How much elbows cut flow....? Swapping sumps..

[ShawnSaucier]

Happy New year everyone. So I’ve been in the process of upgrading/ modding my filtration and heading towards Triton method. I plumbed my new sump and added the Apex FMK in-line to see what my return was pushing. I was shocked that I’m only getting 706 gph from a pump that is supposedly pushes 2100 gph. The output is 3/4” and my plumbing is all 1” with a reduction at the output. There are three 90’s inline from the pump before the FMK monitor only because the spacing is tight and 45*s wouldn’t work.
I have calibrated the pump 3 times hoping it was a mistake, and I don’t believe you can calibrate the FMK unit..?
Added some pics, sorry for the mess, I’m still wiring but this kinda stopped me in my tracks last night. Not sure if I need a bigger pump, but I need to get closer to the 1700 gph Mark. Any help please..

 

[TheEngineer]

It is something like 2.5’ of head for each 90 elbow. Add in the run and rise of your plumbing and you’re probably around 10’ of head loss. Then all those other bends you have after add more.

I count 4 90 elbows and 2 45 elbows just in that picture. There’s probably one more 90 at the tank. That adds up.

What pump are you using?

 

[ShawnSaucier]

It is something like 2.5’ of head for each 90 elbow. Add in the run and rise of your plumbing and you’re probably around 10’ of head loss. Then all those other bends you have after add more.

What pump are you using?

I’m using an Ecotech M1.. What about soft plumb to the sump bulkhead? That would remove 2x90’s. My off set overflow has been a pain since day 1, lol.

 

[Idoc]

BRStv did a video on whether it was real or myth that 90 degree elbows restricted flow...if so, they wanted to give an estimate of flow loss for each type of elbow. Surprisingly... minimal to no loss was found when they measured flow with or without 90 degree elbows! Look up the video on their website...

My guess is your losing the flow due to head pressure and/or restriction to smaller diameter piping. Are you using loc-line with a nozzle? If so, that is a huge reducer...I can feel a huge difference from what cones out of my nozzle vs not having any loc-line!

 

[TheEngineer]

BRStv did a video on whether it was real or myth that 90 degree elbows restricted flow...if so, they wanted to give an estimate of flow loss for each type of elbow. Surprisingly... minimal to no loss was found when they measured flow with or without 90 degree elbows! Look up the video on their website...

My guess is your losing the flow due to head pressure and/or restriction to smaller diameter piping. Are you using loc-line with a nozzle? If so, that is a huge reducer...I can feel a huge difference from what cones out of my nozzle vs not having any loc-line!

I’d be interested to see that. Loss from fittings is well used within the plumbing industry. Seems like someone would have noticed it wasn’t needed at some point

 

[ShawnSaucier]

BRStv did a video on whether it was real or myth that 90 degree elbows restricted flow...if so, they wanted to give an estimate of flow loss for each type of elbow. Surprisingly... minimal to no loss was found when they measured flow with or without 90 degree elbows! Look up the video on their website...

My guess is your losing the flow due to head pressure and/or restriction to smaller diameter piping. Are you using loc-line with a nozzle? If so, that is a huge reducer...I can feel a huge difference from what cones out of my nozzle vs not having any loc-line!

So the output of the pump is 3/4”, this is plumbed into 1” piping. At the top of the return there is a “y” into two 3/4” loc-lines with no nozzles

 

[ShawnSaucier]

I had assumed some reduction, but not 60%

 

[ShawnSaucier]

And this is within 24” from the pump to the flow meter, if not less

 

[TheEngineer]

The loss isn’t just to the FMK. It is the whole length of pipe until the water exits.

 

[ShawnSaucier]

The loss isn’t just to the FMK. It is the whole length of pipe until the water exits.

I agree, but from the point that the monitor is at I already have lost 60%

 

[Fin]

 

[TheEngineer]

I agree, but from the point that the monitor is at I already have lost 60%

It isn’t just up to that point. You are measuring the entire length. Think about it like a straw. If you pinch any part of the straw, the flow through the whole thing slows down. Not just before the pinch.

 

[ShawnSaucier]

True. I had hoped that going the 1/4”larger on the piping would help with the reduction

 

[Idoc]

I’d be interested to see that. Loss from fittings is well used within the plumbing industry. Seems like someone would have noticed it wasn’t needed at some point

Yes, I have always assumed this as well. I wonder if it has to do with the lower pressures we deal with versus other industries with higher pressures and maybe more turbulent flows? My specialty is with the eyes, so kind of guessing here, lol. I'll try to find that video.

 

[ShawnSaucier]

Just wondering how much flow I would gain if I removed 80% of the fittings

 

[Idoc]

I’d be interested to see that. Loss from fittings is well used within the plumbing industry. Seems like someone would have noticed it wasn’t needed at some point

@Fin found and posted the video...i guess i didn't recall the video very well. It is testing flow reduction difference between using 90 degree elbows vs 2 45 degree elbows. Interesting though, shoes minimal differences in reduction from the stated gph in the pump for lower gph pumps but greater reduction from higher gph pumps! I guess maybe their is some sort of turbulence or something creating loss at higher pressures and not letting the pump fiction at maximum efficiency. But, the video does show that the lower gph pumps really didn't show much reduction in pressure compared to their advertised output with the 90 degree elbows... but the higher goh pumps did.

 

[ShawnSaucier]

@Fin found and posted the video...i guess i didn't recall the video very well. It is testing flow reduction difference between using 90 degree elbows vs 2 45 degree elbows. Interesting though, shoes minimal differences in reduction from the stated gph in the pump for lower gph pumps but greater reduction from higher gph pumps! I guess maybe their is some sort of turbulence or something creating loss at higher pressures and not letting the pump fiction at maximum efficiency. But, the video does show that the lower gph pumps really didn't show much reduction in pressure compared to their advertised output with the 90 degree elbows... but the higher goh pumps did.

The higher pumps were going through a reduced pvc diameter though, I thought. So I can understand the dramatic reduction in gph

 

[Idoc]

Have you thought about using flex pvc to get rid of almost all those fittings?

 

[ShawnSaucier]

That was a thought,

 

[mfinn]

One thing I remember reading about the Vectra pumps is the flow rating was done with the optional BST to slip pvc fittings.
So if you used the blue collar right off the pump you are creating a restriction at the pump, even though you used 1" after.