jtveach
Supporting Member
Oh yeah, that looks good. Just bummed cause I brought pvc to match my trigger sump but may have to just get over it.I’ve done it both ways. I prefer 45’s or double 45’s. I’ve had 90’s that seem to be fine and others restrict flow due to air trapping in the horizontal run. Not sure why some seem unaffected. Maybe you can dry plumb it and give it a try both ways and see which way is working better. Don’t be scared to use flexible PVC if needed. It’s great stuff and always an option too.
There is next to no impact to flow rates when using 90's vs 45's. Especially when you factor in the total flow rate the system will have when in operation. The maximum flow rate at gravity or low pressure on a 1" line is only about 960 GPH or 16 GPM and most systems run are dialed in at best 1/2 the total flow rate capable of the pipe capacity. So any potential loss in total flow by using 90's instead of 45's won't really matter.
BRS also tested this and saw no real significant difference in total flow between using 90's or 45's. So I'd say use what ever you like to make you happy with the piping install.
Wow, great info. Thanks for that. I had already made the decision to go with 90's and ordered them. I feel much better now knowing that it's not going to make a difference.
I will play around with the configuration until I find what works best. It may just mean I forego what I feel is the cleaner look and use flex pipe instead. Appreciate everyones input. One reason I love this hobby is that there is always more than one way and it gives opportunities for experimentation and learning.I don’t believe that the flow rate is what you really need to be worried about. It’s the air pockets in the horizontal runs that can sometimes form. I’ve had a few tanks that do fine, and then the next tank seems to have issues. My current tank has some horizontal runs and I do get a little air trapping when the system is shut down and restarted, but it eventually works the air out. If it doesn’t, I just turn the main drain valve wide open to flush the air out which seems to work.
I find it comical how three out of four have proved what everybody has said for years, but Ryan brushes it off as “insignificant.” I just lost respect for that study. It’s pretty much common sense. If you have a lot of turns vs a straight run...it will slow down flow.
When direction is changed from straight to curved (90 degrees), this will cause friction and turbulence. As a result...reduced flow.
Here’s a very easy way to understand it:
Two people behind the wheel of Lamborghini’s are about to race. Both tracks are exactly one mile. However...one track has twenty...ninety degree turns, but the other track is a straight run. Who do you think will have the better time? Exactly.
Back to the real issue. Air trapping.
Numerical Investigation on Fluid Flow in a 90-Degree Curved Pipe with Large Curvature Ratio
In order to understand the mechanism of fluid flows in curved pipes, a large number of theoretical and experimental researches have been performed. As a critical parameter of curved pipe, the curvature ratio <svg xmlns:xlink="http://www.w3.org/1999/xlink"...www.hindawi.com
I don’t believe that the flow rate is what you really need to be worried about. It’s the air pockets in the horizontal runs that can sometimes form. I’ve had a few tanks that do fine, and then the next tank seems to have issues. My current tank has some horizontal runs and I do get a little air trapping when the system is shut down and restarted, but it eventually works the air out. If it doesn’t, I just turn the main drain valve wide open to flush the air out which seems to work.
I find it comical how three out of four have proved what everybody has said for years, but Ryan brushes it off as “insignificant.” I just lost respect for that study. It’s pretty much common sense. If you have a lot of turns vs a straight run...it will slow down flow.
When direction is changed from straight to curved (90 degrees), this will cause friction and turbulence. As a result...reduced flow.
Here’s a very easy way to understand it:
Two people behind the wheel of Lamborghini’s are about to race. Both tracks are exactly one mile. However...one track has twenty...ninety degree turns, but the other track is a straight run. Who do you think will have the better time? Exactly.
Back to the real issue. Air trapping.
Numerical Investigation on Fluid Flow in a 90-Degree Curved Pipe with Large Curvature Ratio
In order to understand the mechanism of fluid flows in curved pipes, a large number of theoretical and experimental researches have been performed. As a critical parameter of curved pipe, the curvature ratio <svg xmlns:xlink="http://www.w3.org/1999/xlink"...www.hindawi.com