The main drain is the primary way that water is drawn from your pool into the pump and filter. The main drain is located on the bottom of the pool in the deepest part. Most pools have one, but larger pools may have multiple main drains. Main drains must be protected by an approved cover.
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.
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.
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.
An inground swimming pool's main drain is located in the deep end of the pool. A main drain circulates the pool's water by pulling water off the bottom of the pool and sending it to the filter.
Swimming pool builders often install overflow drains near the rim of the pool that prevent flooding most of the time. If you don't have an overflow drain, or if it is clogged, it is possible for periods of unusually heavy rain to overflow your pool.
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.
Drains and Skimmer
Most pools have one, but larger pools may have multiple main drains. Main drains must be protected by an approved cover. Water is also pulled into the pump through one or more skimmers, located on the waterline. Because they are on the surface, they use baskets to catch floating debris like leaves.
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.
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.
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.
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.
Unscrew the drain cover and place the pool plunger over the drain. Push down on the plunger, then lift up. Repeat this several times to force the clog up and out of the drain.
Turn on the water supply to the hose where the drain king is attacked and allow it to run for a couple of minutes. Stand back and watch the debris get blown back into the pool. Once the water runs clear, you can shut off the water to the hose and your clog should be all gone. Reattach the main drain cover.
Pool drain accidents refer to drain entrapment. Drain entrapment occurs when a drain's powerful suction traps a child's hair, bathing suit or body parts. Drain entrapment can cause serious and fatal injuries, including broken bones, lacerations, internal organ damage, drowning and brain damage.
A single suction line is a high risk system.
No pool should ever be run on bottom drain alone due to the danger of suction entrapment and/or possible hair entanglement on the bottom or side of the pool/spa tank.
Poor water quality, due to an overabundance of Total Dissolved Solids or high levels of Cyanuric Acid, is the most common reason for needing to drain a pool. Even with proper and regular pool maintenance, it's often necessary to drain your pool — completely or partially — every 3-5 years.
A pool's so-called main drain is not actually a drain; that is, it is not used to drain the pool. Instead, it is an outlet, housing a pipe that runs to the pump, which sucks water through a skimmer, then through a filter, then through a heater (if you have one), and then back to the pool via multiple inlets.
So, if you see that you pressure quickly drops to 2 psi, it's likely that there's a leak in the main drain line somewhere between 4′ – 5′ under the water level of the pool. If there is a leak in the section of the line at or above the water level of the pool, you'll see a quick drop to 0 psi.
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.
Although it's generally recommended that all the pool water undergo filtration every 24 hours, the pump does not need to run all the time. A proactive, productive and energy-saving maintenance activity is to remove the debris floating on the pool surface with a hand-held skimmer.
When rain makes your pool overflow, the amount of chemicals you put into the pool are off. Why? There's simply too much water for the amount of chemicals you added to your pool. Rain is also acidic which affects your pool chemistry.
The pool will only overflow by the amount of rain in excess of the amount of rain needed to fill the pool to the top. So if your pool is the normal 3” below the top, the rain would need to exceed 3” before any additional rain would be available to overflow onto the deck.
Put your hand over the inlet (where the basket is located on the side of the pool, not the pump) to feel if there's enough suction. Your hand should be sucked up against the inlet fairly quickly if the pump is set to its highest mode. If it's barely pulling, you likely have a clogged filter or a leak in the line.