Return plumbing size

[fishstix]

I have a PVC hybrid sump, that drilled for one inch returns. The tank is 220 gallons, with a return drilled on each side it 1 inch each. I am using return pump for each one and was going to run 1 inch PVC from each pump to the bulkhead that goes into the tank on each side.

Will one inch PVC be OK for this? The pumps are rated at 2200 GPH each.

Thanks

 

[Crabs McJones]

at 2200 gallons per hour each, for one inch pvc, you're going to be right on the line of what the pipe can handle. With that being said, 2200 gallons per hour per pump probably isn't figuring in loss from head pressure. So you should be ok with 1" but i'd maybe consider bumping up to 1 1/4 or even 1 1/2 just to be safe.

 

[fishstix]

at 2200 gallons per hour each, for one inch pvc, you're going to be right on the line of what the pipe can handle. With that being said, 2200 gallons per hour per pump probably isn't figuring in loss from head pressure. So you should be ok with 1" but i'd maybe consider bumping up to 1 1/4 or even 1 1/2 just to be safe.

Thanks for the advise, would it be OK, to increase up to 1 1/4 even though it has to go into 1" bulkhead coming out of the sump and into the back of the tank?

 

[Crabs McJones]

Thanks for the advise, would it be OK, to increase up to 1 1/4 even though it has to go into 1" bulkhead coming out of the sump and into the back of the tank?

If the bulkhead is already one inch, theres not really a point to making your pipe 1 1/4 as the water still has to squeeze through the 1" bulkhead. Are the pumps adjustable? I'd run 1" and turn them down slightly so you're not at the max.

 

[fishstix]

If the bulkhead is already one inch, theres not really a point to making your pipe 1 1/4 as the water still has to squeeze through the 1" bulkhead. Are the pumps adjustable? I'd run 1" and turn them down slightly so you're not at the max.

Yes the bulkheads are already 1" out of the sump and the back of the tank. They came that way, really don't want to have them changed. Yes I can turn the pumps down. They are the Neptune systems COR-20

Thanks for your help

 

[mfinn]

Is the pump external?
If it is, what is the plumbing size on the suction side?

 

[Crabs McJones]

Yes the bulkheads are already 1" out of the sump and the back of the tank. They came that way, really don't want to have them changed. Yes I can turn the pumps down. They are the Neptune systems COR-20

Thanks for your help

Yeah, if you don't want to drill for bigger bulkheads, that'd be the way to go

 

[MSOEME2009]

There are a few things you'll need to know. I will use a Sicce Syncra Silent 5.0 as an example. A 5.0 is rated at 1321 GPH and 12.5' TDH (total dynamic head).

1) How high is the outlet from where the pump sits. This is your overall head loss in feet. Fighting gravity is the largest loss in pumped systems. This is your major loss.
2) How long is your piping system in total feet. This is straight runs of pipe and elbows, valves, ect. To make it simpler on you, estimate a 90 as 5.2 feet, a check at 11 feet. Add that all together.
3) Find your pump manufacturers "curve" this will be a graph with the vertical axis being head (Feet) and the horizontal axis being flow (GPH). Once you have located that, find your major loss. I will use 6.5' for this example. The 6.5' vertical axis line intersects with the 5.0 curve at 900 GPH.
4) Use this "actual" flow rate to calculate your minor losses now. I will assume you are using schedule 40 pipe. A 1" Schedule 40 pipe with 900 GPH (15 GPM) has a head loss of 5.5 psi per 100' or 12.8'. Lets assume you have 50' of total length of pipe (fittings, valves, line). This would be 2.75 psi per 100' or 6.4'.

Look at friction loss (ft/100ft), that's the loss from moving water.

https://www.engineeringtoolbox.com/pvc-pipes-friction-loss-d_802.html

5) Adding 6.5' + 6.4' = 12.9'; We have choked our flow. 1" is too small, you'll only have about 100 GPH. Simply looking at 1-1/4" or 1-1/2" you can see 3.3' per 100' or 1.5' per 100'. This would allow our pump to flow either 700 GPH (1-1/4 using 50') or 850 GPH (1-1/2 using 50').

6) Remember you can always run larger pipe after the pump, and then neck down to fit your outlet pipe requirements.

Let me know if you have any questions.

 

[fishstix]

Is the pump external?
If it is, what is the plumbing size on the suction side?

The pump is internal, the intake is 1.5 ", the exit is 1 1/4, which will need to go into a 1" bulkhead to exit the sump.

 

[fishstix]

There are a few things you'll need to know. I will use a Sicce Syncra Silent 5.0 as an example. A 5.0 is rated at 1321 GPH and 12.5' TDH (total dynamic head).

1) How high is the outlet from where the pump sits. This is your overall head loss in feet. Fighting gravity is the largest loss in pumped systems. This is your major loss.
2) How long is your piping system in total feet. This is straight runs of pipe and elbows, valves, ect. To make it simpler on you, estimate a 90 as 5.2 feet, a check at 11 feet. Add that all together.
3) Find your pump manufacturers "curve" this will be a graph with the vertical axis being head (Feet) and the horizontal axis being flow (GPH). Once you have located that, find your major loss. I will use 6.5' for this example. The 6.5' vertical axis line intersects with the 5.0 curve at 900 GPH.
4) Use this "actual" flow rate to calculate your minor losses now. I will assume you are using schedule 40 pipe. A 1" Schedule 40 pipe with 900 GPH (15 GPM) has a head loss of 5.5 psi per 100' or 12.8'. Lets assume you have 50' of total length of pipe (fittings, valves, line). This would be 2.75 psi per 100' or 6.4'.

Look at friction loss (ft/100ft), that's the loss from moving water.

https://www.engineeringtoolbox.com/pvc-pipes-friction-loss-d_802.html

5) Adding 6.5' + 6.4' = 12.9'; We have choked our flow. 1" is too small, you'll only have about 100 GPH. Simply looking at 1-1/4" or 1-1/2" you can see 3.3' per 100' or 1.5' per 100'. This would allow our pump to flow either 700 GPH (1-1/4 using 50') or 850 GPH (1-1/2 using 50').

6) Remember you can always run larger pipe after the pump, and then neck down to fit your outlet pipe requirements.

Let me know if you have any questions.

Thanks for the info.
Each line will be about 5 feet from the sump into the tank. The exit of the pump is 1 1/4 which goes into 1" which is inside of the sump, then exits the sump at 1", it would be better to increase to 1 1/4 where it comes out of the sump and goes up to the tank to 1 inch?

I can do either way, I was just not sure the back everything 1 inch if it would add and benfit, I guess that what I am confused about.

Thanks for your help.

 

[MSOEME2009]

I'd recommend making your holes bigger, that's just me. At a minimum you'll need to neck to fit, and neck back up. Otherwise you won't have much flow, and that 2200 GPH pump just turned into a 500 GPH.

 

[MSOEME2009]

Going larger anywhere you can helps because it reduces the fluid velocity. The smaller the diameter, the higher the velocity, the higher the pressure drop.

If you end up having 10' of 1" in the system your losses will be a lot less than 100' of 1". (i.e 4.6' vs 46')

 

[mfinn]

The pump is internal, the intake is 1.5 ", the exit is 1 1/4, which will need to go into a 1" bulkhead to exit the sump.

Nevermind.
I was just going to say that if it was 1-1/2 suction side and you were choking it down to 1", there would be stress on the pump that most manufactures say is bad for it.
On the output side, it's just like adding more head height.

Another thing to consider, do you plan on using loc-line inside the tank? 3/4" is the biggest size they make.

 

[fishstix]

Nevermind.
I was just going to say that if it was 1-1/2 suction side and you were choking it down to 1", there would be stress on the pump that most manufactures say is bad for it.
On the output side, it's just like adding more head height.

Another thing to consider, do you plan on using loc-line inside the tank? 3/4" is the biggest size they make.

Yes does have loc-line inside of the tank.

So since I cannot make the holes out of the sump larger, don't want to risk drilling the tank or the sump, my best option would be come out of the sump with the 1" into the 1" bulkhead, then go to 1 1/4 and back to the 1" which goes into the tank?

Is that what everything is my best option at this point? Just checking before I order all my plumbing parts?

Thanks

 

[mfinn]

Yes does have loc-line inside of the tank.

So since I cannot make the holes out of the sump larger, don't want to risk drilling the tank or the sump, my best option would be come out of the sump with the 1" into the 1" bulkhead, then go to 1 1/4 and back to the 1" which goes into the tank?

Is that what everything is my best option at this point? Just checking before I order all my plumbing parts?

Thanks

I would just stay at 1" all the way. Keep it as simple as possible.
You are going to have to use a 3/4" to 1" reducing bushing on the inside of the tank to accommodate the 3/4" loc line.

 

[Crabs McJones]

I would just stay at 1" all the way. Keep it as simple as possible.
You are going to have to use a 3/4" to 1" reducing bushing on the inside of the tank to accommodate the 3/4" loc line.

Agreed

 

[MSOEME2009]

All depends on what flow rate you are happy with. I use pumps that have 8" outlets and will have to go back up to 14" on the pipe to avoid pressure drop/loss based on the system it's going into.

If your pipe system can't change, maybe your pump can (not sure of your situation). Sometimes a higher head pump is needed if the system can't be changed.

 

[fishstix]

After seeing this, and the fact I cannot change the holes out of the sump and into the tank, really cannot change pumps either, as they are brand new. With that all that being said, should I just go with the 1"? I feel rather confused.

 

[MSOEME2009]

Based on the chart you gave. You can already go to the 5' mark based on what you said earlier; ~1500 GPH. At 1" line, that's 32.9' per 100'. I'll assume you have 4 90s, a valve, a check, and 10' of pipe; 20+10+10 = 40' or 0.4 * 32.9' = 13.2'

Add 13.2' + 5' = 18.2' and you are at 200 GPH to your tank.

Not trying to be negative, but I don't think you'll be happy with that.

 

[MSOEME2009]

Simply going to 1-1/4 is going to give you 8.8' of total loss or almost 1000 GPH of flow (not counting your 1" bottle necks).