Installing my new Sequence 750 pump

[miamicuse]

No. That’s the total equivalent pipe length.

You have 6’ of static head + about 5’ of dynamic head (200’ of pipe @ 2.6’ of head per 100’ of pipe) for a total of 11’ of head.

Thank you for setting me straight.

So for PIPE RUN FRICTION LOSS I have 80', and for fittings I have 180'. Total is 260', if I use 2.6' per 100', I end up with 4.68' of dynamic head, or 5' rounded up. Add to the 6' of static head that's 11' total.

Thank you much appreciated.

 

[GBBUDD]

don't forget the suction ecoefficiency.

 

[miamicuse]

I think you have to go back to the issue of having your water source so far from the pump. As @combatwombat calculated the head that would still be within the specs of the Sequence pump. You would never have 194 feet of head, when you look at the PerformancePro specs for all their pumps the biggest pump is 3hp and that lists max head at 94 ft, so you know you are far off in the calculations.
You know the Sequence struggled with the setup but the head is within its specs (what I had calculated yesterday with an online calculator without knowing all the details of your setup was surprisingly close to @combatwombat calculation). I dont have enough experience to know if 30 feet from the source is common, I dont think I have seen that too often when I have researched pond setups. And it could be the combination of the distance and how many 90 degree fittings you have between the water source and the pump. Twenty-two 90 degree elbows seems like a lot, I only have one in my setup so I may not be the norm in that regard. So I guess it might be going back to the drawing board to see if you can re-position the pump.

I will say the run is not only long, but also has up and down, plus a lot of elbows, plus my insistence in using hard 90 pressure elbows instead of the sweeping radius gravity drain elbows, all played a role.

The calculations end up being 11' head, the Sequence pump has a max of 12' head. But then again, the 3600GPH and 12' head are probably "ideal laboratory conditions". If it is pushing the highest flow of 3600GPH, the velocity in the pipe will increase and all these friction losses will also increase. Someone said as the pump gets older, as the water contain more debris like seeds leaves debris it will get worse. I think the conclusion with this is the Sequence pump is marginal for what I need.

As far as relocating the location of the pump, unfortunately that is something that is not easy to do.

Firstly, this was an existing configuration, and it was working at one time, so while it may not be ideal, I know it's not impossible.

Secondly, there has been many considerations given to how the pipe was run. Here is a picture of what I got. Both the intake (red) and return (blue) line hides\ under the bridge. So one consideration was to not have so much white PVC pipe exposed (yes I know I can paint it green and it probably will be covered in algae).

Thirdly, both lines have to be buried six inches below grade because that path will be covered with concrete pavers. The pump is just around the corner of the building, where the roof overhang is wider to protect the pump from being poured onto when raining and also out of the sun.

Fourthly, it was a big chore on my elbows and knees in the crawlspace to run a 30' long cable from the panel to that spot around the corner for a dedicated 120V circuit for this pump. It was using another circuit that was overtaxed with security motion lights, exterior sconces, security cameras, driveway gate motors etc...so I already have water, electric, weather protection around that corner for the pump.

In the event I can't get an external pump to work with what I got, my plan B would be to use a submersible pump under the bridge. I already know the small utility pump can do that with no issue.

 

[miamicuse]

don't forget the suction ecoefficiency.

OK what is the suction coefficient.

 

[GBBUDD]

JUST A MIND GAME I HAD TO THROW THAT IN . YOUR GOOD LOL

 

[combatwombat]

Suction coefficient is the time it takes @GBBUDD to suck a watermelon through a paper straw at at a given level of rage. You have to multiply it by the length of your longest koi.

 

[GBBUDD]

Suction coefficient is the time it takes @GBBUDD to suck a watermelon through a paper straw at at a given level of rage. You have to multiply it by the length of your longest koi.

AND DETERMIN THE RANGE YOU'LL NEED TO RUN TO, TO AVOID THE BERAGE OF WATER MELLON SEEDS AND YOU WON'T CATCH ME USING A PAPER STRAW NO RANGE GIVE ME THE GOOD OLD MCDONALD DOUBLE WIDE

 

[combatwombat]

AND DETERMIN THE RANGE YOU'LL NEED TO RUN TO, TO AVOID THE BERAGE OF WATER MELLON SEEDS AND YOU WON'T CATCH ME USING A PAPER STRAW NO RANGE GIVE ME THE GOOD OLD MCDONALD DOUBLE WIDE

Paper straw is what produces consistent rage, which is why it’s used for scientific measurement.

 

[miamicuse]

JUST A MIND GAME I HAD TO THROW THAT IN . YOUR GOOD LOL

you got me I googled that and I saw some fancy equations LOL!

 

[Pablo]

For a moment there I thought there was going to be another infamous discussion like the one of going from 2 inch pipe to a 1 inch pipe or vice versa.

 

[Pablo]

I will say the run is not only long, but also has up and down, plus a lot of elbows, plus my insistence in using hard 90 pressure elbows instead of the sweeping radius gravity drain elbows, all played a role.

The calculations end up being 11' head, the Sequence pump has a max of 12' head. But then again, the 3600GPH and 12' head are probably "ideal laboratory conditions". If it is pushing the highest flow of 3600GPH, the velocity in the pipe will increase and all these friction losses will also increase. Someone said as the pump gets older, as the water contain more debris like seeds leaves debris it will get worse. I think the conclusion with this is the Sequence pump is marginal for what I need.

As far as relocating the location of the pump, unfortunately that is something that is not easy to do.

Firstly, this was an existing configuration, and it was working at one time, so while it may not be ideal, I know it's not impossible.

Secondly, there has been many considerations given to how the pipe was run. Here is a picture of what I got. Both the intake (red) and return (blue) line hides\ under the bridge. So one consideration was to not have so much white PVC pipe exposed (yes I know I can paint it green and it probably will be covered in algae).

Thirdly, both lines have to be buried six inches below grade because that path will be covered with concrete pavers. The pump is just around the corner of the building, where the roof overhang is wider to protect the pump from being poured onto when raining and also out of the sun.

Fourthly, it was a big chore on my elbows and knees in the crawlspace to run a 30' long cable from the panel to that spot around the corner for a dedicated 120V circuit for this pump. It was using another circuit that was overtaxed with security motion lights, exterior sconces, security cameras, driveway gate motors etc...so I already have water, electric, weather protection around that corner for the pump.

In the event I can't get an external pump to work with what I got, my plan B would be to use a submersible pump under the bridge. I already know the small utility pump can do that with no issue.

Wow that was a lot of work in a tight space, do not envy you. Going to look great though once you get it going. Totally understand not wanting to have to re-do that work.

 

[GBBUDD]

you got me I googled that and I saw some fancy equations LOL!

Oh it does exist but not to the degree we play at

 

[GBBUDD]

II

Paper straw is what produces consistent rage, which is why it’s used for scientific measurement.

Ever see titanic when the kid from the streets tries to teach the proper girl how to spit ?

Well ill take my double wide 1980 McDonald's plastic straw to spit out my Mellon seeds. You can beet the range or accuracy.

 

[miamicuse]

OK based on my current calculations, assuming a flow rate of 1200GPH, I need a pump with a 12.76' of head, say 13' even.

Now, with all these pipe sizes lengths and fittings calculations, I do feel that there are losses unaccounted for.

For example, what about the 3" diameter 36" basket strainer at the intake? I cut it off once I had trouble with the Sequence pump so I can feed a hose to force air out of the line. But that basket strainer has hundreds and hundreds of narrow slits. That has to be some friction loss with using it.

Another example, the pipe goes from 1-1/2" to 2" into the 9" tall priming pot, and went back down to a 2" short pipe and adapter before entering the motor cavity, through the impeller, then discharged out of the 1.5" outlet at the top. That has to be quite a bit of energy loss from this as well.

How do I account for these additional losses that don't seem to show up on charts?

or do I just say double the head calculated to be on the safe side?

I guess I am now looking for a self priming pump with at least a 26' head. Any suggestion?

 

[GBBUDD]

1200 gph in for a small fountain or goldfish bowl. Not for a set up requiring 11 feet of head and 100 feet or more of piping.