Overflow Plumbing Issues

[usmcarty42]

A few months ago I asked a LFS to come in and do some sump upgrades, put some hardline in, etc. They ended up replacing the overflow which came with the tank and generally did a pretty poor job.

I went from an overflow I could never hear to one that is insanely loud; and the tank is in the living room.

I'm not sure if they went with a decreased diameter (which seems unlikely) or what they did. Is there a standard formula for the overflow size?

 

[UncommonSense]

There isn’t really a single chart or “rule of thumb” for overflows, as they come in numerous permutations, and plumbing arrangements!

This overflow noise could honestly be as simple as an incorrectly adjusted valve, but that’s not easy to determine without info such as:

— type of overflow box ? (Internal, external)

— how many drain pipes come out from the overflow box? (1,2,3)

— what size is the plumbing?

— what sump return pump is the system using?


And so on… if you aren’t sure, some photos might help us extrapolate!

 

[Mebbid]

Not a formula specifically, it all depends on the overflow size. How is your overflow set up? There's a handful of different styles of overflows and when they are noisy it's usually a pretty simple fix.

 

[mmorrison55]

When My overflow all of a sudden became loud, I found that it was my weir had calcified buildup and after I took a stiff brush and brushed the weir good, the noise went away.

I agree with the others that it’s hard to diagnose. If you noticed the increase in noise immediately after they swapped out your plumbing, it’s possible it went from metric size pipes to us/imperial size and yiu just need to adjust your valves and/or your return pumps to redial everything in.

I just had to increase my return pumps a bit last night as the water level in my overflow box had gotten lower and was not above the main drain pipe. I think this is a sign that my return pumps need cleaning.

Btw, I have a “herbie” style overflow.

You didn’t mention what kind of overflow you have, so it may help to diagnose if we know.

If you can remove your overflow lid, can look down in it, how many pipes do you see? And where is the water level in relation to each of the pipes?