Aspiration Condition for a Water Pump

Hi Gabriel

You are coupled to (being supplied from) a water reticulation system that is clearly under designed and the situation may even deteriorate in the future when more users are connected or the demand increases.

The best solution would be for the authorities to improve the system.

You could also increase your storage capacity – a 2 cubic meter tank will be equivalent to 60m³ per month.

Is it possible to supply some detail regarding the reticulation system?

Is the heights given above the mains pipeline?

You would like to install the pump 3m above the water level in your part of the branch pipe.

Gabriel --

You need pump for domestic water wells commonly known in the USA a "jet well pump" or "jet pump" Either is a good search string but the phrase "jet pump" also refers to the type of pump used to propel some boats and most personal watercraft or "jet skis".

What I'm talking about here is a small centrifugal pump for water wells that has a suction chamber to retain water within the casing and a check valve below the inlet water level in the suction pipe (sometimes called a "foot valve" or preferably a special "eductor" or "ejector" that acts as an aspirator as you call it using a flow of high pressure water from the main pump above to "lift" the water in the suction. The eductor lifts the water into the centrifugal stage of the pump which then pumps it up to the elevated tank or to the higher pressure of a closed water tank.

This type of well pump system is used by the millions in the USA for shallow domestic water wells in rural areas away from municipal water systems. A typical pump and eductor (jet) package without the piping and controls typically sells in the range or US$300-$500 and can be found from a variety of online sources as well as larger hardware stores in rural areas of the USA and Canada.

A diaphragm pump will work but will be much more expensive and may not last as long as a specially designed well pump of the" jet pump" type.

Search term "jet pump" will get you at least some hits on sources of this type of hardware and descriptions of how it works.

Here are some useful links I got from a Google search:

http://www.animatedsoftware.com/pumpglos/jet_pump.htm

http://www.popularmechanics.com/home_journal/how_your_house_works/1275136.html?page=3

http://www.nationalpumpcompany.com/Documents/OIM/Betta%20Flo%20IOM%20Jet%20Pump.pdf

http://www.inspect-ny.com/water/JetPumps1Line.htm

http://www.watertanks.com/images/pdf/watertankscom-goulds-boosterpumps.pdf

http://www.keidel.com/mech/wellpumps.htm#shallow

Ed Weldon

Gabriel,

This is a common problem in Mexico (or any Latin American country). The thing is, your water holding tank is more than likely on your roof to gravity feed your house and also to warm the water through out the day. Hence the locals usually rather shower mid day...

More and more with places here people are adding a holding tank at street level that maintains a constant supply on demand via lift pump to the tank above

OR

Simply install the tank bellow with a pressure set (small pump with a pressure tank equipped with a bladder)

Theres no better investment of a couple hundred dollars to have a good shower at the end of the day, not to mention your toilet tank being ready to flush when you need it most

If you need detailed info I can get it, but check your local places first, I'm sure someone there has done this.

.....

I will give you a "good answer" for that....

Wangito.

Sounds to me that you are trying to suck the water up - at sea level and normal atm. pressure you can only suck up to +/- 30 ft with an efficient pump. (This is a vacuum leg!)

Better to fill a tank at ground level and then pump it up to the header tank height becomes less important.

If I understood you well, you have an elevated water tank to which water will not arrive due to low line pressure.

If this is the case, just install an in-line pump that will have enough head to reach the tank. If there is always water at the pump intake, it makes no difference which type you use. If you need to lift the water to the in-line pump, make sure suction is no more than 6-7m for proper work.If it is,you need to use Jet pump as one poster already recommended. If there's a chance that the intake may be dry, you will need a primer system, If I were you, I would throw away the reservoir tank and replace it with pneumatic tank. this way you will have water and as much pressure as you want. Of course, you will still need the in-line pump.

Wangito.

Hi to all people, thanks a lot for your response: I have many problems with my water installation, due to my house is from 1^st floor to 3^rd floor, that is I am not the owner of the floor at street level and, say, I have some "communications problems" with the lady that owns the street level. There is also a bad design from the very beginning of the building, but while I argue with the constructor I need to settle my problem.

So, I can't access to piping to put a check valve below water level and in this conditions, I suppose that a "jet well pump" as Ed Weldon advise, is not possible. Of course a tank a street level would be the correct solution (Tim advise), but no possible, at least now.

For the above reasons I thought in a "diaphragm pump", because I thought that will aspirate directly from the street line. The suction needed will be not more than 5 or 6 meters.

Thanks again.

Gabriel,

At this point only you can make the decision on the BEST route to follow in getting this problem solved. As you know best what equipment is readily available in your area.

Ive lived in many different places in South Mexico and I can tell you this. Water availability and pressure is the first thing I look into before moving into a new place.

Good luck in your quest for a long relaxing shower

hello from shankar, bangalore india

what you need is a pump to boost the pressure shortfall required to push water to your overhead tank level. a normal centrifugal pump driven by an electrical motor will do. you have to connect the water supply pipe to the suction side of the pump and the delivery pipe to the tank the pump need not be kept at any height, ground level will do. in many countries, it is illegal to connect a municipal supply line to pump directly. pls check. in such case, use a sump for collecting water for subsequent pumping.

without the rate of discharge details, it is not possible to suggest the motor hp and pump size. for most domestic purpose, 1 hp may be adequate and the pump could be single or two stage centrifugal with 1 to 1.5" suction/delivery size.

shankar

refurb_india@yahoo.com