If the pool is kept in pristine condition throughout the year, you should never have to drain it. If you do want to drain it, drain it every ten years or so. (You run a risk of damaging your pool by draining it.)
A: Not all the above answer is exactly correct. Through evaporation and refilling the pool you accumulate minerals that cannot be filtered out. Another factor is that of your water make up or fill water. If it is hard water that may didctate just how often you pool is drained. SO, on the average, lets say, in California, you may drain your pool about every 8 to ten years. A clue on when to drain is - when you start to have a very difficult time trying to balance the chemistry including the chlorine then it is time to think about draining and refilling the pool.
The only risk is if you drain or try to drain a pool after prolong rains or is you are aware of how high the "water table" is in your area. In order to get that info you may have to call your water district and ask them. "high water tables" make draining a pool a dicy situation. The result of an empty pool during these conditions is usually a pool that will float out of the ground. It will act like a bath tub or a boat ...even if it is made out of steal reinforced cement.
Improved answer: The 2nd answer up there is actually more correct that the first. You do definitely need to drain your pool at some point. We in the pool industry recommend every 5-7 years. That's only because in that amount of time the water does get too complex and the chemicals stop working. The chemicals will register that they are present but they ARE NOT WORKING. I tell my customers to think of it this way, think of all the chemicals added to the pool over the years, add on all the people scum, urine, pets, dead animals all the dirty things that can end up in your pool. Do you want to swim in that after more than 7 years? No that's gross, and your water will be gross, it needs to be drained every 5-7 years. It doesn't harm your pool to drain it. To leave it drained yes then your pool will be ruined. Remember to watch the water table or amount of moisture in the ground because the chance of a pop out is much greater. If you have questions about these things contact a local pool contractor or company. Not a retail location because their main focus is to sell, not service.
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Vacuum the pool. If you have to drain it, only drain it half way. Floating pools are a disaster.
No, then you have to refill it and that is a waste of water If it is an inground pool being dry will ruin the pool surface and in high water table areas the risk of turning it into a boat is very real.
Once a week really
Hmmm, do you possibly mean the back wash valve on the filter? This valve has many positions to choose from especially for sand filters. Filter, back wash, drain, drain to waste, filter bypass, closed. They are pretty much self explanatory. Normal position would be the "filter" position while the pump is running and the filter is working. Ken
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A drained swimming pool will be more dangerous to anyone who could fall into the pit. The pool will need fencing around it that is sturdy and anti-tamper proof. What are your plans for rain water when it fills during a storm? What are your plans for when you have a lot of rain and the water table surrounding the pool rises enough to make the pool float out of the ground????
The main drain should be split to two drain basins at least three ft. apart. This is done to prevent suction entrapment.
Why would you drain your pool just becasue the water is hot? Never drain your inground pool unless you have first cut holes in the bottom of the pool to keep it from floating. If the water table in your area is high enough, your inground pool could "float" out of the ground, effectively ruining your pool.
NO however you should keep in mind that the ground water outside of the pool is not going to put pressure on it as this is capable of even lifting a concrete pool out of the ground.
If the car is on (Ignition is on, engine is running) then no. Nothing should drain the battery when the car is running, there is a device called an alternator with a belt that usually goes around the crankshaft that transforms the mechanical energy into electrical energy. As long as you have the car running, the battery should not die. If so, you have a mechanical problem.
I would think not. If it is an inground pool and the "drain" is at the bottom of the pool this should also be running through the filter. It should be filtering from the skimmer basket and the bottom drain. At least that is what I have seen. while I agree it is not the proper way and "maindrains" are great for circulation, also know that many pools work fine without them and a quick fix of plugging the drain typically cost anywhere up to 250.00 while removing the deck, findin gand repairing the problem correctly can cost upwards of 10,000.00 so it should be left up to the customer if its not a warranty job. if it is the builder should bite the bullet and fix it right (i hate to say that because i am a builder but its the right thing to do)