Moving Iwaki to other side of wall

[jharding08]

I bought a Japanese built Iwaki MD-40RXt for my 120 gallon reef to move more water through my 40 gallon sump as well as power 3 TLF150 media reactors.

When I first hooked it up I noticed it was much louder than my previous submersible pump.



I did some research and tried removing the fan shroud and fan temporarily to see if that would quiet it down. I noticed a minimal change in noise, so it must just be how loud the motor housing is. I downloaded a decibel meter app for my phone, so I'll see if its unusually loud.

I don't think it is unbearable, but if I could find a way to get it as quiet as possible, it would be a more pleasurable experience when we are in the same room as the tank

My only other option is to enclose the pump in a box of some kind. I can't put a box around it because there will be no where for the heat to go. I could enclose the stand where the sump is installed, but there would also be no where for the heat to go and it will heat up the sump/water



My only other option is to relocate the pump and run some longer PVC. Its overpowered right now, so some head loss is ok. I was thinking...the garage is on the other side of the wall that the tank sits up against. I rent my house, but repairing a couple of 1.5" holes shouldn't be a big deal, and the garage is just unpainted dry wall. I figure 3 holes, 1 for inlet, 1 for outlet, 1 for plug, since I still want to control it with the Apex.

I figure I could just extend the inlet line from the sump, and this would even allow for a straight connection into the Iwaki without an elbow so close. The outlet might be more difficult to not have too many 90s close to the outlet, but I could reconfigure to allow for the gate valve and a T off to the reactors.

Has anyone else run to another room horizontally? I know a lot of people have their sumps/pumps in the basement and pump up 10-15 ft to the tank. I'm not going to put the sump in the garage, just the pump.

 

[AcroporAddict]

For all the trouble, how about just do another submersible instead? Heat problems? All external pumps will be louder to some extent than a submersible. But, you also have the option of running some submersibles externally. Mag Drives and eheims can be run externally as well. Just some ideas instead of putting holes in your walls.

IME Pan World pumps are less loud than Iwakis, but not dead silent either. I run an Iwaki 70 as the return on my 465 gallon tank, and it is not quiet, but the equipment is in an unfinished part of the basement, so noise is not a factor in my case.

 

[jharding08]

When I designed my sump, I opted for more room in the skimmer and refugium chambers since I knew I was going to have an external pump. my return chamber is only 3.75" wide, not a lot of high powered submersibles fit in that space.

Are Mag Drive and Eheims quieter than Iwakis when run externally? I have a Mag 12 I bought a while ago, but it didnt get good feedback

 

[AcroporAddict]

Are Mag Drive and Eheims quieter than Iwakis when run externally? I have a Mag 12 I bought a while ago, but it didnt get good feedback

I have not run one externally, but I would guess they would be. I have a sulfur denitrator with an external Eheim recirculation pump on the top of it, and I would never know it was running if I didn't touch it and feel it humming.

It would be pretty easy to test it out with a 5 gallon bucket of water and a couple lengths of vinyl tubing on the intake and output, though.

 

[jharding08]

I am leaning towards just drilling a couple holes in the wall and running 1" PVC for my Iwaki mounted in the garage. There is just two sheets of drywall and nothing in the wall.

This way I can mount my three TLF150s in the area in the stand where the Iwaki was before.

I can do a right angle out of the sump like i currently have and run it straight into the garage and straight into the inlet of the pump.

For the output I need to get the plumbing running horizontal within 3 feet of height to make sure it can terminate in the stand.

I assume bends are better in the output rather than input near the pump. Should I use flex tube instead? Like run the PVC just on the other side of the garage wall, and then use flex tube to connect to the Iwaki? Trying to avoid cavitation

 

[uncleof6]

If you are going that far, increase the intake plumbing size to 1.5", don't waste the pumps power on dragging water through that length of pipe, and the resulting cavitation. Flex is not really the solution, just a large pipe and 10x the pipe diameter between any direction change (flex or other wise.)Yes it makes a large difference, in terms of pump performance.

On the noise, I don't consider mag-drives and eheims appropriate for our applications (especially over 50 - 60 gallons) so I will leave them alone. On the Iwakis, they are very much inline with all small 2-pole motors. With the rpms up ~ 3200 rpm, the fan is going to make a whine, no matter what. I have seen them with the fan removed, and replaced with things as odd as computer fans. Well, a lot of things work, most don't work so good.

You can't run the pump without the fan, so your options are limited. Best bet would be to get your hands on a smaller 4-pole motor such as used on the snapper/darts etc. Can't hear them at all (~1600 rpm.) No, they would not be too big for a 120. I have done 120s with darts...

 

[jharding08]

If you are going that far, increase the intake plumbing size to 1.5", don't waste the pumps power on dragging water through that length of pipe, and the resulting cavitation. Flex is not really the solution, just a large pipe and 10x the pipe diameter between any direction change (flex or other wise.)Yes it makes a large difference, in terms of pump performance.

On the noise, I don't consider mag-drives and eheims appropriate for our applications (especially over 50 - 60 gallons) so I will leave them alone. On the Iwakis, they are very much inline with all small 2-pole motors. With the rpms up ~ 3200 rpm, the fan is going to make a whine, no matter what. I have seen them with the fan removed, and replaced with things as odd as computer fans. Well, a lot of things work, most don't work so good.

You can't run the pump without the fan, so your options are limited. Best bet would be to get your hands on a smaller 4-pole motor such as used on the snapper/darts etc. Can't hear them at all (~1600 rpm.) No, they would not be too big for a 120. I have done 120s with darts...

Thank you for your information. If I stick with the Iwaki, then I will keep the stock fan or do the computer fan mod. Do I just need to do 1.5" on the intake or output as well? I have a 1" bulkhead in the sump, should I put the 1"-1.5" adapter right after that and then downsize right before the intake on the Iwaki? Should I orient the iwaki so the intake is straight and the output is at a 90 to get it back to the stand?

Also, can I get more clarification on what you mean when you say "just a large pipe and 10x the pipe diameter between any direction change "
Does that have to do with the 90 bend to get back to the stand?

When I look for Reeflo pumps, I see Dart/Snapper Hybrid Pump (3600/2600 gph). Is this the only Dart out there?

 

[uncleof6]

Thank you for your information. If I stick with the Iwaki, then I will keep the stock fan or do the computer fan mod. Do I just need to do 1.5" on the intake or output as well? I have a 1" bulkhead in the sump, should I put the 1"-1.5" adapter right after that and then downsize right before the intake on the Iwaki? Should I orient the iwaki so the intake is straight and the output is at a 90 to get it back to the stand?

Only applies to the intake side of the pump. For better performance upsize the return line to 1.25" or 1.5" at the pump. Conventional wisdom is to upsize the outlet pipe 1 size up from the actual outlet size, unless it will be larger than the actual pump inlet. Forget the 1" bulkhead: run the return up over the back. 1" is too small for that tank and that pump (the iwaki.)

Also, can I get more clarification on what you mean when you say "just a large pipe and 10x the pipe diameter between any direction change "
Does that have to do with the 90 bend to get back to the stand?

The 10x rule applies to the pump intake side. 10x the pipe diamter straight run between the last direction change and the inlet to the pump volute. (e.g. don't put an elbow/direction change within 15" of the volute inlet.

When I look for Reeflo pumps, I see Dart/Snapper Hybrid Pump (3600/2600 gph). Is this the only Dart out there?

That is the only Dart that I am aware of.

 

[jharding08]

Are you talking about bypassing the 1" bulkhead going from the sump to the pump intake?

My whole tank is plumbed with 1" bulkheads, on the return in the sump and the siphon, open channel and emergency channel for the overflow. I was planning on pushing around 1000 gph through the system and was under the impression that 1" would be fine. Plus the intake and output on the Iwaki is 1". I know bigger is better, but until I redo my tank design, I am stuck with the 1" bulkheads.

What would be the best way to plumb my iwaki with the current plumbing. I know it might not be the most efficient, but until I get a new tank, its what I am stuck with.

Thank you for your help and patience

 

[uncleof6]

Are you talking about bypassing the 1" bulkhead going from the sump to the pump intake?

My whole tank is plumbed with 1" bulkheads, on the return in the sump and the siphon, open channel and emergency channel for the overflow. I was planning on pushing around 1000 gph through the system and was under the impression that 1" would be fine. Plus the intake and output on the Iwaki is 1". I know bigger is better, but until I redo my tank design, I am stuck with the 1" bulkheads.

What would be the best way to plumb my iwaki with the current plumbing. I know it might not be the most efficient, but until I get a new tank, its what I am stuck with.

Thank you for your help and patience

Point blank, with the present configuration w/o modifications in pipe sizes etc: It isn't so broken, so don't fix it. when you are done "fixing" it for noise, it will be more broken flow wise. You already are not using the pump at its capability, in that your pipe size is too small.

As for your impression of the pipe size:

Reeflo, is the only supplier, supplying pumps to the hobby, that gives facts concerning pump installation...this applies to all centrifugal pumps; for submersible pumps it applies to the outlet only, and for mag-drives, it does not apply: the mag-drives are unique junk (9.5 and larger) requiring 1.5" oulet pipe.)

"The size of the pump’s suction and discharge ports does not indicate your proper pipe size." What does determine the size of the pipe is the installation, flow rate desired, and pump capability. As much as the importance of proper pump installation, gets minimized, it is still an engineering problem complete with some relatively simple mathematics.

"Locate the pump as close to the source as possible. The pump (all centrifugal pumps) are designed to push water not pull it."

Flow rates for pipe size: (pump systems; is not related to drain lines in any way. Well...it is, but not applied in this manner)

1" 600 gph
1.25" 1200 gph
1.5" 1800 gph

Exceeding these values, and you lose pump performance due to excessive friction losses, you waste electricity, and you need a larger pump to do the same job, which is a further waste of electricity. Notice that the function to derive these particular values is linear (rather than a curve,) which makes it very easy to predict. (2" 2400 gph, etc.)

Your target flow rate is 1000 gph. Your pipe size is 1". So your friction loss is already excessive, making it rather unlikely that you will achieve that 1000 gph (depends on the actual pump curve, reality wise, not the idealized published flow curves.) A pipe size increase to 1.25", will reduce the friction loss by ~2/3. In many cases, you can use a smaller pump to hit the target flow rate. Going the opposite direction, in most cases, you need a larger pump to hit the target flow rate. Again, it depends on the pump curve.

This can be easily demonstrated, by comparing a bar straw, with a regular straw. (1" pipe is the bar straw, 1.25" pipe is the regular straw.) Get a mickey D's chocolate shake, and drink it through the bar straw, for a bit. Then switch to the regular straw. Note the difference between the energy required to drink through the bar straw compared to the regular straw. This is the way it is with centrifugal pumps.

You want to increase the distance from the "source" to the pump inlet, using the bar straw...are you getting the idea here? Bad idea... I won't do the demo for pushing through the straws...............but it is the same concept.

All things considered, without increasing the pipe size (on both the inlet and outlet side,) you would "theoretically need" a larger pump to do the same job. The problem is, you can't simply move the pump, there is more involved, since it is already pushing/pulling against excessive friction loss.

This system already under-plumbed, and should be using 1.25" pipe. Hence if the distance to the pump increases, 1.25" pipe is the absolute minimum that should consider as being practical. That is stem to stern, including the bulkheads. Only by actually doing the math, will you know if 1.25" will deliver the 1000 gph you are after, with the particular pump inhand.

Calculate the actual friction losses in the pipe, based on fittings, inside diameter, lengths of pipe, etc @ 1000gph, convert the value to vertical lift. This is done for both the intake and outlet side of the pump, they add together and are added to the static vertical lift. This gives the total (close enough) dynamic head. That figure is what gets compared to the pumps flow curve. Yes, this is necessary for "our purposes."

Some have suggested replacing the pump, at this point that is probably a better solution, yet there will still be the same problem with the pipe size, as it is the one thing all centrifugal pumps have in common.

NOTE: I did mention the pc fan modification, it works, but it don't work that good, and will probably result in replacing the pump due to heat damage.

 

[jharding08]

Could I keep my 1" bulkheads, but replumb with 1.25 or 1.5" plumbing to the pump as well as to the return nozzles? Would i need to change my drain size as well? from 1"?

 

[jharding08]

Also, is 24" too far away from the source?

 

[dcmartinpc]

Moving Iwaki to other side of wall

I run an iwaki md100rlt 3 feet away from the source fed with 1.5" flex PVC and 1" flex on the outlet feeding 2 tanks on my main level from the basement with 20 lateral feet and 14 vertical feet in each run with zero issues. Yes it does induce more friction loss, but, in a larger pipe, you are pushing against a heavier water column and you are losing power there also. The 100 still moves a TON of water with 1" plumbing.

When iwaki is quoting head loss numbers, my understanding is that they are using 1" pipe as a reference, so the friction loss of a straight vertical rigid pipe is already accounted for.

I would however recommend a larger bulkhead in your sump on the drain side if you are going to move it farther away to prevent cavitation, but I think you are perfectly fine with 1" on the outlet. I recommend installing a True Union Ball Valve on both the inlet and outlet. It makes pump maintenance and swaps SO much easier. Check out savko.com. They have great Georg Fischer valves that are a great value IMHO.

Your pump is the iwaki flow bias model, but personally, I think you will be fine. There are literally thousands of people running them with 1" on both sides and they work fine. I'm not saying 1.5" isn't better and that with 6' of head it wouldn't be the best solution, but I think it is a bit misleading saying 1" is a bad idea or won't work.

Don

 

[uncleof6]

I run an iwaki md100rlt 3 feet away from the source fed with 1.5" flex PVC and 1" flex on the outlet feeding 2 tanks on my main level from the basement with 20 lateral feet and 14 vertical feet in each run with zero issues. Yes it does induce more friction loss, but, in a larger pipe, you are pushing against a heavier water column and you are losing power there also. The 100 still moves a TON of water with 1" plumbing.

The weight of the water does not have anything to do with head loss or friction loss. Head loss deals with pressure. Friction loss deals with velocity, cross-sectional area/circumference of the water column, and internal surface properties of the pipe.

The pressure at the bottom of a 1" pipe, is indentical to the pressure at the bottom of a 10' diameter pipe of the same height, or in the ocean at the same depth. Increasing the size of the pipe does not induce a power loss.

Friction loss (converted to vertical lift) is added to the static head, and the total (dynamic head) is applied to the flow curve.

When iwaki is quoting head loss numbers, my understanding is that they are using 1" pipe as a reference, so the friction loss of a straight vertical rigid pipe is already accounted for.

The flow curves only quote static lift, they do not account for friction loss. (Dynamic Head.) It is the same for every flow curve published.

I would however recommend a larger bulkhead in your sump on the drain side if you are going to move it farther away to prevent cavitation, but I think you are perfectly fine with 1" on the outlet.

Increasing the return plumbing will decrease the dynamic head, which will increase the flow rate. It is the same for every centrifugal pump produced.

I recommend installing a True Union Ball Valve on both the inlet and outlet. It makes pump maintenance and swaps SO much easier. Check out savko.com. They have great Georg Fischer valves that are a great value IMHO.

Your pump is the iwaki flow bias model, but personally, I think you will be fine. There are literally thousands of people running them with 1" on both sides and they work fine. I'm not saying 1.5" isn't better and that with 6' of head it wouldn't be the best solution, but I think it is a bit misleading saying 1" is a bad idea or won't work.

Don

There is a disparaging difference between working, and working as it should. Thousands of people using these pumps in this or that manner, is what is misleading. The vast majority of hobbyist users do not have any idea what their pump is actually putting out, and even fewer know why. Good enough is the "hobby" standard, however working as it should is the way things should be done. There is nothing misleading about it, and I did not say it would not work.

Coventional wisdom, even in the hobby, is always upsize the outlet pipe one size over the outlet size; if the new pipe size is larger than the intake pipe, upsize the intake pipe to the same size or larger.

 

[dcmartinpc]

Maybe I misread it I learned something today. I had always been told that larger diameter pipes increased pressure, but your explanation makes sense. I always upsize on the source/inlet, but not always on my outlets, primarily because I am snaking flex pipe through my floor joists!


I just wanted to make sure the OP understood that it is ok to run the pump with 1" on the outlet, albeit at a reduced efficiency.

Thanks for the information!

Don

 

[uncleof6]

Maybe I misread it I learned something today. I had always been told that larger diameter pipes increased pressure, but your explanation makes sense. I always upsize on the source/inlet, but not always on my outlets, primarily because I am snaking flex pipe through my floor joists!


I just wanted to make sure the OP understood that it is ok to run the pump with 1" on the outlet, albeit at a reduced efficiency.

Thanks for the information!

Don

The epic example of this, is posted somewhere on this forum. Don't remember where. But it is here in DIY somewhere.

The op had a rather potent small pump, with 14' static lift, and 1" pipe. It was an iwaki knock off pump, perhaps a blueline, or the yellow one (mind cloud on it right now.) The flow curves are identical to the iwakis.

Although the flow curve said what the flow should be <don't remember="" the="" exact="" value=""> at 14' (I don't remember the value,) it was actually around 750gph. Looking at the flow curve, 750gph occurs at ~ 42' lift, just below shut off head pressure. The pump was new, so no problems with the pump. So somewhere, the head height went from 14' to 42', and it is friction loss that did it.

This is an extreme example, but it holds aboslutely true for all centrifugal pump installations. So yes, 1" pipe will work, but man...what a waste of a decent pump.

Positive discplacement pumps do not suffer this malady, and the flow "curve" is a straight vertical line. Danner mag-drives are postive discplacement pumps, however suffer badly from both static lift, and friction loss. Their flow curve is very much 'identical" to that of centrifugal pumps.

There are two types of centrifugal pumps, as you had indicated earlier, flow biased and pressure biased. Flow biased pumps are designed to deliver high volume, against low pressure; pressure biased are designed to deliver high volume against high pressure. The pump above was a pressure rated pump, a flow biased pump would have reached shut off head (flow drops suddenly to a few hundred gph) a lot sooner.

Pressure in a pump system is a little complicated, as there are three descriptors for pressure: one for the pump intake, and two for the pump outlet. Two can be manipulated, one cannot be (static.) The two that can be manipulated are easily manipulated with pipe size, and the one on the intake can also be manipulated by changing the height of the water column above the pump inlet as well. In a sump this height is usually only a few inches or so, and there are reasons to not raise it too much, but there are good reasons to raise it. (to keep the pump from running dry due to evaporation.) None of this can be considered insignificant, even in our small systems.</don't>

 

[jharding08]

Thank you both for the great information. I am learning so much. When it comes time for a tank upgrade I will definitely be referencing this thread for my pump and plumbing setup.

In the meanwhile, i 'd still like to use the Iwaki, albeit in a non-optimal setup. If I keep the 1" PVC on the output, can I run 1.25 or 1.5 on the input with adapters to the 1" bulkhead on the sump and the pumps 1" intake? Does that help with cavitation / flow at all?

Also, can I rotate the cover that has the threaded output to have it going straight vertical? Right now it is at a 45 degree angle and I see pictures of some that are straight vertical. There are about 8 screws on the cover, but don't want to rip it off unless I got confirmation you can rotate the output angle. This will eliminate one bend I need to get back to the stand.

That's all my questions for now. I appreciate everyone's help immensely

 

[uncleof6]

Thank you both for the great information. I am learning so much. When it comes time for a tank upgrade I will definitely be referencing this thread for my pump and plumbing setup.

In the meanwhile, i 'd still like to use the Iwaki, albeit in a non-optimal setup. If I keep the 1" PVC on the output, can I run 1.25 or 1.5 on the input with adapters to the 1" bulkhead on the sump and the pumps 1" intake? Does that help with cavitation / flow at all?

The 1" bulkhead can be problematic.

Also, can I rotate the cover that has the threaded output to have it going straight vertical? Right now it is at a 45 degree angle and I see pictures of some that are straight vertical. There are about 8 screws on the cover, but don't want to rip it off unless I got confirmation you can rotate the output angle. This will eliminate one bend I need to get back to the stand.

That's all my questions for now. I appreciate everyone's help immensely

Yes you can rotate the pump volute. Only way to make it work in some cases, and straight vertical is way better than using a 90 to get vertical.

 

[dcmartinpc]

Agreed. You really should upsize the bulkhead in your sump to 1.5" especially if you are going to move it. But IMHO it is worth it. Do it once and be done. Never have to worry about it again.

One other quick thing, instead of drilling another hole for the plug, why not take the plug off, snake the wire through one of the holes for the pipes, and the rewire the plug? Just a thought.

Good luck!

Don

 

[jharding08]

Agreed. You really should upsize the bulkhead in your sump to 1.5" especially if you are going to move it. But IMHO it is worth it. Do it once and be done. Never have to worry about it again.

One other quick thing, instead of drilling another hole for the plug, why not take the plug off, snake the wire through one of the holes for the pipes, and the rewire the plug? Just a thought.

Good luck!

Don

How hard is it to drill 1.5" over a 1" hole in 3/8 acrylic? I'm not moving the sump and it might be a tight fit to get a drill in there and an awkward position, but if it is worth it, I'll do it. Could I run 1.5" PVC in the tank vertically and up and over and just plug the 1" bulkhead?

I like the idea about the plug too, forgot that it didnt come with an end and I put that end on it

Yes you can rotate the pump volute. Only way to make it work in some cases, and straight vertical is way better than using a 90 to get vertical.

Any tricks I need to know on rotating the volute or just remove the screws and rotate the cap?

Thanks again guys!