Installing my new Sequence 750 pump

[miamicuse]

The new Sequence 750 pump and the priming pot arrived so I started to try installing them.

A couple of initial observations.

(1) the pump is smaller and lighter than I expected, and comes with a cord, so I don't have to do any hard wiring so from that stand point is a good thing.

(2) the priming pot does not have a flat bottom so it's not going to sit nicely unless you connect it to the pump end to end. If you install this priming pot say 16" or 24" upstream on the suction side of the pump, this pot will be like a humpty dumpty unless you fabricate some custom support for it.

(2) the priming pot cover has a unique design. Unlike my pool pump that needs a special wrench to unwind it, this one has two handles that can be opened by hand without a tool. Down side is there is a clear lid and there is a retainer to open and close. Half the time the retainer picks up the lid, the other times the lid falls off the retainer.

(3) On one side of the pump there is an electrical box where the cord comes out of. The wiring instructions, the motor specs, and the priming pot drain plug are all on that side. In my case, the pipes are coming from the left, so I really need to turn the pump around for it to work, which means all these will end up facing the wall, and if I ever need to open or access these, it will be kind of awkward and inconvenient.

I noticed on the motor housing there is a sticker that says "ROTATION" with a down arrow. Anyone know what this is for? Is there some way the motor can be rotated on it's axis to spin the electrical box to face up for access if needed? I doubt it but thought I ask what the ROTATION means.

Yes, I am aware I can disconnect the pump at the inlet and outlet and turn it around for service. I just thought I mention this because it never occurred to me to ask if there is a right or left drain plug on the priming pot for cases like mine when the plug faces a wall. Oh well.

(3) Trying to figure out how to make the connections. Here is a top view of the pipes and the pump after I turned it around.

The suction side is simple. I just need to cut the vertical pipe, put in a 90 elbow and connect to the inlet union, as shown in the red line below.

The return side is a bit of a challenge since the outlet is not in the middle and my return line is also offset. Normally I would just run it across, but I need to do it in a way to not interfere with the opening and closing of the priming pot lid, my thinking is I need to cut the return horizontal pipe so I can rotate that pipe towards the wall at an angle, then a 90 elbow to turn horizontal to run it along the wall, then a 3 way valve so I can open one port to drain the pond, then a short run to directly above the outlet, then finally vertically down to a union to connect the outlet port, as shown in blue below.

Certainly more 90 elbows then ideal, but will this work?

 

[GBBUDD]

(2) the priming pot does not have a flat bottom so it's not going to sit nicely unless you connect it to the pump end to end. If you install this priming pot say 16" or 24" upstream on the suction side of the pump, this pot will be like a humpty dumpty unless you fabricate some custom support for it.

just pack a little concrete around it . but once it's dry place some rubber liner or washers between the pot and the concrete so there'
no vibration noise and make sure water can't build up in the concrete cup/ last thing you need is to give ice a place to build.

2) the priming pot cover has a unique design. Unlike my pool pump that needs a special wrench to unwind it, this one has two handles that can be opened by hand without a tool. Down side is there is a clear lid and there is a retainer to open and close. Half the time the retainer picks up the lid, the other times the lid falls off the retainer. once water is in the pot and under suction the clear will not just come off it will be stuck and ill need a little effort to remove it.

(3) On one side of the pump there is an electrical box where the cord comes out of. The wiring instructions, the motor specs, and the priming pot drain plug are all on that side. In my case, the pipes are coming from the left, so I really need to turn the pump around for it to work, which means all these will end up facing the wall, and if I ever need to open or access these, it will be kind of awkward and inconvenient.

YOU HAVE UNIONS and you need to put one onto the return line and if you did need to service those you can have access by removing the pump but you will not have the need.
I would also spin the pump Pumps do not draw water well. the PUSH water so the line in should be a straight to the motor as possible.
then from the out feed you can use street 90's that reduce head loss.

I noticed on the motor housing there is a sticker that says "ROTATION" with a down arrow. Anyone know what this is for? Is there some way the motor can be rotated on it's axis to spin the electrical box to face up for access if needed? I doubt it but thought I ask what the ROTATION means.

Rotation is of the gray housing so the outfeed is not discharging straight up but could come out to a side

The suction side is simple. I just need to cut the vertical pipe, put in a 90 elbow and connect to the inlet union, as shown in the red line below.

LOKKS LIKE THE INLET to the priming pot is a 3" don't you need a reducer?

Certainly more 90 elbows then ideal, but will this work?

More than i would ever construct i would use 45 and 22.5

 

[miamicuse]

@GBBUDD thanks might put a bit of stucco around the base of the priming pot to help steady it a bit. Not worried about ice as I am in south Florida.

I am planning on unions on the inlet and outlet so I can disconnect the pump to service it if necessary. But the drain plug being on the bottom of the priming pot facing the wall is not a good design IMO. It will be difficult to remove that drain plug and it's an overkill to disconnect the pump in order to get to the drain plug.

The inlet to the priming pot is a dual threaded connection. You can put in a 2" male adapter or a larger (may be 2.5" or 3") female adapter. However, it comes with a "half union" adapter that the union nut threads onto the outside thread and seals with a gasket (compression), and the other side of that is a 2" hub. So I need to cement a 2X1.5 bushing to it before connecting to my 1.5" pipe.

 

[miamicuse]

OK I have no idea what's going on but it's not working.

I got everything hooked up, filled the priming pot with water, closed and tightened the lit, plugged in the pump and it started running but it will not prime. It just runs and runs but the priming pot level went down to only 30%, water enters from the suction side but I can see water entering the priming pot on the suction side but the water is only 25% full of the pipe (if that). I waited a good 15 minutes and no difference.

So I think the issues can be:

(1) there is an leak on the suction side.
(2) there is a leak on the return side.
(3) the pump is defective.
(4) the pump is not powerful enough for my configuration.

I think I can rule out #2 because I hooked up a garden hose to the return side to test for leaks with my water supply so it should be OK. I could not do the same for the suction side because there is a check valve that would prevent continuous flow through the entire run.

On the suction side 90% of the pipe run is exposed because they were freshly laid and I haven't backfill the trench yet. I touched every joint I saw no moisture but since it's on the suction side it may not exhibit any moisture only air drawn inward. But I am pretty good with plumbing and primed/cement every joint and waited at least 12 hours for cement to cure before pressurizing.

May be the pump is not powerful enough? It is the 3600GPH model, has a 12' max head. My intake pipe is a 25' run from pond to pump, and 25' from pump back to pond. So using the 1' of head loss per 10' run that's 5' of head loss. The intake is 36" below grade, and the pump is 8" above grade, a total of 42" of lift to get to the pond, so that's another 4' there. Total 9' of head needed. Now if I am pushing a waterfall 5' high, that will be 14' of head needed and that would exceed the 12' max head right? But in this case, I disconnected the water feature and let the pipe run back into the pond at grade as a test, and still it is not priming and flow is very low.

I do have a number of pressure 90 elbows that may contribute to some cavitation, but I do not think this will make or break the operation. May be I just need more power? This pump is 1/8HP and my tiny utility pump is 1/4HP.

 

[miamicuse]

I made a sketch of the pipe configuration to show locations of key components and some dimensions. The entire run is about 34' long. There are some up and down and back up of the vertical profile in order for the pipe to go over the pond's concrete edge then back down for the line to be buried below grade. From the intake point at the pond to the priming basket there is a vertical distance of over 3 feet.

Here is an overall profile, suction line in blue, return line in red:

profile near the pump area:

profile near the pond edge & check valve:

an actual picture of the pipes at the check valve.

Will leaving it running for say an hour be advisable?

I wonder if I need a bigger more powerful pump.

 

[GBBUDD]

Ok this is where your either going to love me or hate me.

The first photo your adding so much head on your pump. Look at it like this your in a car doing 50 miles an hour and your getting off the highway and there is the standard ramp where it rounds up to another highways but you can keep your speed. Now take the same speed and try to do that as you turn into a on lane side street that's at a 90 degree. Not easy to next to impossible. well you have kida done the second to your self it will work but the water is hitting a wall head on them being pushed to the side at the same time more water is coming from behind.
That three way valve is best where water comes in from the right where you have the plumbing capped. Allow the water to flow down the wall and straight through the valve and have the inlet to the valve where the pump enters now be for the back wash.

You also installed a 90 at the top of the pump which is not horrible but it too pushes the water to that 90 degree side street the water gets slowed down just a little to make the corner. They do sell street 90's yes that's the name but its not a hard 90 inside it has rounded corner not hard corners per say.

The crucial height your not giving us in from the center of the intake to the priming pot to the water level.
The other issue is the distance your pipe is running it is full of air and has way more air then you have volume of water in the priming pot. external pumps do not pull water very well And they are even worse at pulling air " they don't "

You could cut in a water spigot as close to the check valve as possible. " garden hose connection" You get a 2 inch with a threaded reducer usually a female 3/4" where you screw in a spigot . Then you need a double female hose adapter to one end screws onto the spigot just like a garden hose would then you do screw a connected garden hose to your house and the new adapter . turn the water on and let it fill up the pipe. water should push the air out of the pipe and fill your priming pot when that starts to happen shut he water off close the valve to the spigot. turn on your pump. It should fire up first shot.

The other option is to try and keep filling the priming pot up to the lid water should back flow toward the check valve you need to fill the pipe with water .

If you have like 2 or 3 feet from water level to the pumps intake option 1 may not even work but is your best bet you can leave the water on while you start the pump giving you extra push toward the pump

i tried to do similar with a 12000 pump where it was pulling from 5 feet below and it failed no matter what i did . a submersible pump was needed but hey have terrible head pressures

 

[GBBUDD]

 

[miamicuse]

Ok this is where your either going to love me or hate me.

The first photo your adding so much head on your pump. Look at it like this your in a car doing 50 miles an hour and your getting off the highway and there is the standard ramp where it rounds up to another highways but you can keep your speed. Now take the same speed and try to do that as you turn into a on lane side street that's at a 90 degree. Not easy to next to impossible. well you have kida done the second to your self it will work but the water is hitting a wall head on them being pushed to the side at the same time more water is coming from behind.
That three way valve is best where water comes in from the right where you have the plumbing capped. Allow the water to flow down the wall and straight through the valve and have the inlet to the valve where the pump enters now be for the back wash.

You also installed a 90 at the top of the pump which is not horrible but it too pushes the water to that 90 degree side street the water gets slowed down just a little to make the corner. They do sell street 90's yes that's the name but its not a hard 90 inside it has rounded corner not hard corners per say.

The crucial height your not giving us in from the center of the intake to the priming pot to the water level.
The other issue is the distance your pipe is running it is full of air and has way more air then you have volume of water in the priming pot. external pumps do not pull water very well And they are even worse at pulling air " they don't "

You could cut in a water spigot as close to the check valve as possible. " garden hose connection" You get a 2 inch with a threaded reducer usually a female 3/4" where you screw in a spigot . Then you need a double female hose adapter to one end screws onto the spigot just like a garden hose would then you do screw a connected garden hose to your house and the new adapter . turn the water on and let it fill up the pipe. water should push the air out of the pipe and fill your priming pot when that starts to happen shut he water off close the valve to the spigot. turn on your pump. It should fire up first shot.

The other option is to try and keep filling the priming pot up to the lid water should back flow toward the check valve you need to fill the pipe with water .

If you have like 2 or 3 feet from water level to the pumps intake option 1 may not even work but is your best bet you can leave the water on while you start the pump giving you extra push toward the pump

i tried to do similar with a 12000 pump where it was pulling from 5 feet below and it failed no matter what i did . a submersible pump was needed but hey have terrible head pressures

GBBUDD, thank you.

I do have a number of those 90 elbows with a sharp angle instead of those with a curve. However that was done on purpose because I cannot find elbows designed for pressure applications with a curved transition. The ones with curved transitions are designed for drains and vents, they have a much shallower hub for the joint and I do not feel comfortable using those. I know some have used them but I am still skeptical. If you know of a source for 90 elbows with curved transition that are designed for pressure applications let me know.

I spoke to a technical support rep at MDM pump (manufacturer of Sequence pumps) and after reviewing my configuration he thinks the 750 should work but he believes my issue is positioning the check valve too high. I placed it out of the pond where the pipe goes over the pond edge then back down below grade. He suggested that I move the check valve into the pond further closer to the intake port. I might try that.

Like you said may be the way I have the pipe going up and back down is creating a section that traps air that cannot escape. I may need another opening somewhere to allow priming of that to drive out the air pocket.

 

[GBBUDD]

elbows designed for pressure applications with a curved transition.

a 4000 k pump doesn't come close to having enough pressure to blow a fitting yes you are correct they are generally waste line so solids don't get left behind. i run a 12000 k performance pro 6 years now no issues. But if you looked at the videos 4000k is already a minimal amount of water restrict it furtherby adding hard 90's and throwing it a wall will reduce your flow further.

 

[Pablo]

I was looking at the manual online, number 3 of the installation instructions says the check valve has to be under the water level because the pump is not self priming. So perhaps the solution offered by the manufacturer rep will help. Just curious, I thought you were going with PerformancePro, what changed your mind?

 

[miamicuse]

a 4000 k pump doesn't come close to having enough pressure to blow a fitting yes you are correct they are generally waste line so solids don't get left behind. i run a 12000 k performance pro 6 years now no issues. But if you looked at the videos 4000k is already a minimal amount of water restrict it furtherby adding hard 90's and throwing it a wall will reduce your flow further.

I understand these pressure fittings with a sharp 90 turn will have energy loss and may cause some cavitation, but I am still skeptical of using gravity drain fittings because when I plumb these lines, I plumbed them without making any decision on the specs of the pump I end up using. I ended up getting this 1/8HP Sequence pump with a 12' head (which may turn out to be a mistake) or I could have ended up with a 2HP pump with a 50' head. I do not want the connections to be a weak point, the same reason I stay away from Fernco couplings even though I know many people use them without problems and could have made my life easier.

Secondly, I tested the line before I even got the pump, I made a garden hose adapter X 1-1/2" spigot and fed the return line with city water. The city water at 50PSI, went through the 30' of pipe with these sharp 90 elbows going down and up and back down and finally pushed water out of the water feature 6' above the pond water level with no issue whatsoever. I thought this pump could do better than city water pressure.

Today, I took part of the intake line apart, I wanted to take a look at the check valve. To my surprise, the check valve (as far as I know been there since 1992 original pond install) is full of mud. Not only it's full of mud, it took quite a bit of strength to push that spring open, and when I did push it open I don't think it was opening enough to let 1-1/2" of volume through. Could this be the reason the pump is not performing? The check valve is stuck and packed with mud?

Is this the right kind of check valve? The spring is quite strong but it doesn't open "full port". I think if leaves, twigs, seeds can easily jam and cause it not to close fully and I wonder if the 1/8HP pump can pull the spring open.

 

[miamicuse]

I was looking at the manual online, number 3 of the installation instructions says the check valve has to be under the water level because the pump is not self priming. So perhaps the solution offered by the manufacturer rep will help. Just curious, I thought you were going with PerformancePro, what changed your mind?

The smallest PerformancePro is 1/8HP same as the Sequence 750 3600GPH, I was comparing the specs between the two and could have gone with either one. The Sequence with the priming pot is $200 cheaper but that may have been a mistake because I had never had to struggle so much to get a pump primed and running. I am hoping that the spring loaded check valve with packed dirt was the culprit.

 

[Pablo]

The smallest PerformancePro is 1/8HP same as the Sequence 750 3600GPH, I was comparing the specs between the two and could have gone with either one. The Sequence with the priming pot is $200 cheaper but that may have been a mistake because I had never had to struggle so much to get a pump primed and running. I am hoping that the spring loaded check valve with packed dirt was the culprit.

That check valve probably is at least part of the problem. Pretty sure using a spring check valve is a no-no, swing check valves are the preferred type of valve. Plus the valve is thirty years old so a new one is in order anyway so just go with a swing.
Forgot to mention I love how you do your diagrams on here, very clear.

 

[miamicuse]

That check valve probably is at least part of the problem. Pretty sure using a spring check valve is a no-no, swing check valves are the preferred type of valve. Plus the valve is thirty years old so a new one is in order anyway so just go with a swing.
Forgot to mention I love how you do your diagrams on here, very clear.

Thanks!

The check valve is definitely part of the problem, I did a bit more testing today, and I am now considering a different pump. I will summarize what I did in the next post.

 

[miamicuse]

OK, I think I am admitting defeat with this pump. I just don't think it's powerful enough for my pipe configuration.

Yes, I have a long stretch of horizontal run, a 33' run from pond to pump, and another 30' from pump back to pond, a total of 60' PVC. That will cause some energy loss.

I also have a number of 90 elbows. The pipe needs to come up to go above the pond's concrete edge, then back down into a trench to be buried under a walking path. This inverted U may be a challenge to prime with trapped air. Many elbows also contribute to more energy loss.

The spring loaded check valve packed with mud has been removed.

What I did I hooked up a submersible utility pump (1/4HP Everbilt) to take water from the bottom of the pond, then run a 30' garden hose from that pump into the 1-1/2" intake line, using a hose adapter X 1-1/2". I turned the utility pump on (with the pond pump OFF), and that small utility pump pushed out all the air in the pipe and after a minute or so no more bubbles and water is coming out of the return line strong. I then switched a few ball valves and redirected the return line to a line to go to a water feature that is 5' above grade and the that worked fine also.

Once I have everything working and the line full of water, I turned the pond pump on, and disconnected the garden hose feed from the utility pump. Immediately the water inside the priming pot dropped and feeling my hand on the intake and return lines I felt no suction on the inlet and no positive pressure on the outlet. It just can't seem to keep prime or keep the water moving, or both.

I did another check on all the joints and didn't see any leak in the lines.

I think the fact that the 1/4HP utility pump when connected to the suction inlet, is able to pushed the water all the way, up through 30' of coiled 5/8" garden hose, back down into the suction inlet, through 33' of pipe into the pump then back out of the pump another 30' of return with all the hard 90 elbows then go up to the water feature without any problem, means I need a more powerful pump then the 1/8HP Sequence 750, correct?