Skimmer / Jet Arrangement & Patio Drainage

[Rags]

Just finalising the details for my 8.3m x 4m x 1.4m salt water skimmer type pool with concrete steps to one side and I'd appreciate your thoughts on two areas.

 

1) Best positions for the skimmer and return jets.  I plan on having a floor drain and two skimmer boxes with the return jets angled to create clockwise water flow.  Concerned about water movement around the steps so was thinking about placing one there plus one further up the pool as well as maybe adding one on the left hand side - any thoughts  on the best arrangement?  Any benefit to also adding a couple at the bottom of the wall as well?

 

2) Patio drainage ideas around the pool.  The brown areas in the picture show the extent of the existing patio tiling.  My current thinking is to place a slot drain along the full length (shown in red) and then to have a slight slope in the new pool patio (shown yellow) from the pool down to this point.  

 

Cheers 

 

Rags

 

[grollies]

Skimmers should be positioned downstream from prevailing wind. If sheltered then wherever you like. I'd put the skimmers one each side at one end.

 

Return jets: from memory the size of the eyeball opening is 17mm. If you plan using a 2" pump you need to supply sufficient return jets to allow the pump to operate at maximum capacity whilst sizing for a slight back-pressure against the pump. So for 2" pipe pump discharge you'll need 8-9 return jets (surface area calcs).

 

Pool drain there should be two, spaced 2m apart to prevent anyone (kids usually) getting pulled onto the drain.

[Bagwain]

Typically that size pool 4 returns. Maybe one more for the steps in your drawing to avoid a dead spot!

50,000 is not a large pool and would get away with 1 or 1.5 hp pump married to the right sized filter.

Make sure you get 50 mm plumbing!! 

 

Yes - end opposite prevailing winds for (One) skimmer that is the right size!

Kids don't get sucked into main drains on domestic pools!! ????

They have enough trouble sucking the dirt in!!! ????

Edited January 26, 2019 by Bagwain

[Rags]

Thanks guys, much appreciated.

 

Revised thinking shown in the attached sketch.  I was hoping that the two drains and the second skimmer would improve the water circulation and help with keeping the pool clean, even though the water volume suggests one skimmer should suffice - is this approach actually worthwhile?

 

I have shown the proposed jets and their direction on the sketch - any comments on these?  Presumably these jets would be near the surface, but is there any benefit in adding some more jets at the bottom of the wall to improve circulation throughout the entire depth of the pool and not just on the surface?

 

Cheers 

 

Rags

 

[grollies]

21 hours ago, Bagwain said:

Kids don't get sucked into main drains on domestic pools!! ????

They have enough trouble sucking the dirt in!!! ????

Presumably the OP's system will be set up to pull around 75% on the skimmers and around 25% on bottom drains which means there will be the potential to close the skimmer valves and pull through the bottom drains only.

 

Accidents usually occur as a result of a series of cumulative circumstances, on their own not a problem but when the right set of conditions follow on from one another....

 

Risk assessment is all about eliminating risk, adding a second drain costs peanuts compared to the (yes, very remote) risk of forgetting to open the skimmer valves and pulling your six-year old onto a drain and drowning. But that's just me.

 

To say kids don't get pulled onto drains in domestic pools is irresponsible. Loose the stupid emojis or are you twelve?

[Bagwain]

One skimmer enough.

2 you double the chance of the system running out of water when low.

Pumps need the feed. Pumps don't like running with out the water flow unless you have a decent salt chlorinator that will shut it down when no flow is detected!! 

One main drain is enough and at 25 % (Very unlikely at 100%) wouldn't pull the skin of a rice custard let alone drag a child in.

Complete B/S about pulling a child in!! I call it what it is.

Go into a domestic pool and stick your foot over the main drain & try with 100%. 

(make sure you wear a floatie so you don't get sucked in) ????????????????????

Commercial pools are a complete & total different issue & it has been know to happen becuase of mainly stupid design!!

The skimmer with the lid off is the way more dangerous!!! ????????

But obviously more experienced people here than me!! Ho Hum!! 

 

 

Edited January 27, 2019 by Bagwain

[grollies]

31 minutes ago, Bagwain said:

One skimmer enough.

2 you double the chance of the system running out of water when low.

Pumps need the feed. Pumps don't like running with out the water flow unless you have a decent salt chlorinator that will shut it down when no flow is detected!! 

One main drain is enough and at 25 % (Very unlikely at 100%) wouldn't pull the skin of a rice custard let alone drag a child in.

Complete B/S about pulling a child in!! I call it what it is.

Go into a domestic pool and stick your foot over the main drain & try with 100%. 

(make sure you wear a floatie so you don't get sucked in) ????????????????????

Commercial pools are a complete & total different issue & it has been know to happen becuase of mainly stupid design!!

The skimmer with the lid off is the way more dangerous!!! ????????

But obviously more experienced people here than me!! Ho Hum!! 

 

 

To quote a few stats:

 

What is a Circulation Entrapment Injury?

Circulation entrapment is a fancy term for when a swimmer is trapped by suction generated by water rushing out of the drain of a pool, hot tub or spa. These injuries happen when a swimmer gets hair, jewelry, accessories or even a limb stuck.

Sadly, circulation entrapment is most common among young swimmers, who generally lack the physical strength to free themselves from the suction, leading to injuries and sometimes even death.

According to statistics:

• Between 2009 and 2013 there were 33 instances of circulation entrapment.
• Swimmers suffered injuries in 85 percent (or 28 people) of those instances of circulation entrapment.
• Of those victims, 21 were children who were 15 or younger.
• 45 percent of the reported circulation entrapment injuries happened in a pool.
• 33 percent happened in a spa.
• 21 percent happened in a whirlpool tub.
• Overall, 64 percent of the circulation entrapments occurred in public places

Source:

https://www.edgarsnyder.com/statistics/swimming-pool-statistics.html

 

Just one example and Google is your friend. I'll leave it to the OP to make his own mind up.

 

You profess to be a pool expert but really you are a joke.

[Bagwain]

11 hours ago, grollies said:

To quote a few stats:

 

What is a Circulation Entrapment Injury?

Circulation entrapment is a fancy term for when a swimmer is trapped by suction generated by water rushing out of the drain of a pool, hot tub or spa. These injuries happen when a swimmer gets hair, jewelry, accessories or even a limb stuck.

Sadly, circulation entrapment is most common among young swimmers, who generally lack the physical strength to free themselves from the suction, leading to injuries and sometimes even death.

According to statistics:

• Between 2009 and 2013 there were 33 instances of circulation entrapment.
• Swimmers suffered injuries in 85 percent (or 28 people) of those instances of circulation entrapment.
• Of those victims, 21 were children who were 15 or younger.
• 45 percent of the reported circulation entrapment injuries happened in a pool.
• 33 percent happened in a spa.
• 21 percent happened in a whirlpool tub.
• Overall, 64 percent of the circulation entrapments occurred in public places

Source:

https://www.edgarsnyder.com/statistics/swimming-pool-statistics.html

 

Just one example and Google is your friend. I'll leave it to the OP to make his own mind up.

 

You profess to be a pool expert but really you are a joke.

Name calling now.

Who is the joke.

You can make what you want out of THOSE CDC figures.

Majority happened either in a spa (Which can be dangerous) or a public place (Commercial pool) where both have more powerfull suction.

 

If a small child just happened to be "Entrapped" at the deep end of a small domestic pool then a question is why is a small child was allowed in the deep end & without supervision? If it was not deep then a smaller pump would be in use, which in turn makes it highly unlikely again!

Then other issues come into play. Childproof fences & supervision for example!

Again it is the skimmer lid missing that most entrapment's happen in the domestic arena!

 

Just use common sense when getting your pool built and don't get carried away with fear mongering.

[Bagwain]

19 hours ago, Rags said:

Thanks guys, much appreciated.

 

Revised thinking shown in the attached sketch.  I was hoping that the two drains and the second skimmer would improve the water circulation and help with keeping the pool clean, even though the water volume suggests one skimmer should suffice - is this approach actually worthwhile?

 

I have shown the proposed jets and their direction on the sketch - any comments on these?  Presumably these jets would be near the surface, but is there any benefit in adding some more jets at the bottom of the wall to improve circulation throughout the entire depth of the pool and not just on the surface?

 

Cheers 

 

Rags

 

I would have 3 or 4 jets at the right end. 2 eyeballs facing down & 2 along the surface towards the skimmer.

1 on the opposite side in the stairs facing towards the skimmer.

1 x main drain & skimmer size to suit.

(This would be proper hydraulics for that shape & size).

Pump room is in a good position.

You need to take into consideration the length to the inlet/returns for the size of pump. This depends on the make & the "max head" (Distance from pump to jets) Turnover time should be between 4 to 6 hrs. This can be calculated by the litres p/m for the pump. Make sure the filter matches the rate of the pump. Native builders tend to have either or to big or small! 

(Use 2" 13.5 size PVC plumbing. Not 1.5" & 8.5 PVC)

 

   

[grollies]

5 hours ago, Bagwain said:

Name calling now.

Who is the joke.

Ok, apologies for the name-calling but you exasperate me.

5 hours ago, Bagwain said:

You can make what you want out of THOSE CDC figures.

Majority happened either in a spa (Which can be dangerous) or a public place (Commercial pool) where both have more powerfull suction.

So, by default you admit domestic pool entrapment does happen, just not the majority.

5 hours ago, Bagwain said:

 

If a small child just happened to be "Entrapped" at the deep end of a small domestic pool then a question is why is a small child was allowed in the deep end & without supervision?

You're kidding right? And who said anything about a deep end? From what I read on this forum most go for pools with no slope. The OP says 1.4m.

5 hours ago, Bagwain said:

 

If it was not deep then a smaller pump would be in use, which in turn makes it highly unlikely again!

Wrong, a 1" pump will produce the same suction force, albeit on a smaller diamter drain. Still get hair pulled into it and held down underwater.

5 hours ago, Bagwain said:

Then other issues come into play. Childproof fences & supervision for example!

Again it is the skimmer lid missing that most entrapment's happen in the domestic arena!

Not if you have more than one skimmer, and if your pulling on skimmer and main drain......

5 hours ago, Bagwain said:

 

Just use common sense when getting your pool built and don't get carried away with fear mongering.

Come on Baggers, it's not fear mongering, just plain old common sense, eliminate the risk....like putting up a child-proof fence?

[Valentine]

For my 2 bib's worth I would have skimmer in the corner nearest the pump room, floor drain at the other end, 4 eyeball inlets equally spaced out on the side opposite the steps. Eyeballs tend to fan out in all directions & pool is only 4m wide so water will fan out to the other side then get pulled back to the corner & a little towards the main drain which can be left partially open to help get water to the pump if the level drops below the skimmer.

[grollies]

5 minutes ago, Valentine said:

For my 2 bib's worth I would have skimmer in the corner nearest the pump room, floor drain at the other end, 4 eyeball inlets equally spaced out on the side opposite the steps. Eyeballs tend to fan out in all directions & pool is only 4m wide so water will fan out to the other side then get pulled back to the corner & a little towards the main drain which can be left partially open to help get water to the pump if the level drops below the skimmer.

Normally your pump should be sucking 75% on the skimmers, 25% on main drains. If the water level drops below the skimmers you'll just end up pulling air through the pump.

[Bagwain]

2 hours ago, grollies said:

Normally your pump should be sucking 75% on the skimmers, 25% on main drains. If the water level drops below the skimmers you'll just end up pulling air through the pump.

Yea if plumbed correctly!

However being from the "Land of the great unwashed" & owning a pool makes you the keyboard expert!!

I stand by my statements & they are not from your friend Mr Google!!.

Although he is good as is bad. Makes to many keyboard warriors experts. (Spurts)

 

Some Emojis for ya!! 

????????????

 

 

 

 

[grollies]

11 hours ago, Bagwain said:

Yea if plumbed correctly!

However being from the "Land of the great unwashed" & owning a pool makes you the keyboard expert!!

I stand by my statements & they are not from your friend Mr Google!!.

Although he is good as is bad. Makes to many keyboard warriors experts. (Spurts)

 

Some Emojis for ya!! 

????????????

 

 

 

 

thanks, whatever mate.