Noisy Gurgling Overflow - SOLVED!!!!

[banditpowdercoat]

Your vent hose is to large in Diameter. It's not matching the drain size to the cap hole, but matching the cap hole to the flow requirements. I have 6 0.018" holes in my cap for venting, about 300GPH drain. and it's silent. Try getting a shutoff on the vent, something you can precicely throttle back untill it's silent.

[mark]

Originally Posted by banditpowdercoat

Your vent hose is to large in Diameter. It's not matching the drain size to the cap hole, but matching the cap hole to the flow requirements. I have 6 0.018" holes in my cap for venting, about 300GPH drain. and it's silent. Try getting a shutoff on the vent, something you can precicely throttle back untill it's silent.

found with my 2" Dursos running between 500 and 1000gph, hole size in each is only around 1/8"

[Tom R]

I find that using Spaflex tubing helps muffle the sound. Spaflex tubing is available at most Hot Tub stores if they do installation.

Tom R

[Ron99]

Thanks for all the input. I have tried to replicate the valved vent by drilling a larger hole then taping it closed and using a pin to slowly enlarge a hole in the tape. All it does is affect the height of the water in the overflow box but little to quiet the gurgling. I'm not sure using solid pipe or spaflex will help muffle noise as it seems to be the gurgling of air at the T that is then being amplified in the T itself and sounding loud if that makes sense. But I may give it a try.

dkcrx, it looks like you have your pipe at about a 45 degree angle. This is why I used flexible tube as I need to go to the opening in the stand that is in the middle but the overflow is on the side. So I may need to angle the pipe as well and then use a couple of 45 degree elbows to get into the stand and sump. Would you mind posting a picture of the your configuration at the sump as well?

But as I said, most of the noise seems to be the gurgling at the T where the air/water interface is fairly turbulent and alot of air is being sucked down into the plumbing.

[Ron99]

Also, do you guys run the same diameter pipe all the way down from the bulkhead or do you decrease it at some point?

Thanks.

[whatcaneyedo]

Your overflow looks like mine... I've got some time off coming up soon so I'm just going to put everything from my display tank into the sump and bring the tank into a glass shop to get a second hole drilled for a herbie style overflow.

[dkcrx]

Originally Posted by Ron99

Also, do you guys run the same diameter pipe all the way down from the bulkhead or do you decrease it at some point?

Thanks.

Same size all the way to the sump, and I have one 90deg turn in the pipe

[achilles101]

I have the same tank I did an external durso drilled hole in cap to 1/4 it was noisey so used silcone to make smaller about 1/8. It had 2in sch 40 pvc pipe on it when I bought in but I used 2in sch 40 pvc for durso and then went to flexible 2in pipe for ponds. It is quiet and Im flowing about 900gph. Much like dkcrx's but not at angle.

[golf nut]

Originally Posted by Ron99

Also, do you guys run the same diameter pipe all the way down from the bulkhead or do you decrease it at some point?

Thanks.

That looks like the cause of your problem, your overflow is becoming a syphon due to the number of reductions you have made with adapters.

[chris121277]

I would try throttling back your return pump.......I have HOB over flow that claims to be rated for 1200 gph, and I tried everything to make it quite.
The only thing that worked for me was to back off the return pump to about half.

Here is a great article on reducing the noise from your overflow

http://www.wetwebmedia.com/SystemPIX...Oneinchart.htm

Hope that helps