New to pump systems, need advice.

[vonz33]

Hi there,

I'm looking for a pump for my application. As usual, my needs are a bit outside the box so I'm struggling finding a system that fits my needs. Here is the situation:

We have this warehouse with 3 levels. The basement is provided with a sump and water raises in there quite regularly. My goal is to use this water to supply the building for various things like toilet's flush etc... I have fitted 3x 44 gallon drums up on the catwalk on top floor and have ran a feed. The feed is a 1.5" hose and runs vertically on a roughly estimated 20m height. This is a fair bit of water weight for the pump I have to admit. Our budget is limited to $200, and our power is limited to 1000w as we are running the whole place on only a 10A circuit at this stage and any excessive power load makes all the lights to dim..

I have been advised by a "specialist" that this one

http://www.davey.com.au/site/DefaultSite/filesystem/documents/datasheets/DPM128-4_D42_53_0.pdf

would deliver 60LPM at 20m, the guy that was pretty much reading from his paper charts so not sure how to trust him. Most people that uses sump pumps do not use the water, they just dump it so no need for most these sump pump customers to run a feed up 20m high... Now on spec sheets there are some data such as HP, Wattage, Max Height etc etc... Some petrol ones are 2.5HP, has the same rating as a 6.5HP and the multi stage electrical seems more power efficient but cost a lot of bucks...

I was thinking of a petrol pump as it seems to have more output power however they are hard to find second hand for some unknown reason.. So at this stage, after 2hours of intensive research I am getting less certain of what would be the best option, so I could certainly use some advice...

Here is a petrol pump that seems good but then again I probably need a float/trigger for it.. and also looks a bit too good to be true

http://www.ebay.com.au/itm/1-5-WATE...524404?pt=AU_Pumps&hash=item461164b934&_uhb=1

Any help welcome!!

 

[Oldhydroman]

The Davey pump looks like a good enough choice to me. So what if the guy was reading the datasheet out to you - would you prefer him to have memorised it, or made up the numbers?

A petrol pump is going to be a bit of a pain to start and stop automatically (you will need a float switch and an electric start on the engine and batteries and battery chargers etc. and this is going to push the price up loads). If you don't have it automatically starting then someone has to be there all the time to deal with it otherwise the sump will overflow. Oh yes, and someone has to keep on buying petrol for it. I think an electric pump would be much more convenient.

Just remember to have a decent size overflow on the top floor - otherwise the drums will overflow if the toilets aren't being flushed often enough. You might also want to fit a non-return valve to the pump outlet so that your 20 metre long vertical feed pipe doesn't empty back through the pump every time the pump stops.

Check on the volume available in your sump and compare this with the flow rate at 20 metre head. You need enough differential between the "switch-the-pump-on" height and the "switch-the-pump-off" height to prevent the pump from running for very short periods - I would aim for a minimum run time of 1 minute.

 

[vonz33]

The Davey pump is $550 I forgot to mention that sorry... So it is not an option.

But you are right, an electrical pump would be the go as we can use the extra circuit that is fo use of the property manager, that's his gig to pay for water evacuation after all.

Now my next question is: Is this pump

http://www.ebay.com.au/itm/NEW-KULL...=AU_Pool_Spa_Beach&hash=item4ac6a8441d&_uhb=1

going to do the job as well as the Davey's? It is rated at 1500W, that means 1.2HP... the Davey is 800W only and is apparently good enough. It is a multi stage though but the Kuller one is double the power. Thing is, is that if you read the datasheet it states 10.5m Max Height (thats a bit vague to me).

So is the power rating directly related to the weight of water it can propel? You would think so but the Davey one says max total head 26m for 0.8Kw and the Kuller says Max head 10.5m max height and offers 1.5Kw so how does that work??

 

[LittleInch]

Are you for real?

Read the spec. Your ebay unit is doing 360l/min compared to your other unit of 80.

By the way 1hp is approx 760w.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[vonz33]

Hello LittleInch

How am I supposed to know that flow speed is related to the amount of water the pump can push up? If you know this figure from your previous education it's certainly a blessing, because personally I do not know that

Are you saying that the Kuller will do the job in my situation? It says max hear 10.5m...

Thanks

 

[Artisi]

Pump the water out into the street and save yourself and everyone else all the drama of sorting out airy-fairy pump applications considering you only $200 to spend.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[Oldhydroman]

Decades ago I worked on a project which entailed close liaison with a well renowned firm of consulting civil engineers. One of the consultants sort of took me under his wing and gave me an excellent piece of advice: Any fool can build a bridge which stays up, but it takes an expert to build a bridge which only just stays up.

So. here's the position as I see it. You've been tasked with solving a particular problem - part of which is that the budget is just $200. It's no use redefining the constraints to fit in with the existing solutions, i.e., my solution requires $600 so the budget has to be increased. If a solution requires $600 then it doesn't solve the whole problem and isn't a solution. Hundreds of the contributors on this forum could come up with a $600 system, but you're asking for someone to give you a steer to a solution that will cost just $200.

If an engineer has to cost his time at $200 an hour then spending a couple of hours to save $400 dollars isn't viable - this might explain the lack of responses. I presume the time you spend sorting it out isn't costed against your $200 budget so you can spend a few hours sourcing the parts you need from: pond equipment suppliers, domestic pump suppliers, horticultural equipment suppliers etc.

So here's your steer: a submersible pump is more expensive than an equivalently rated surface mounted pump. Look for a small, single phase, general purpose, multistage centrifugal pump. You should be able to get a 0.33 kW, 35 metre head (max) unit for about $130 dollars. Then you need a small float switch which is man enough to be able to handle the current needed for your pump. You can get such a device for about $40. Then you need a foot valve on the free end of your suction hose ($20) and, finally, some suction hose and hose clips ($10). You might have to search around a bit for a mains lead, plug and connection box (but you've already found the vertical hose and drums so I presume you have the facility to "acquire" stuff as necessary).

Hope it all goes well for you.

 

[NegativeZero]

http://legacy.shurflo.com/pages/home.html

small pumps with a lot power.

 

[vonz33]

Thanks Oldhydroman for your outstanding contribution to my thread.

As you guessed, I have some facility to "aquire" stuff as there is a lot of it around. So between the tip shop and whatever fittings and valves etc etc that is already available in this magnificent industrial heritage building where I just moved in is more than enough for all the bits and pieces topics. All I need is to find the pump that will deliver, and for a few years down the track, this is why I am taking the time to research and document myself and as well I like to know what I'm doing instead of taking the advice of the first salesman for granted.

Now, question related to power rating: Is the power rating of an electrical pump directly related tho the max head?

 

[Artisi]

Power is related to flow and head.
QxHxSG / 102xeff% in metric terms

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[vonz33]

And as well if you can show me a model of this ideal 330w pump that works up to 35 meters that would be even more outstanding!

 

[Artisi]

How about installation and commissioning?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[vonz33]

I finally scrapped a float switch from a dead pump on the site and found a 600w transfer pump on special for $79 at the hardware store. The label is stating 35m head. Hopefully that will work out.

Not too impressed about the efficiency though... but will see how much it will take on the bill, hopefully not too much. I'm guessing that the more the power, the quicker the draw so the shorter the use.

Thanks for your help.

 

[Oldhydroman]

Sorry, I was away for the weekend and didn't pick up on your request for details of the pump I suggested - anyway, you seem to have found a suitable candidate.

With a centrifugal pump you will have maximum flow rate at minimum head (outlet pressure) and zero flow rate at maximum head (the point at which the flow becomes zero is defining the maximum head). You need to pump up 20 metres so if you choose a pump with a maximum head of just 20 meters you won't actually get any flow into your drums. For this reason I suggested a pump with something like a 35 metre maximum head. You will only be half way along the "pump curve" at 20 metres head and so you will still get a reasonable flow.

Do check that the float switch is man enough to switch the motor current - remember that there may be be a current surge when the motor starts (the magnitude of the surge depends on the exact type of motor). If you are in any doubt then use the float switch to turn on a relay (energise the coil) and let the relay contacts turn on the motor.

You need to be super careful with your insulation and ingress protection if you are reconnecting an old float switch. If you have any concerns about inadvertently giving someone an electric shock then use a very low voltage for the switching circuit (say 12 V DC) and use a relay with a 12 V coil to switch the mains voltage to the motor. Even then do make sure that you are using a suitable residual current circuit breaker to turn the whole thing off in the event of any leakage of electrical current.

Also check carefully that your newly acquired float switch has the right operating function. You need a float switch for emptying a vessel: this will turn the pump on when the fluid level rises and stop the pump when the fluid level is low. Conversely, a float switch for filling a vessel will turn the pump on when the level is low and stop the pump when the level is high. Some float switches have change-over contacts so you can choose the sense you want by just using the wires that apply to that particular duty. Make sure the unused wires are properly terminated, segregated and isolated. If your float switch does have the wrong sense then you can overcome this by using a relay with normally closed contacts - when the switch contacts close this will energise the relay coil: the opening relay contacts will then stop the pump.

Don't forget the overflow facility otherwise the pump will overfill your drums if there is a greater supply from the sump than usage in the latrines. Your overflow has to be able to cope with the maximum flow from your pump. Your overflow line might have to be bigger than your delivery line.

Don't forget the foot valve at the free end of the suction pipe. Without this the delivery pipe will empty back through the pump every time it stops. If your sump is small and your delivery pipe is big then you could get a ridiculous situation occurring where the pump stops and then the flow back from the delivery pipe raises the level in the sump enough to restart the pump... you can see where this is going can't you!

It may be that your foot valve isn't perfect (especially if it's one you found or made from spare parts) or some debris might get under the sealing surfaces and allow the delivery pipe to slowly empty anyway. You might want to ensure your suction pipe has a small upward loop in it to prevent the pump from emptying completely otherwise you will have to keep re-priming it.

Finally, your suction hose to the pump has to be a type that has some helical or rigid reinforcement to cope with the slight vacuum that will be in that part of the circuit. Use a clear hose if you can because then you can see what is happening. Some rubber hydraulic hoses, for example, can de-laminate inside; they can look fine from the outside but have actually collapsed internally because of the greater outside pressure.

And finally finally, do send us a photograph of the completed installation - some of us that now only drive a desk can get a little nostalgic for the days when we actually built something from odds and ends and it worked just great.

DOL

 

[vonz33]

Thanks so much for all this... I sure should send you a box of chocolates at some point if it all works out!!

Will keep your paragraphs handy and refer to it at every step of the operation, I like your idea of relay, it's a very good one.

I performed continuity test on the float switch and seems to operate the way I need. It is rated for a 550w system so I have a chance.

Will update this post with photos and comments during evolution process and finalised job, I owe you this as at least as a bare minimum

Thanks again sir.

 

[vonz33]

Here we go. $79 dollars later. (Well... I spent 200 in the plumbing part)

The system is running. I will add another 2 drums at the top in order to achieve more capacity. A few fiddle here and there but at least we have a flushing toilet, that was the main problem. It is now fixed. The house plumbing network may now start.

https://plus.google.com/u/0/photos/...5954910247245722578&oid=115722038923057297195

This set of pictures is dedicated to Old Hydroman that helped on the theory part and dedicated also to those who would not believe it was possible with a small budget <$200.

Enjoy.