overflow a constant flushing sound

[OttawaReefer]

I'm hoping that someone can give me a hint on shutting up this overflow.  I've attached a picture for people to see.

It's basically a U-shape.....but the constant flushing is driving me up the wall!

[attachment deleted by admin]

[Quatro]

check out http://dursostandpipes.com/

[OttawaReefer]

Thanks.  I was a bit of a dummy and forgot to put an airhole on the top of the elbow outside the tank, right before the pipe to the sump.   Duhhh.   I'll make a hole tomorrow as I have to take the bulkhead apart because it's leaking a bit....a slow drip.  I'm going to put some silicone on the rubber gaskets and then put them back together again.

[Quatro]

Are the elbows completely underwater?  I can't tell from the pic.  Even if they're not the water level could rise and a hole where you are suggesting could be a bad ideal.  I would change the elbow to a T and add some pipe to raise the hole to the top of the tank.  The durso site says that the hole size will effect the noise.  A large hole (ie. open end of pipe) could be just as loud.  Cap the pipe end and drill a small hole.

[OttawaReefer]

both elbows are completely under the waterline of the tank.  The waterline of the sump doesn't go all the way up to the hole.

[Hookup]

How many down (drain) lines do you have from your system?  Just this one, or are there two by chance?  Or could there be two?

[OttawaReefer]

nope, just the one.  I drilled a hole at the top of the elbow outside the tank and it's made the system fairly quiet, but it occassionally spits up some water from that hole.

[Hookup]

What's happening, I think.

The down-line is not capable of handling the volume of water you are sending down as a DURSO or a flooded line.

The Durso operates by water slipping down the outside of the pipe, think of friction holding the down-flowing water to the pipe walls.  This allows for air to flow/exist down the center of the pipe.  For this to work two conditions must exist.  First, the volume of water must be low(ish) and you must allow air into the pipe so that the friction of the water, pulling the air down, can be replaced.  This is the little hole you added, and why.

However, in your case, what I think is happening, is the water flow is still too high, or the air being allowed in is too low which is choking the pipe.

Can you guess how much water is flowing up into your tank in terms of GPH?

Also, how big is your drain line?

And finally, is there any way to add a second drain line?  If there is there are cool things to do...  

[salvini55]

Im not sure if this would work for you or not but consider using a HOB overflow to tag team with your drilled line. IF it fails at least you have the drilled line for safety... Thoughts?

[OttawaReefer]

The pump is listed at about 1000GPH, but has a pipe height of about five feet.....so it should be a fair bit less than that.  The bulkhead and tubing is 1.5" diameter, so it should be capable of even more than the actual 1000, which I'm not getting because of the height. 

To be honest, the flow out of the pump into the tank, and into the overflow, isn't as much as I thought it would have been.

[Hookup]

The pump is listed at about 1000GPH, but has a pipe height of about five feet.....so it should be a fair bit less than that.  The bulkhead and tubing is 1.5" diameter, so it should be capable of even more than the actual 1000, which I'm not getting because of the height. 

To be honest, the flow out of the pump into the tank, and into the overflow, isn't as much as I thought it would have been.

Ok, I'd guess you're around 700gph or so into the tank and I agree that 1.5 inch down should be just fine.  I would try to open the hole a bit more to allow more air into the pipe...  My hole is about 1/8th inch diameter I believe, but if you can increase in the smallest possible increments it's idea until you find the magic point... its so hard to dril a hole smaller.

[OttawaReefer]

... its so hard to dril a hole smaller.

But then I could spend a lot more time at home depot looking for a reverse drilling bit 

I ended up drilling the whole larger two more times.  I can't remember the exact size of drill bit that I ended up using but once it stabilizes it's usually quiet.  After I stick my arms into the tank and I push more water through the overflow it usually takes a while for the flow to stabilize again.

Thanks for all the help with the overflow.  Who knew that in the end.....size really did matter.

[lost_at_sea]

This looks like kinda mix between a durso and a full siphon drain.

What's the reason for the 90' downturn on the pipe? I'm thinking there maybe an airpocket stuck somewhere there that restricts movement until the flow stabalizes, maybe?

I'd be curious to see if the drain goes quiet if you remove the 90' and just have it open.

[OttawaReefer]

I couldn't find a T-junction that had threads on it to do a proper durso.  Since I drilled a hole at the top/rear part of the external elbow (the hole is about 2-3mm in diameter) it's been very quiet.

[Hookup]

But then I could spend a lot more time at home depot looking for a reverse drilling bit 

I ended up drilling the whole larger two more times.  I can't remember the exact size of drill bit that I ended up using but once it stabilizes it's usually quiet.  After I stick my arms into the tank and I push more water through the overflow it usually takes a while for the flow to stabilize again.

Thanks for all the help with the overflow.  Who knew that in the end.....size really did matter.

Glad it all worked out...  Now I'll go read your other thread about your sump problem.. LOL...

[OttawaReefer]

Glad it all worked out...  Now I'll go read your other thread about your sump problem.. LOL...

Yeah, seems that I had a problem on both ends 


The only thing beefing me about the overflow is that it occassionally burps up some water from the hole.  I'll look at cementing an extra bit of tube or something on there someday.