I've done something very wrong with my closed loop it seems.

[CHUBAKAH]

Thanks in advance for taking a look.

 

I

[shawns]

i hope you opened your valves that you plumbed. they appear to be closed in the pictures.

[CHUBAKAH]

i hope you opened your valves that you plumbed. they appear to be closed in the pictures.

 

I knew someone was going to pick up on that. Yes they were open at testing. I was about to pull it all apart and check for some kind of blockage is why they are off now.

 

I then figured I would come upstairs and start a thread to see if someone saw something way off before I did.

[traveller7]

Wow, that is one heck of alot of head loss from plumbing alone. Have run run the fittings and pipe against a calculator? Ran a quick estimate and head loss(input and output) looks like it is over 25' and it appears you are running the following pump:

100PX-X 1270gph 13' 130W 1" MPT / 1" MPT 10.5"x4"x5.5" 40RLXT

 

Is that correct?

 

edit: fwiw this is the calculator I was using:

http://reefcentral.com/calc/hlc2.php

Edited March 18, 2008 by traveller7

[CHUBAKAH]

Wow, that is one heck of alot of head loss from plumbing alone. Have run run the fittings and pipe against a calculator? Ran a quick estimate and head loss(input and output) looks like it is over 25' and it appears you are running the following pump:

100PX-X 1270gph 13' 130W 1" MPT / 1" MPT 10.5"x4"x5.5" 40RLXT

 

Is that correct?

 

edit: fwiw this is the calculator I was using:

http://reefcentral.com/calc/hlc2.php

Yes that is the pump.

 

Any thoughts?

[flowerseller]

Looks like a lot of pressure from the weight of the water alone forcing against the plumbing.

 

Also, is that net hanging by the back leg of the stand?

If so, you might want to add atleast another 2x4 to each leg.

[CHUBAKAH]

Looks like a lot of pressure from the weight of the water alone forcing against the plumbing.

 

Also, is that net hanging by the back leg of the stand?

If so, you might want to add atleast another 2x4 to each leg.

There is another brace you can't see at the side, but that is a whole other subject. There will be some additional work to the stand, as well as the room.

 

The base of the stand is about 42 inches from the ground.

 

I'm guessing by the responses so far there isn't anything that drastically stands out?

[traveller7]

I'm guessing by the responses so far there isn't anything that drastically stands out?

Yes, drastic issues are in the design itself. Calculate the head value.

 

If I understand the plumbing depicted:

 

The plumbing design creates too much resistance. You will get low amount of flow out of each output, if any.

 

You can test the theory by closing off 3 inputs, and 3 outputs which reduces the flow through all the 1" pipe, fittings and elbows. If the total flow increases substantially, tweak by opening and closing outputs one at a time.

 

IME, you would find a substantial increase by utilizing a single larger input, and alternating the outputs to allow only a single/dual to be open at a time.

 

Of course, you can overcome plumbing issues with a more expensive power sucking heat introducing pump.

 

Best of luck.

[CHUBAKAH]

Yes, drastic issues are in the design itself. Calculate the head value.

 

If I understand the plumbing depicted:

 

The plumbing design creates too much resistance. You will get low amount of flow out of each output, if any.

 

You can test the theory by closing off 3 inputs, and 3 outputs which reduces the flow through all the 1" pipe, fittings and elbows. If the total flow increases substantially, tweak by opening and closing outputs one at a time.

 

IME, you would find a substantial increase by utilizing a single larger input, and alternating the outputs to allow only a single/dual to be open at a time.

 

Of course, you can overcome plumbing issues with a more expensive power sucking heat introducing pump.

 

Best of luck.

Thanks,

I'll have to let Sean over at Fin and Feathers know his design sucks, because I followed it to a tee.

 

More money down the drain.

[traveller7]

Thanks,

I'll have to let Sean over at Fin and Feathers know his design sucks, because I followed it to a tee.

 

More money down the drain.

You have one opinion based on a few pictures, take it with a grain of salt until proven through testing ;>)

[dandy7200]

That pump should have no problem pushing water through your plumbing as you have it. Potential gotchas: Did you remove the rubber plugs that are on the pump from the factory? I see you have a check valve (not needed for this application btw) is it orientated the correct way?

[DaveS]

So I don't get it. It thought the idea behind a closed loop system was that it is closed. Therefore water pressure would be equal on both sides of the pump (intake/output). As opposed to an open loop like most sumps and returns where there is not water pressure on the intake (other than gravity) and the pump must overcome head pressure on it own. I thought with a closed loop the intake water pressure would compensate for the head pressure on the output.

 

In other words, if you stopped the pump, all water would stop flowing immediately in a closed loop where as in an open, some water would continue to flow down to the sump.

 

What am I missing?

 

EDIT: Just saw Dan's posting after I posed. His comments about the check valve jive with my understanding. If this were open loop, I could see the desire for a check valve.

Edited March 19, 2008 by DaveS

[traveller7]

So I don't get it. It thought the idea behind a closed loop system was that it is closed. Therefore water pressure would be equal on both sides of the pump (intake/output). As opposed to an open loop like most sumps and returns where there is not water pressure on the intake (other than gravity) and the pump must overcome head pressure on it own. I thought with a closed loop the intake water pressure would compensate for the head pressure on the output.

Water pressure is the same, until you turn the pump on, then pressure is less on the intake, higher on the output. Once turned on, a pump sees

[ErikS]

There is no head loss in a closed loop only friction loss.

 

Anyone who believes differently needs to go back to school.

 

One 2X4 on end, 24 inches long, will support 19,000+ pounds before it deflects sideways enough to fail. Given what appears to be 30(ish)" it's likely closer to 15,000 pounds - I'd say safe.

[ctenophore]

I have Escobal's book if you want to borrow it. Part of the problem is that 1270gph is wide open, zero head pressure. Let's say you have ~10ft head pressure (I think 25ft is too high). Not having the flow curve in front of me, I'm going to guess about 800gph at 10ft for that pump. You have very little head pressure in your manifold, since all the pressure is in the intake and the section of output up to the manifold. Those sections of pipe are carrying 800gph. Your manifold then divides that flow rate by 4. So you're looking at ~200gph through each 1" opening; slightly more in the center and less on the far right and left (water will take the path of least resistance). So, ~200gph through a 1" opening is not going to feel that strong, especially underwater.

 

I would try an oceans motions or maybe one of those new 1" scwids, which will allow the pump to push all water through one or two outputs at a time. You'll get variable currents along with a more concentrated flow.

[davelin315]

The problem I see right off the bat is that your loop is based on one single 1" feed and then it splits into four 1" returns. When you consider how much water flow you are losing due to friction combined with dividing the flow between 4 different returns, you get very little flow. Add onto that that the water will go the path of least resistance, you will most likely end up with little or no flow through the top two returns. Even if you had the pump running full throttle through one return with a T on it so that there was a side return, you'd still get very little flow through that. I would bet that your flow is all going through the bottom two returns and is only trickling through the top two. I think that you would add a bit more flow by simply capping off some of the returns (or at least even it out to 3 feeds and 3 returns) and then increase the size of the plumbing on the return and feed. You can only force so much water through 1" pipe and then when you divide that flow, it's going to decrease the velocity which makes it seem like there's less flow. If you have a larger pipe at the start and then decrease it at the end, you'll increase velocity without losing as much flow due to friction (head pressure).

[Origami]

One 2X4 on end, 24 inches long, will support 19,000+ pounds before it deflects sideways enough to fail. Given what appears to be 30(ish)" it's likely closer to 15,000 pounds - I'd say safe.

 

Correct me if I'm wrong here, Erik, but the point of failure of the 2x4 is not the same as the point where the system fails. The threshold of system failure would be when the 2x4's deflect enough to cause the tank to fail (break). The tank would fail due to small deflections far earlier than the 2x4's themselves (in which case the 2x4 would never really break, would it?).

 

Here's the link to the curve for your pump: http://www.panworldamericas.com/PX/60Hz/A3400468.pdf.

 

It looks like with 10' of loss (due mostly to twists & turns, with no allowance for vertical lift since this is closed loop), you're looking at about 507 gph out. That's about 125 gph from each outlet if equally divided.

Edited March 19, 2008 by Origami2547

[ErikS]

Correct me if I'm wrong here, Erik, but the point of failure of the 2x4 is not the same as the point where the system fails. The threshold of system failure would be when the 2x4's deflect enough to cause the tank to fail (break). The tank would fail due to small deflections far earlier than the 2x4's themselves (in which case the 2x4 would never really break, would it?).

Correct..........but then we'd have to get details like when the deflection becomes critical

 

Reality is that it would fail with some 15,000 pounds of load - even with a 500 gallon tank completely resting on a single 2x4 your not even 1/3rd of the way to it's load capacity.

 

On topic davelin315's got it right, lot's of friction loss (I forget the friction coefficient of 1" sch 40, but it's a bit) & 4 outlets = low output.

[traveller7]

Don't forget the loss on the intake side, in this case it appears substantial as well. If you can't feed the pump, why would you expect anything to come out the other side?

 

Intake strainers, elbows, valves, input count, 1" pipe, etc., all negatively impact this design on the intake side.

There is no head loss in a closed loop only friction loss.

 

Anyone who believes differently needs to go back to school.

I'll save you the trouble of signing up for the class:

 

What is Pump Head?

 

Units of Measure: In the U.S. system, head is measured either in PSI or in "feet of head" (usually abbreviated to "feet").

 

Pump Head is the total resistance that a pump must overcome. It consists of the following components:

 

Static Head: Static head represents the net change in height, in feet, that the pump must overcome. It applies only in open systems. Note that in a closed loop system, the static head is zero because the fluid on one side of the system pushes the fluid up the other side of the system, so the pump does not need to overcome any elevation.

 

Friction Head: This is also called pressure drop. When fluid flows through any system component, friction results. This causes a loss in pressure. Components causing friction include boilers, chillers, piping, heat exchangers, coils, valves, and fittings. The pump must overcome this friction. Friction head is usually expressed in units called "feet of head." A foot of friction head is equal to lifting the fluid one foot of static height.

 

Pressure Head: When liquid is pumped from a vessel at one pressure to a vessel at another pressure, pressure head exists. Common applications include condensate pumps and boiler feed pumps. Condensate pumps often deliver water from an atmospheric receiver to a deaerator operating at 5 PSIG, meaning that in addition to the other heads, the pump must overcome a pressure head of 5 PSIG. One PSIG equals 2.31 feet, so the differential head in this application is 5 X 2.31 = 11.6.

[flowerseller]

I was thinking more of if the back of the tank got bumped it will likely come down.

There's little side to side help in that event.

You'd never catch me under that stand.

 

Then again, with that much plumbing, it might have enough to prevent it from swaying, still.....

[CHUBAKAH]

It seems there is some confusion as to how this is exactly set up. That's partly my fault for not adding any side view pictures.

 

There are four returns from one 1" line, however they are all at the front side of the tank in the bottom. Those are the four you see in pic 2 with unions all connected.

 

The two bulkheads you see in pic 1 and 2 at the bottom back of the tank backside, are the overflows back to the pump. Pic three shows the front of the tank with the four , we'll call them jets. They are approx 3" off the bottom of the base of the tank. The two returns in the back of the tank are approx 4" off the base of the tank.

In other words all 6 bulkheads are with in 1" of each other in height.

 

Outside of the one at the far right in the pic, all of the resistance should be exactly the same, and TBH that is pretty much what I have. I'm sure if I was to remove the additional piece I added in to drain the tank at the far right, and got rid of the tee and changed it to a 90, all four returns would be the same flow.

 

The top two bulkheads that are seen in the pictures come together, and veer of to the left are the returns that go back to my 100 gallon sump, not seen in the pictures, and there IS NOT a ball valve on that line, to end that confusion as well.

 

I also have no problems with my sump exhaust and returns, just this closed loop system. All of that seems to be A OK.

 

As far as the stand, It could never move side to side because at the base of the tank, or top of the stand has a 3/4" piece of plywood screwed and glued every 6". I also have angled braces at the sides not shown in the pictures which I already mentioned in another reply.

 

For the guy who would not stand near my stand, I challenge you to come by and try and move it. I've mentioned before I am a general contractor. You guys who do the DIY stands crack me up. The floors in your homes don't have 1/10th the bracing your tank stands do.

 

From all of the posts I have read here, and another board I think I just need to change the right side to match the left, and replace my pump with something stronger.

 

The question is, how much stronger?

 

I am planning to have mostly softies, but I also want to add in a few of everything at some point, but that's a new thread for you guys.

[traveller7]

The question is, how much stronger?

The first question is actually, "What is the target flow?"

Then calculate system head.

Then choose pump which meets the target flow.

 

fwiw: If you can't tell, I think your pump is fine. Spend $ on the pvc and possibly add an oceans motion, sqwd, etc.

[CHUBAKAH]

The first question is actually, "What is the target flow?"

Then calculate system head.

Then choose pump which meets the target flow.

 

fwiw: If you can't tell, I think your pump is fine. Spend $ on the pvc and possibly add an oceans motion, sqwd, etc.

That's just it though. I have no idea what my target flow is supposed to be, or have any idea. I just knew from the get what I have isn't much at all.

[traveller7]

That's just it though. I have no idea what my target flow is supposed to be, or have any idea. I just knew from the get what I have isn't much at all.

Have you tried to close off all but one return? A cap on all but one in the tank should do it.

 

If that is "enough" flow, it is possible a flow alternating device will be sufficient. Fine tuning the return line during that stage should give you a drastic improvement as well.

[CHUBAKAH]

Have you tried to close off all but one return? A cap on all but one in the tank should do it.

 

If that is "enough" flow, it is possible a flow alternating device will be sufficient. Fine tuning the return line during that stage should give you a drastic improvement as well.

Yes, and the flow is dramatically increased, but you already knew that.

 

I was considering This device to cure the problem, but it looks as though thats going to give me the option to have two lines of two heads each.

 

I'm sure it will be better than what I have now, but my question remains how much flow do I really need to be successful?

 

Is there some kind of rate I am looking to accomplish?