There are two types of pool covers that are most commonly used today. These are the vinyl cover solar the solar cover. Vinyl covers are made from thick plastic sheeting and generally have a long life. They are beneficial in that they prevent evaporation of the pool's water, but they do not add any heat to the pool from the sun's radiant energy. They will help retain the pool's heat, but the insulated vinyl covers will do a better job of heat retention than the single ply vinyl sheet covers.

On the other hand, solar covers both prevent evaporative heat loss and allow the radiant energy of the sun to pass through the cover and heat the pool. Solar covers resemble the bubble wrap that is used in packaging, but are made from a thicker plastic material and have additives to prevent degradation from the ultraviolet light of the sun. Outdoor swimming pools will generally collect 80% of the sun's energy that hits its surface, and a transparent solar cover will allow 90% of this energy through it.

Solar pool covers are estimated to heat the pools water by 10 to 15 degrees F. This will allow the above ground pool heater to use less energy to heat the water and will also bring the water temperature up to the desired level quicker since there is less of a temperature differential to overcome. By employing the use of a swimming pool cover to greatly reduce the pool's evaporative loss, fewer chemicals will need to be added to the pool. Consequently, this will minimize the increase in the pool water's hardness, calcium and total dissolved solids levels and will require less make-up water. This will help prevent scaling in the above ground pool heaters, pumps and filters.

During the swimming season, pool covers should be kept in place while the pool is not being used. When used during the daytime, it is best to remove the cover right before you swim in the pool and replace it as soon as you are done. However, during the warm and humid summer months, it may be more beneficial to leave the cover off since evaporation is minimized anyway. If this is the case, and your pool is located in a windy area, the installation of windbreaks in the form of bushes and shrubs will help further prevent evaporation loss.

Solar pool covers will save money and energy by requiring less heat input from above ground pool heaters, In addition, a solar pool cover will reduce the make-up water required by your pool, lessen the amount of pool chemicals that need to be added to maintain your water balance and reduce your cleaning time since it will help keep dirt and other foreign material out of the pool.

It is a simple question to answer for yourself, providing you remember your elementary school math education and the formulas for calculating volumes. Other than that, all you need to know is that there are 7.48 gallons per cubic foot.

The equation for calculating the area of a circle is 'Pi * r^2/2', where Pi is 3.14 (well, not exactly but that's close enough) and the radius (r) is one half of the pool's diameter. To calculate the volume it is simply a matter of multiplying the area by the depth (or height) to get the pool volume in cubic feet. Lastly, since there are 7.48 gallons per cubic foot, multiply the pool's volume (in cubic feet) by that number to get your volume in gallons.

The table below has the pool volume for some common round and oval above ground pools. Please note that the volume presented in this table, in gallons, assumed that the pool would be filled within 4" of the sidewall height so the water height of a 48" sidewall pool is 44" for the pool volume's calculation.

Pool Volumes by Size

Your pool water is circulated through the heater by the pool pump and gathers the generated heat from the heater in the unit's heat exchanger. A fluid inside of the heat pump is in a closed system that is not exposed to atmosphere. A refrigerant such as Freon or a similar chlorofluoro hydrocarbon is circulated through this loop. This fluid is compressed by the compressor and when this warm gas is compressed it concentrates that heat of the fluid. At this point that heat is transferred from the compressed fluid to the water via a heat exchanger, which is essentially a set of tubes with the hot fluid on the inside and the cool water on the outside. At this point, the two fluids try to reach a temperature equilibrium where the pool water is heated and the heat exchanger's fluid is cooled. Upon exiting the heat exchanger, the refrigerated passes through an expansion valve and returns to the low pressure side of the system. While this fluid is under low pressure, it passes through the evaporator coils and cooling fans of the system to remove the cold air via a fan. At this point the refrigerant again starts to cycle through the system and gain heat through the compression process.

Heat pump pool heaters use either scroll compressors or reciprocal compressors. The scroll compressors are more efficient in their operation and are found in higher efficiency heat pumps.

Heat pump pool heaters use more energy in their operation when the ambient temperature is lower. However, when the outside air temperature is 50° or higher they will be able to operate in an efficient manner. This is generally not a consideration for most pool owners since they only utilize their swimming pools during the warmer weather.

Although heat pump pool heaters for above ground swimming pools have a higher initial cost than gas pool heaters, their operating costs are much lower due to their increased efficiency. Generally, they will produce five dollars worth of heat for each dollar of electricity used. Additionally, heat pump pool heaters generally last 10 years or more and have a usable lifetime that is about two times greater than the life of the average gas fired pool heating unit.

The water needs to circulate in order to move it through the required treatment processes. The swimming pool pump is used to do this. In your house, the water flows through the pipes because the pressure or motive force is supplied by the water company by a pump or the pressure created by a storage tank if you are supplied by a water utility company and by a pump if you are serviced by well water. The pool pump serves the same purpose. It provides a suction on its intake side to draw the water into it and discharges with a positive pressure to force the water through the trailing components and reture the treated water to the swimming pool.

After the water is discharged through the pump, it passes through a filter to remove and particulate matter that has settled into the poll. Swimming pool filters generally use sand as the filtering media, although cartridge and grid type filters are also commonly employed. Filters operate by a mechanical action and do not alter the water chemistry, but simply remove the solid impurities.

Many owner opt to install a pool heater to expand their swimming pool season, and this component is generally next in line. Above ground pool heaters are generally use gas, either natural gas or LP gas, as their heat source. However, swimming pool heat pumps are gaining popularity due to their lower operating costs. Electric resistance heaters are not as common as they once were due to the increased cost of electricity. Although solar panel pool heaters offer lower operating costs due to the fact that they don't need an energy source other than the sun to heat the water, they are not as popular with above ground swimming pool owners due to their high capital costs and the space requirements of the panels themselves.

Once the water has exited the heater, it is next passed through the chlorinator for disinfection purposes. Although some form of chlorine can be manually added, an electronic chlorinator automates the process and eliminates the need to constantly monitor the water chemistry and deal with harsh chemicals. Electronic chlorinators also use common salt that is converted to chlorine by the unit to save on operating costs.  This chlorination step is critical for the proper destruction of bacteria and virused whether you choose to automate the process with a chlorinator or add the chlorine via a manual process.

Although the absolute minimum requrements to maintain your pool can be achived with only a pump and a filter, the addition of an above ground swimming pool heater and an electronic chlorinator will extend and better maintain a healthy and happy pool environment.