Overflow pvc pipe size-1” bulkhead to 1.5”pvc?

[michaelallff]

My overflow bulkhead is 1 inch on the back. I am getting a lot of noise when the water hits the bottom of the pvc when it makes its 90 degree turn towards the sump. I thought that by using 1.5 pvc that I would reduce friction and speed up the overflow. But I am thinking not. Should I just go back to 1 inch pvc and will this reduce the water noise?

 

[SWINGRRRR]

Google reverse duroso. Go all the way down with 1" then at the bottom, the duroso, make it as big as possible to give the water area to slow down.

 

[uncleof6]

The issues with air/water drain systems are all caused by the same inherent flaw: They are low flow systems, and the flow rate is too high. Ultimately the solution to ALL issues with these systems is to slow the flow rate till the flow is laminar (non-turbulent.) Restrictions such as valves, and elbows exacerbate the problems (the noise you are hearing is caused by turbulence in the 90) Good design, has the drain line as straight as possible. Eliminate the 90, and use 2-45° fittings to get under the stand to the sump, and drop straight into the sump from the last 45. This will quiet the system a bit. The "laminar" flow rate can be variable, for a lot of reasons, but for 1.5" is ~<320gph. Trying to increase the flow rate, simply again, will exacerbate the problems. There are a number of "gimmick" fixes out there, but to jump your flow rate up, and have a silent and trouble free system, you need to think in terms of a safe siphon system.

Jim

 

[FLSharkvic]

The issues with air/water drain systems are all caused by the same inherent flaw: They are low flow systems, and the flow rate is too high. Ultimately the solution to ALL issues with these systems is to slow the flow rate till the flow is laminar (non-turbulent.) Restrictions such as valves, and elbows exacerbate the problems (the noise you are hearing is caused by turbulence in the 90) Good design, has the drain line as straight as possible. Eliminate the 90, and use 2-45° fittings to get under the stand to the sump, and drop straight into the sump from the last 45. This will quiet the system a bit. The "laminar" flow rate can be variable, for a lot of reasons, but for 1.5" is ~<320gph. Trying to increase the flow rate, simply again, will exacerbate the problems. There are a number of "gimmick" fixes out there, but to jump your flow rate up, and have a silent and trouble free system, you need to think in terms of a safe siphon system.

Jim

Did you know that 2 45 Elbows has the same restrictions as 1 90 elbow?

 

[FLSharkvic]

45's only on the returns !

45's only on the returns !

Drains are 90's..

 

[SFish]

It does not have the same effect on a gravity feed pipe as one that is being feed by a pump. Also horizontal runs on an overflow cause problems. In any case the point was to change the system to a Bean Animal or Herbie style. The set up you have is known for problems.

 

[Lsufan]

If u make a 90 with 2 45’s then yes. I’m pretty sure that what uncle meant was to replace 2 90’s with 2 45’s. People will place a 90 to get under the stand then another 90 to get back square with the sump. What uncle meant was to use a 45, run the pipe on the 45 degree angle until u get to where u need to be, then use another 45 to get square with the sump. So u use 2-45’s instead of 2-90’s. He wasn’t referring to making a 90 with 2 45’s.

 

[outy]

I thought that by using 1.5 pvc that I would reduce friction and speed up the overflow.

Nope just adds more room for the water to slosh around creating noise.

I have 1" returns and I used 45's and its the amount of water you have gong through that's making the noise.

I have about 500gph going through 2 1" drains and its noisy, so I wrapped the pipes in old towels and it made the noise almost disappear.

I thought the trick would be to use the black drain pipe pvc designed for drain pipes and noise. I have not tried it yet. Not sure what you have, the white pressure rated pipe is not designed for air and water so for noise's you have to insulate.

 

[Lsufan]

I hope he figured it out by now, the op was from 7 years ago.
I’m just messing with u outy, I don’t look at the dates often eighther. FLsharkvic must have found this in the archives.

ABS (which is the black drain pipe) won’t help on any noise. The reason it is drain pipe is because neighther the pipe or fittings is rated for pressure. They do make the black pipe insulation up to 1” that may be better then using towels.

 

[SFish]

Or you could use a full siphon.

 

[outy]

the pipe or fittings is rated for pressure. .

There is no pressure at all

 

[Lsufan]

I know, I was just stating why abs is only drain pipe. Most people’s systems don’t have to have pressure rated pvc at all, even on the returns. Not much pressure on most systems

 

[outy]

I'm just messing with u outy,.

Good things about this forum, is when people attack a problem they google these things and search for solutions.

Have done it myself many times. Collective knowledge is priceless.

OP may be long gone but this problem common.