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Winterizing Your Pool

Winterizing your pool protects it from damage by chemical imbalance and algae growth. A properly winterized pool is securely covered and, thus, protects little ones from drowning.

Many people believe that pool equipment can be can be shut down during winter months. This may be true in certain areas of the country where temperatures dip below freezing for a good part of the time, but the lack of circulation can allow algae to grow in a pool in a more moderate climate. Thus, if you live in warmer weather, you should run your equipment every day. However, you don't need to run it for as long a period each day. Reduce your timer to about half the time that you operate your equipment during swim season.

What's more, draining a pool is a no-no that can cause significant damage to the pool. The weight of the water actually keeps the pool from rising out of the ground. Emptying the pool can allow pressure to push the pool and surrounding decking out of the ground in a matter of days, causing thousands of dollars in damage.

If you do live in a cold climate and don't plan to operate the equipment during the winter, the first step in preparing your pool for the off-season is to test your pool water to protect the pool from staining, scaling, and equipment damage. You can do this using a test kit, or it can be done on site by a pool maintenance professional. A third alternative is to bring a water sample into your local pool and spa supply company to be tested by a pool water professional. If the test reveals metal or calcium problems, follow the chemical treatment directions of your pool water professional.

Here's the quick once over when it comes to winter and pool water. If necessary, raise the total alkalinity to 80 to 125 parts per million (ppm) for plaster pools or 125 to 150 ppm for vinyl, painted, or fiberglass pools. With respect to pH, tests should show a pH of 7.4 to 7.6. Use acid to lower the pH or a pH increaser, such as soda ash (sodium carbonate), to raise the pH.

If necessary, raise the calcium hardness to 200 to 250 ppm for plaster pools and 175 to 225 for all others or as recommended by your pool water professional.

Prior to closing or covering the pool for the season, the pool walls and bottom should be brushed and vacuumed to remove any debris that could cause staining. Calcium and hard water stains at the water line tile should be removed. Remove all debris from skimmer baskets, the pump strainer basket, and the automatic pool cleaner, if one exists. Thoroughly clean the filter by backwashing the system or cleaning the cartridge in the case of a cartridge filter.

Never store a dirty filter. Deposits and scale may harden and cake over the winter leaving a tough repair or clean up job in the spring.

The pool should be super chlorinated for the winter to protect against unwanted bacteria. In addition, the filter pump should be run for several hours to thoroughly distribute the chlorine. If you own a pool with a plaster finish, you might want to consider using a chlorinating floater that contains chlorine tablets.

When the pump and filter are not operating, any algae present in your pool water has a chance to run wild. To prevent this, add an algaecide directly to the water around the edges of the pool. Run the pump and filter to circulate the water and to distribute the algaecide.

Extra precautions should be taken if your pool is located in an area that frequently reaches sub-zero temperatures. Damage due to frozen pipes can be avoided by partially draining the pool to about 4 inches below the skimmer. When in doubt, follow the advice of your pool builder or local pool water professional.

Other "cold climate" precautions include draining the heater manifold, strainer basket and pump, and the solar heating system (if one exists). The heater manifold is a distributor of sorts. It directs the unheated pool water into the heat exchanger (where the water is heated), back into the manifold and out to the pool or spa. The manifold can be drained by opening a small drain valve located on the heater housing or on the manifold itself. Refer to owner's manual for drain valve location.

Also, the skimmer expansion plug should be used to plug one or more pipes at the bottom of a skimmer. The skimmer expansion plug is a rubber plug with a wing nut at the top. Tightening the wing nut will cause the plug to expand for a secure fit in the pipe opening at the bottom of the skimmer. The plug is designed to prevent water from getting into the pipe at the bottom of the skimmer and freezing which could prevent damage.

Finally, cover the pool to keep leaves and other debris out. Consult the Consumer Products Safety Commission (CPSC) for an approved cover that can prevent children and animals from drowning.

Much of what we have suggested regarding winterization is not required (or recommended) for pools located in mild climates. Instead of closing the pool, chemical treatment and filtration can be scaled back if you don't plan to use the pool during the winter months. Simply keep the water balanced, and reduce the equipment time clock to run about half the time that it would during normal swim season.

It is still a good idea to do all of the cleaning steps and the pool can be covered. However, an automatic pool cleaner will continue to keep the pool spotless in the winter provided it is used frequently-making the cover optional.

For those areas where the mercury dips below freezing only a few times a year, run the filter pump continuously to avoid damage from freezing. Some modern automation devices have a temperature sensor that turns the filter pump on automatically to avoid damage from freezing.

Consult your local pool water professional or maintenance specialist for specific recommendations regarding winterizing your pool.