Rheem Raypak Hi Delta P902C Installation & Operating Instructions Manual page 24

Pool/Spa Water Chemistry
NOTE: Chemical imbalance can cause severe
damage to your heater and associated equipment.
Automatic Chlorinators and Chemical
Feeders
CAUTION:
Combustion
contaminated by corrosive chemical fumes which
can damage the heater and void the warranty.
All chemicals must be introduced and completely di-
luted into the pool or spa water before being circulated
through the heater. Do not place chlorine tablets or
bromine sticks in the skimmer. High chemical concen-
trations will result when the pump is not running (e.g.
overnight).
Chlorinators must feed downstream of the heater and
have an anti-siphoning device to prevent chemical
back-up into the heater when the pump is shut off.
NOTE: High chemical concentrates from feeders
and chlorinators that are out of adjustment will cause
very rapid corrosion of the heat exchanger in the
heater. Such damage is not covered under the
warranty.
Recommended Level(s)
Water Temperature
pH
Total Alkalinity (ppm)
Calcium Hardness (ppm)
Salt (ppm)
Free Chlorine (ppm)*
Total Dissolved Solids
(ppm)
*Free Chlorine MUST NOT EXCEED 5 ppm!
**In salt water chlorinated pools, the total TDS can be as high as 4500 ppm
NOTE: The allowable concentrations of salt and of the Total Dissolved Solids are lower for the Hi Delta than
for a typical residential pool heater, due to the higher water temperatures at which a Hi Delta operates.
air must not be
Fiberglass Pools
68-88°F (20-31°C)
7.3-7.4
120-150
200-300
3000 Maximum
2-3
1500 Maximum**
Table I: Water Chemistry
pH of Water
pH is a measure of relative acidity, neutrality or alka-
linity. Dissolved minerals and gases affect water's pH.
The pH scale ranges from 0 to 14. Water with a pH of
7.0 is considered neutral. Water with a pH lower than
7 is considered acidic. Water with a pH higher than 7
is considered alkaline. A neutral pH (around 7) is desir-
able for most potable water applications. Corrosion
damage and water heater failures resulting from water
pH levels of lower than 6 or higher than 8 are non-war-
rantable. The ideal pH range for water used in a
storage tank or a copper water heater system is 7.2 to
7.8.
Total Dissolved Solids
Total dissolved solids (TDS) is the measure of all min-
erals and solids that are dissolved in the water. The
concentration of total dissolved solids is usually ex-
pressed in parts per million (ppm) as measured in a
water sample. Water with a high TDS concentration
will greatly accelerate lime and scale formation in the
hot water system. Most high TDS concentrations will
precipitate out of the water when heated. This can
generate a scale accumulation on the heat transfer
surface that will greatly reduce the service life of a pool
heater. This scale accumulation can also impede ade-
quate flow of water and may totally block the water
passages in the tubes of the heat exchanger. A heat
exchanger that is damaged or blocked by lime/scale
accumulation must be replaced. Failure of a water
Fiberglass Spas
89-104°F (31-40°C)
7.3-7.4
120-150
150-200
3000 Maximum
2-3
1500 Maximum**
24
Other Pool and Spa
Types
68-104°F (20-40°C)
7.6-7.8
80-120
200-400
3000 Maximum
2-3
1500 Maximum**