Introduction; Water Chemistry - IPS Controllers M790 Owner's Manual

M790 pH/ORP Controller Owner's Manual
I. Introduction
A. Water Chemistry
Water chemistry is a complex science that contains many variables.
These variables not only affect the water environment itself, but
they can have adverse effects on your equipment as well as your
health. These are only some of the factors which we follow closely
to ensure the most healthy water interactions:
pH is the measurement of the acidity or basicity in an aqueous
solution. A measurement below 7 is considered acid, while a
measurement above 7 is base or alkaline. It is a significant factor
in determining the water quality as it affects sanitizer levels, water
color, and human reaction to the water.
ORP (Oxidation Reduction Potential) is the measurement of the
oxidizing capacity present in water. ORP cannot be fooled by the
effects of pH, total dissolved solids (TDS), stabilizers, and non-chlo-
rine oxidizers. A typical ORP sensor measures Hypochlorous Acid
(HOCI), which is the more effective component of free chlorine. A
higher ORP reading equates to the sanitizer working more effec-
tively.
Water balance is comprised of pH, calcium hardness, total alkalin-
ity, temperature, and TDS. When water is balanced, the Langelier
saturation index is 0. Values above +0.3 lead to scaling and cloudy
water, while values below -0.3 can cause corrosion of pool equip-
ment and surfaces. If the water balance is not fixed in a timely
manner, secondary effects can lead to rapidly declining water con-
ditions that can affect the health of the water occupants.
pH and ORP work conversely to one another, and are affected by
other factors such as temperature and TDS' that can increase the
negative impacts of unbalanced water.
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