Most pools have two main drains, but a small pool may have only one. The drains are positioned at the pool's deepest point.
When constructing a new swimming pool, if you are going to use a main drain it is required that you use two. This is due to safety regulations to help prevent Main Trap Entrapment. Main drain entrapment occurs when the suction is so great through a single main drain that a person can become stuck on or in the drain.
The two drains must be located between 3 feet and 6 feet apart measured from the centerline of the drain covers. The main drain piping must be manifolded at the hydraulic center.
The use of two main drains allows the water flow to be diverted equally between two intake ports and suctioned through a new domed, slotted anti-vortex cover. In many cases the drains are also spaced several feet apart, lessening the intake flow.
Main drains are not required in an inground swimming pool, however, they are strongly recommended and can be extremely useful in some circumstances. The advantages of main drains are to give you the ability to drain the water from your pool without the use of a sump pump. This is useful when replacing your pool liner.
Many pools do not have them. They are not required. They might add slightly improved circulation and can be helpful for removing debris, but there are ways to counter these without the floor drain.
The main drain for a pool is a suction port that should be located at the deepest point on the pool floor. A main drain is responsible for aiding in the circulation and filtration of the pool water. Having a properly working and dedicated main drain line can also allow you to fully drain your pool if necessary.
you can tell if your main drain is working by perhaps putting a leaf on it. If it sticks, its working. In any case though, the main drain is not why your pool is having a problem. It has nothing to do with your pool turning green.
Main Drain: The main drain is typically located at the deepest point of the pool and is used to lower the water level, however its primary purpose is to circulate water from the bottom of the pool. It is recommended that about 1/3rd of the circulated water come from the main drain.
For proper water circulation, it is best to position the flap so that it is about 2/3 closed. This will allow for more flow through the main drain than through the skimmer, which will promote a "bottom-to-top" circulation throughout the pool.
Square drains are the most popular in terms of shape and drains that measure between two and four inches are our most popular sizes.
Locate the small hole at the bottom of the main drain. This is the plumbing line to the filter. Plug the small hole with an expandable rubber plug or a plastic threaded plug, if the hole is threaded. Replace the main drain lid if needed.
Most pools have two main drains, but a small pool may have only one. The drains are positioned at the pool's deepest point.
During normal operation, water flows to the filtering system through two or more main drains at the bottom of the pool and multiple skimmer drains around the top of the pool. The main drains are usually located on the lowest point in the pool, so the entire pool surface slants toward them.
According to the Consumer Product Safety Commission, the pressure on some pool drains can be as strong as 300 pounds per square inch. 1 This kind of pressure can suck in hair or body parts, or trap swimmers underwater and cause them to drown, even if someone is trying to pull a victim away from the drain.
Or, as was the case in this wading pool incident, an open drain can suction organs out of the body. In 1993, Valerie Lakey, 5, was playing in a wading pool at a recreation club in North Carolina when she became caught in the uncovered drain's vortex. The pull was so strong that she was disemboweled.
Skimmer Vs. Drain. If the pool receives a lot of leaves and other debris, more suction may be required at the skimmer than the main drain to adequately strain debris floating on the surface. Conversely, if dirt on the bottom of the pool is the principal contaminant, more suction is required at the main drain.
While many professionals install two returns, some prefer more as a general rule. Builder Guy Wood, for instance, often will place four returns in pools that measure 250 to 600 square feet. A vessel of 600 to 800 square feet will generally have six returns to start.
A pool's main drain can become clogged with debris. Your swimming pool's main drain requires regular maintenance. Although the rest of the pool's parts, such as the filter, may seem to be working just fine, the drain is always at risk of getting clogged.
To find out which specific pipe is blocked, run your pool pump and check each line by itself by shutting off the other lines (skimmer lines, main drain line) and looking at your filter's pressure gauge. If a specific line has lower pressure than the other lines, then you've found your blockage.
Pools will need to be drained and refilled every 5-7 years on average, or if there is a major necessary repair. Otherwise, avoid draining your pool if at all possible. Basically, if you want to know when to drain a swimming pool, the answer is when you have no other alternative.
Turn the filter off (or unplug it) and set it to Waste. Shut off your skimmer and open your pool's main drain. Turn your filter on and the water will start to pump through your backwash hose. Allow the water to drain.
The standard 1.5″ wide deck drains, which inevitably get clogged and break, are at the bottom of the spectrum. From there, systems are available in all cost ranges, up to 10 times the cost of the low end product. I should point out that quality systems are available at affordable prices for those watching the budget.