How Bad is a 28.8K gal 12 hr Turnover Rate for 55K gal pool

[tvretired]

While trying to correct some chemical problems in my pool I decided to replace the sand in my filter, only to realize that the 300 lbs of sand needed was the same amount I had in an earlier 25 K pool. Turns out the pump/filter were not part of my chemical problem, but I was concerned nevertheless.

I went to the Hayward website and used their 3 page worksheet to determine the correct size pump and filter. Bottom line is I calculate my 12 hr turnover rate at 28.8K gal and I have a 55K gal pool. I run it 24/7 from season start to finish, so I get a full turnover every 24 hours and do not have to backwash more then every week or more. Pressure goes from 16 psi to 22 psi before I backwash since letting it go over 22 psi really drops the flow.

I contemplated going to a full rated 1.5 HP Hayward High Efficiency Superpump and would need a Hayward 700 lb S360 filter to handle the flow. My pool has only 1 1/2 piping with 2 skimmers and 1 main drain each on a separate line, so the total head from the suction line runs is high. My shortest suction side run is 5-6 feet and the other 2 I estimate at 65' and 85' feet, so I am not pleased with the builder! Is 2" piping too much to ask for crying out loud. 4 return jets, teed 2 to a return line.

The builder says his pool is the same size as mine and he has the same equipment I do. He strongly recommends running 24/7 for circulation and lowest chemical useage. Since the filter does not need backwashing any more frequently then my old 25K gal pool it does not seem to me that the filter is plugging up with crud too often.

Pool was built in 2006. How important is a 8 vs 10 vs 12 hr turnover rate anyway? Any suggestions on what I ought to do?

 

[Hotrod30]

I'm no expert, but the 24 inch filter seems kind of small for your size pool. I changed to a S270T2 (2 inch inlet and outlet) filter for my pool last year and happy I did. All my lines are one and a half inch until they come into the pump house. I use 1.5/2 inch valves to increase the pipe size to the pump; 2 inch to the filter then a 2 inch to 1.5 inch Y reducer to the two return lines. Also, the Pentair VF pump (2 inch inlet and outlet) works great.
I'm very happy with that set-up. I changed piping, filter and pump at one time.

If you are thinking about getting a new pump, look at the Pentair VF for your pool. The only trouble with that is your filter is 1.5 inch; which I also would change.

Do you have room for a larger filter?

 

[tvretired]

yes, I can enlarge the pad to move my heater off to the side more, eliminate the Nature 2 and slide the Polaris pump over and a larger filter will fit. I looked at the info in a table somewhere on this site and see that (3) 1.5 " suction lines all open at once gives a capacity of a 2.63" or so single suction line.

If I increase the suction line to the pump to 2 " (up from 1.5 ") from the 3 to 1 manifold that brings all (3) 1.5 " suction lines into one and then pipe 2" all the way from there thru the filter to heater and then split it off to the (2) 1.5" pressure lines feeding the 4 return jets it seems that I can increase my flow to handle the larger pump and filter. I can give the exact numbers from the Hayward worksheet if I can find the darn thing in the mess at my desk.

If that is true, then my turnover rate will be down in the 8-10 hr range I would like to see.

My question is: is it worth all the work and expense? My concern is if my filter goes 1 week without need for backwash, how important is the turnover rate? It does not seem that I am filtering so much crud out of the pool that I need the larger filter area. How important is it to circulate the water that fast if I am not using an in-line chlorinator? Exactly what benefit does this give me given the cost of the project?

Knowing what I do now, I wouldn't have accepted the builders proposal with the current setup. Larger piping is a no brainer and I would have gladly paid the extra few hundred dollars for the better pump and filter. Actually, eliminating the Rainbow chlorinater and the Nature 2 would have more than offset the other increased costs.

As my younger sister once told me when I burned my hands on vacation last year: "isn't it nice to know one is never too old to learn something new"

 

[duraleigh]

My concern is if my filter goes 1 week without need for backwash, how important is the turnover rate?

That a good point TV.

I certainly agree with Hotrod that your filter is w-a-a-y to small for that pool. (my pool is 42k with a 925lb sand filter) However, if your system is not broke (i.e......you are able to keep your water crystal clear) then I would hesitate to fix it.

If you are having continual water quality issues, a much larger filter would be a pretty good benefit.

 

[Heckpools]

you should NEVER have to run a filter 24/7 unless you have serious issues and are trying to clear up a pool..

i think your builder sounds like the guy i onced worked for... Edited for politeness. JasonLion

 

[JasonLion]

A "properly designed" pool typically has a pump that is capable of between two and three turnovers per day. However, as long as your pump is capable of one turnover a day it should work just fine and it will use less electricity than the "correct" pump would require.

If it works, don't "fix" it.

 

[tvretired]

Can anyone think of any likely circumstances where I will need a higher turnover rate? I have generally thought you can keep your pool clean using a proper filter and a small amount of chemicals or a poor filter and A LOT of chemicals.

IOW, if I am just getting by under normal circumstances with a marginal pump and filter running 24/7 than what things can cause the pool to go south on me that could have been fixed by increasing my pump time if I had the ability to go to a 8-10 hr turnover rate?

 

[Buggsw]

A "properly designed" pool typically has a pump that is capable of between two and three turnovers per day. However, as long as your pump is capable of one turnover a day it should work just fine and it will use less electricity than the "correct" pump would require.

If it works, don't "fix" it.

Believe me, I'm no expert. Don't understand pumps, electricity, volts, watts, amps or anything close, BUT, how can it use less electricity if he has to run it 24 hours to turn his water over just once? If he had a larger pump and could turn the water over at least once in 12 hours and not have to run the pump 24 hours, wouldn't that actually be at least equal to the electricity used with the smaller pump over a 24 hour period? I'm trying to understand.

 

[tgramm]

hmm I like to see pools that can have a full turn over in 6-8 hours.

Your filter is the single most critical componet in your pool sanitation. If your pool has poor circulation yet proper chemical balance, the oxidized biologicals will simply settle in the bottom of the pool and stay until vaccumed. It's best to get them through the filter while they are still susspended in the water.

1.5 inch plumbing is a hard problem, there are not too many pumps on the market today that will provide the circulation you need with out the pump cavitating and operating at a greatly reduced rate. Also, 1.5 plumbing is infamous for getting obstructions in the joints. Make sure your cleaner use's a leaf catch before it enters the pool plumbing.

FYI your filter can never be too big.

Hope this helps.

 

[JasonLion]

If he had a larger pump and could turn the water over at least once in 12 hours and not have to run the pump 24 hours, wouldn't that actually be at least equal to the electricity used with the smaller pump over a 24 hour period? I'm trying to understand.

The amount of energy required to move water mostly depends on how much "friction" there is in the pipes. Higher flow rates cause much more "friction", so they require more electricity. The energy lost in the pipes goes up far more quickly than the amount of water, high flow rates are inefficient. What I am calling "friction" is really called total dynamic head (TDH), a measure of how much energy is lost due to various kinds of resistance to flow.

Typically, a pump that moves half as much water uses around one third as much electricity per unit time. Since you need to run it twice as long, you end up using 2/3rds as much electricity to move the same volume of water. This is why two speed pumps are so nice, you run them on low speed for twice as long and still use less electricity than you would on high speed.