HOW POOLS LOSE HEAT

Pools lose energy in a variety of ways, but evaporation is by far the largest source of energy loss for swimming pools.

The reason evaporation has such an impact is that evaporating water requires tremendous amounts of energy. It only takes 1 Btu to raise 1 pound of water 1 degree, but each pound of 80 water that evaporates takes a whopping 1048 Btu's of heat out of the pool.

WHY POOL COVERS

Since evaporation is the major source of heat loss for all swimming pools, to minimize evaporation one must cover the pool. Covering the pool with a pool cover when it is not in use is the single most effective means of reducing pool heating costs. Savings of 50-70% are possible.

ENERGY LOSS

The diagram below illustrates the impact of evaporation on the total energy consumption of the outdoor pool.

The evaporation rate from an outdoor pool varies depending on the temperature of the pool, the temperature and humidity of the air, and the wind speed at the pool surface. The higher the pool temperature and wind speed and the lower the humidity, the greater the evaporation rate.
 

TYPES OF POOL COVERS

Technically, all you really need is a large sheet of plastic. Plastic meets the requirement of being a vapor barrier. But a large sheet of plastic that you get from the lumber store is probably not your best choice. It will be very difficult to handle and store, doesn't help heat your pool, it tears easily, and sunlight will deteriorate it rapidly. You can use it, but it will be very inconvenient and will only last 1 to 2 seasons max.

There are a number of manufacturers that produce covers designed specifically for swimming pools. They can be made of different materials, such as UV stabilized polyethylene, polypropylene, or vinyl. They can be transparent or opaque. They can be light colored or dark colored.

One of the lowest cost covers made specifically for swimming pools is the bubble cover (some call them solar covers).
They are similar to bubble packing material except that they use a thicker grade of plastic and have UV inhibitors, etc.

Vinyl covers are a heavier material and have a longer life expectancy. You can also get insulated vinyl covers with a thin layer of flexible insulation sandwiched between two layers of vinyl.

Outdoor pools gain heat from the sun, absorbing 75-85% of the solar energy striking the pool surface. This is an important contribution to the pool heating needs.

So when considering a pool cover, note that a pool cover will also decrease the solar gain contribution to the pool to some extent, depending on the type of pool cover used. A transparent bubble cover may reduce pool solar energy absorption by 5-15%, and a completely opaque cover by 20-40%.

METHODS OF USE

There are several ways of covering your pool. The simplest and lowest first cost method is to manually pull the cover on and off, fold it, and place it somewhere out of the way. If you are paying someone to do this, you need to consider that cost in your economic evaluation. You can also purchase a pool cover reel that can be used to manually roll the pool cover up. The reel, usually on wheels, can then be rolled out of the way.

Semi-automatic covers use a motor driven reel system. They use electrical power to roll and unroll the cover, but usually require someone to pull on the cover when unrolling, or guide the cover onto the reel when rolling the cover up. They can be built into the pool deck surrounding the pool, or can use reels on carts.

Automatic covers have permanently mounted reels that automatically cover and uncover the pool at the push of a button. They are also the most expensive first cost option. But you have to weigh the cost of labor for the manual and semi-automatic covers to determine which route is best for your particular situation.

Some pool covers are fitted into tracks along the sides of the pool. This prevents anything or anybody from getting into the pool. They even support the weight of several people. If liability is a concern, these are a good option to explore. They can be run manually, semi-automatically, or automatically.

WHEN TO USE A POOL COVER

For pools which are open all day, a cover should be placed over the pool as soon as it closes, and taken off just before it opens for the day.

For pools which are not in use during daylight hours, the effectiveness of a pool cover will depend on whether the evaporation and other losses prevented by the cover exceed the solar gain reduction caused by the cover. This balance is affected by the type of cover and the climate. In dry and/or windy conditions the evaporation rate of the pool increases, and it is generally beneficial to have a transparent or bubble cover on during daylight hours. In warm, humid conditions the evaporation rate decreases, and it may be more beneficial to leave the cover off during the daytime.

OTHER BENEFITS

Pool covers also provide many other benefits beside the tremendous energy savings. They conserve water by reducing the amount of make-up water needed by 30-50%. They can reduce chemical consumption by 35-60%. They also cut cleaning time by keeping dirt and other debris out of the pool.

It is highly recommended that the first step to cutting pool energy loss be the evaluation of the economics of using a swimming pool cover.

(To clarify, we are not talking about pool covers that you use to cover the pool in the off season or mesh safety covers. Those do not save energy. We are talking about plastic or vinyl pool covers that you use during the swimming season when the pool is not in use.)

1. Fill pool to mid-skimmer level
2. Begin filtering pool water. When bubbles from return line cease, immediately add the proper amount of D.E. (diatomaceous earth). The size of your filter will determine the amount of D.E. needed for proper operation. The Sequel I requires 1 ½ lbs. while the sequel II requires 2 ½ lbs of D.E. Pour D.E. slowly into the thru-wall skimmer. D.E weighs ½as much as coffee.
3. “Shock” the pool AFTER SUNDOWN using 1 gal. of liquid chlorine per each 5,000 gal. of pool water. “Shock” is liquid chlorine, the least expensive way to establish an acceptable chlorine level. It is an excellent disinfectant and effective in “bleaching out” water. Pour the required amount of “shock” (see attached chart) directly into the pool water, pouring slowly (be careful not to splash on clothing) around the perimeter of the pool while filter is running. Continue to circulate water at least two hours.
4. Using the test kit provided, test the pH of the pool water. If the test shows very pink (7.8& above) lower the pH using approximately ½ cup LO ‘N SLO (pH minus). If the water tests low (7.1 & below) the test will be very pale pink, clear or yellowish. Adjust this by adding approximatel ½ cup BALANCE PAK 200 (pH plus).It is suggested that you adjust pH with several small doses until you become accustomed to your pools needs. These chemicals may be broadcast over the water surface in its dry form. If the pH reads between 7.2 and 7.6, the water is in balance and no adjustment is necessary.
5. AFTER pool is clear, AND IF the filter has good pressure, (backwash if water pressure back to pool is diminished), turn on pump and slowly add 1 lb. STABILIZER 100 directly into the thru-wall skimmer. Continue to run your filter for 24 hrs. and DO NOT backwash for at least 4 days. This chemical protects the chlorine from the sun and stabilizes the chlorine level. Be sure to check your cyanuric acid (stabilizer) levels each year.

BIO-GUARD ONCE-WEEK 3-STEP PROGRAM

Let’s face it, you got a pool to use it, not CLEAN it. Nevertheless, you have to clean it sometime. Thanks to our 3-Step Pool Care Program, that’s only once a week. From start to finish the program takes just minutes of your time. That’s minutes instead of hours to keep your pool water crystal clear and brilliant.

1. Sanitize with SMART STICKS; Test the Cl (chlorine level). It should remain high for several days to a week after shocking your pool. When the chlorine level drops to approx. 2.0 on your test kit, place proper amount of SMART STICKS (see chart) into your skimmer basket. Top off with 1 or 2 sticks as sticks start to dissolve. Alternative: Chlorine tabs in a floating chlorinator.    
2. Oxidize with SMART SHOCK; Add 1lb. SMART SHOCK for every 12,000 gallons weekly. 
Swimmers can re-enter the pool 15 minutes after treatment.
Alternative: 1 Gallon pool shock for every 15,000 gallons; swimmers can re-enter pool once Chlorine drops to 5ppm (usually 6-10 hrs.)
3. Algae Prevention with BACK UP. Add 1 fl. Oz. BACK UP weekly, for every 5,000 gallons, to prevent algae before it starts. For pools with attached spas, fountains and other water features, ALGAE ALL 60 is recommended.

POOL CARE HINTS

1. SUPER CHLORINATE pool water weekly, especially during the hot weather.
2. Never add more than one chemical at a time to the water allow one chemical to “disappear” before adding the next. Always add chemical to water, never water to chemicals.
3. Skim the pool of leaves, twigs, dust, and bugs periodically to reduce chlorine consumption. Filter an average of 12 hrs. per day, longer or continuously in very hot weather or when water is cloudy.

            Use a SKIMOR (skimmer sock) in your skimmer basket to help keep debris out of your filter.

      4.  WINTERIZE in the fall. Call for instructions before you lower the water!! Ask for Winterizing sheet.

                             START UP CHEMICAL CHART

                                      Gallons         BACK UP oz.         Liquid Shock       Conditioner

BIO-GUARD ONCE-WEEK 3-STEP PROGRAM

                                                           SMART      Chlorine       SMART      Liquid          BACK Up

                                       Gallons         STICKS       Tabs         SHOCK      Shock          Algae