How to Sanitize a Commercial Pool

A commercial pool chlorinator consists of a plastic vessel that holds chlorine tablets and has a valve to control the flow of chlorinated water to the pool. The chlorinator is dependent upon the pool's circulation pump to dispense chlorine and will not feed chlorine into the pool if the pump is off. When the pump is running, the chlorinator will run automatically. A check valve should be installed with a commercial pool chlorinator to prevent back flow of chlorinated water to other pool equipment. A check valve is particularly important to protect heaters which can be damaged by chemicals. We carry Rainbow commercial pool chlorinators made by Pentair so these will be models discussed below.

Commercial pool chlorinators are rated as "high capacity" due to the greater number of tablets they hold and the larger size pools they're designed to sanitize. There are four main Rainbow high capacity chlorinators, three of which are "inline" meaning they are plumbed directly inline with the hard plumbing for the pool. These inline units are designed for 1" hard plumbing installations. There is also one "offline" unit which uses tubing to tap into the hard plumbing; the tubing is connected to holes drilled into the pipe. One inch or three inch tablets may be used. The inline units can also be used with bromine but the maximum number of gallons is lower.

The smallest inline commercial unit is the HC-3315 which holds 15 lbs of chlorine tablets and can treat pools up to 97,000 gallons. If treating with bromine, the HC-3315 will treat up to 20,200 gallons. To give you an idea of size, the small unit is 21-1/2 in H x 8 in W x 15 in D.

The next size up is the HC-3330 commercial chlorinator which can hold 30 lbs of chlorine tabs, treating pools up to 160,000 gallons. With bromine, it will treat up to 40,000 gallons. The HC-3330 is 39-1/8 in H x 8 in W x 15 in D.

The largest of the three inline Rainbow commercial chlorinators is the HC-3340 which holds 40 lbs of tablets. It will treat up to 332,000 gallons with chlorine and up to 61,000 gallons with bromine.

The offline commercial chlorinator is the 300-29X. It will hold 29 large or 237 small trichlor tablets and dispenses 8.5 lbs of 1" tabs in 24 hours. The Rainbow 300-29X will treat pools 80,000 to 322,000 gallons.

These automatic chlorinators offer a number of advantages. They are a convenient and inexpensive way to sanitize commercial pools. They require no electrical connection at the pool, other than the already existing pool pump, and are relatively easy to install. A dial on the chlorinator allows you to adjust the amount of chlorine dispensed. For maintenance and repair, replacement parts for automatic commercial chlorinators are readily available.

Another option for sanitizing a commercial pool is a salt chlorine generator. Increasingly popular for residential pools, a few manufacturers, namely Auto Pilot and Pentair, also make commercial pool salt systems. These systems use salt added to the pool water to create chlorine. They are comprised of a power supply which would be wired to the electrical supply for the pool equipment and a cell which is plumbed inline with the hard plumbing. Commercial systems typically have multiple cells in order to produce enough chlorine for the greater volume and bather load of commercial pools. Depending on the brand and system, commercial salt chlorine generators can produce from 4 to 32 lbs of chlorine daily.

Here are the basics of how a salt chlorine generator works. Fine solar salt (99% NACL) is added to the pool water; quantity will be based on the pool volume. It is worth noting that the amount of salt added is below the threshold where a swimmer would actually taste salt. A pool with a salt chlorine generator has nowhere near the parts per million of salt that you would find in sea water. Water flows through the cell where the salt reacts with the coating on the blades inside the cell to create chlorine. This chlorinated water then flows back into the pool. Because salt does not evaporate, it remains in the pool and the same salt originally added continues to produce chlorine. This form of chlorine has none of the chloramines which cause standard chlorine to have that bleach smell. It is less harsh to skin, eyes and bathing suits and will not turn anyone's hair green which makes it a safer and much more pleasant sanitizer.

At the power center, you can monitor the salt level and make adjustments as needed. If heavy rains dilute the pool water or there is a loss of water, salt might need to be added to get back to the recommended parts per million. The power supply also has a "super chlorinate" feature which allows you to shock the pool using the salt system.

Commercial salt chlorine generators greatly reduce the expense of buying chemicals, eliminate chlorine storage, and provide a healthier form of chlorine. They are compatible with ORP controllers to help maintain proper chemical levels. Digital displays make it easy to monitor salt levels, cell cleanliness, sanitizer output and water flow. The main drawbacks of commercial salt chlorine generators is the initial expense and installation, and the eventual need to replace the cells.