Overflow rates (fluidics help please)

[peterac]

I have two 1.5" overflows on a Tenecor tank that feed down into my sump. The sump is not located directly under the tank, but in a room right behind the tank (about 2.5 feet away horizontally). I was told by someone at Tenecor that the 8X per hour rating that these overflows are rated at are based on the sump being directly under the overflows.

My question: How much slower will the overflows run since the overflows run not just down but horizontally as well???? I am hoping it is negligible.

Thanks,
Pete R.

 

[aquafreak]

I'm not qualified to answer your question quite but my sump is set up the same as yours with only 1 overflow....i figure that my flow rate has been decreased possibly 150 to 200 GPH. I hardly notice the change but I almost wish Id've went with a more powerful pump as an alternative to less powerful set-up.

 

[darb2]

(about 2.5 feet away horizontally)
as long as you don't have any horizontal sections of overflow to sump drain pipe the measurements will be negligible.(At least in these terms)
The only thing that sholuld really choke the flow of an overflow is piping size(try to minimize fittings) , The length of the drain pipe(the longer the pipe is the slower water will flow[this will also be negligible unless you are trying to drain the water to the other side of the house]), and the route the drain takes. (eliminate horizontal sectionsif you can)

how long are the horizontal sections?

 

[peterac]

(about 2.5 feet away horizontally)

how long are the horizontal sections?

Actually my horizontal runs about 4 feet on one of the overflows and about 2 feet on the other. I did a quick calculation by shutting off my returns pumps and calculating how fast the sump filled up. I am estimating only 2,040 gallons per hour which is only 4.5 turns per hour, much lower than the specs of 8 turns per hour. I may need to drill bigger returns (maybe go to 2") in order to get the turnover rate up where I want it.

Thanks,
Pete R.