Pentair HP 800 Heat Pump User Manual


 
24
COMMERCIAL FEEDERS
We strongly suggest that all chemical feeders be placed "down line" of the heater. In a "closely monitored"
commercial pool situation where a vacuum type filter system is used in conjunction with a surge tank, there are
some exceptions to chemical injection. Some liquid chlorine (sodium hypochlorite) feeders and liquid muriatic
acid feeders will inject their solutions into the surge tank on the suction side of the unit. You may inject diluted
liquid chlorine and muriatic acid as long as each are diluted with 75 % water in the supply tank. The feeders must
be adjusted to a slow enough rate to prevent the water in the surge tank from dropping below 7.6 pH and or chlorine
levels above 5 p.p.m. You can test the surge tank water while the feeders and circulation pump is running just as
you would the pool water. Then adjust the solution or rate of feed accordingly. The circulation pump usually
moves the water through the surge tank rapidly enough to keep chemical concentrations down. Never place
chlorine tablets in the surge tank.
Also note: Electric type feeders must be electrically relayed to the circulation pump, so the feeders will shut
off when the pump does.
CHEMICAL APPLICATION FOR SPAS
Spas require some special attention due to their small water volume and high heat compared to a normal swim-
ming pool. A spas water balance fluctuates more rapidly than a pool. The following are suggestions that we feel
will prolong the life of the heat exchanger used for a spa heater.
1. Test the water frequently to prevent drastic fluctuations in pH and sanitizer levels especially after usage. Keep
total alkalinity at 100 p.p.m. to 120 p.p.m.
2. Spas react quickly to chemicals when added. Use small amounts and retest the water until you reach the desired
chemical values.
3. Some chlorine tablets are very acetic and will lower the pH of the spa water as the solution is fed. Make sure the
spa water does not drop below 7.4 pH, see page 20 and 21 for more information.
4. Bromine has a more neutral pH value and works well in spa water if pH is maintained at 7.8-8.0. It is a form of
chlorine widely used for spas. Do not install a brominator on the suction side of the filtering system.
5. Using muriatic acid right from the bottle at the same strength as packaged may drastically lower the pH
uncontrollably. There are some dry powdered forms of acid that work better for spas and are somewhat milder and
are easier to handle.
6. All the same rules of chemical application and chlorinator placement that apply in the previous chemical section
also apply to spas. Always consult a professional pool builder or service and follow the chemical manufacturers
directions.
WARNING
Working with muriatic acid can be dangerous. When cleaning elements always
wear rubber gloves and eye protection. Add acid to water, do not add water to
acid. Splashing or spilling acid can cause severe personal injury and/or property
damage.