetes or blood pressure
problems should obtain their physician's advice
before using a spas or hot tubs.
6.
Persons taking medications which induce
drowsiness, such as tranquilizers, antihistamines,
or anticoagulants should not use spas or hot tubs.
Prolonged immersion in hot water can induce
hyperthermia. Hyperthermia occurs when the internal
Advertisement
Table of Contents
