Main Drain Safety
I can’t attest for all builders but the way Crystal Pools and Spas install main drains are very safe. And here are the reasons why and what you should look for as far as saftey. Us at Crystal Pools and Spas Inc. plumb our own pool, so I have an exact idea how our system operates. We run a 2″ plumbing line to each of our 3 pool suctions. There are two skimmers in most pools by us and 2 main drains that are tied into one pipe. On top of that we use anti-vortex main drain covers. Think of these as domed and where the water is sucked on the sides. A traditional main drain cover is flat and sucks right out of the top. So say you have somebody sit on this domed top 100% (which would be very hard to do) the other main drain would do the extra sucking and very little sucking would happen from the first. Like I said that is if the pool is done correctly. If you have a company build a pool and the plaster man gets plaster inside of one of the main drains pipes well the other will do most of the sucking and then the system could be compromised. Ok you may ask how about if two people cover both main drains (it would almost be impossible for one to block both with a pool done by us because we space the two main drains a few feet apart) what will happen. Well with a pool built by us like I said we run a 2″ pipe to each skimmer and a 2″ pipe and T it off to two main drains. So what this means is each skimmer is sucking around 33% of the pool water and each main drain is sucking at say 17% each. So going back to my question if two people block both drains 100% then the skimmers would be sucking from 33% each to closer to 50% each relieving the pressure off of the main drains.
There are contractors that will tell you they will install state of the art equipment to prevent hold down on the main drain but if a swimming pool is constructed correctly you do not need this. Where problems occur are owners that chose the cheapest bidding contractor and then quality and supervision goes downhill. For instance, I bid all the time and know what the other contractor is bidding on and will tell the homeowner and they fall in love with a price that excludes LOTS of variables. A big on is a contractor will do small things like put one main drain in the pool instead of two and the big thing is they will install smaller sized plumbing lines like 1″ so that their bill is less. They will also tie lines in together so for instance even if a contractor you choose installs two skimmers in your pool doesn’t mean that each of those two skimmers have a dedicated line running from them to the pool pump. What a lot of companies choose to do is if they put two skimmers in their pool they will use one pipe sometimes 1″!!! in diameter and tie in the two skimmers into the pool pump. If a system is set up like that they will usually put in a smaller pump and a smaller filter to get the cost WAY down and you are left with an inefficient and unsafe pool. So let’s say you have 2 skimmers and 2 main drains by a contractor and they plumbed this way with say the same size pump as I would do a 1.5 HP or a 2 HP then first the pump is struggling for water because the flow rate of the smaller pipe and one less inlet of the pool(1 line to the two skimmers), but also your main drains are now sucking 50% and your two skimmers are at about 25% each. This could be a larger safety concern and a person needs to remember you get what you pay for.
Remember to, if you have a older spa/hot tub and it has one main drain make sure you have a anti-vortex main drain cover and make sure the cover is installed tightly!!! This main drain will be sucking 100% of the water and can easily hold down even an adult. At Crystal Pools and Spas Inc. we put two main drains and anti-vortex covers on all of our hot tubs and so should EVERY contractor and you should not do otherwise. If you have any questions to how your pool system may work or any safety concerns you may have just email us at kevin@nolapools.com. And if you live in SE Louisiana or southern Mississippi please give us at Crystal Pools and Spas Inc. an opportunity to serve you, you won’t be disappointed! Thanks!!
Main drain safety
