I know pumps have a max height they can pump to called head. If you had a container of water and wanted to pump it higher would the pressurized things they use on wells give you a higher head?
I know pumps have a max height they can pump to called head. If you had a container of water and wanted to pump it higher would the pressurized things they use on wells give you a higher head?
I do know that a pump can only pull, at most from 32 feet below it. Something about gravity and the laws of physics. That's why some pumps have like a jet primer thing to pressurize the system first to negate the head pressure.
This is all very vague from engineering sophomore year. I may be VERY wrong. Lolz.
If no actual engineers step in and supply the answer, I'll contact one and see if I can get anything for you.
The trick is to put the pump at the bottom if you can. Pumps can push a nearly unlimited distance, but can only pull a much smaller distance. 32 feet is the ideal world max suck, real world is less.
wvumtnbkr said:I do know that a pump can only pull, at most from 32 feet below it. Something about gravity and the laws of physics. That's why some pumps have like a jet primer thing to pressurize the system first to negate the head pressure.
This is all very vague from engineering sophomore year. I may be VERY wrong. Lolz.
A suction pump can only pull 32ft (ish, based on atmospheric pressure, so above sea level can throw that off) of water.
A submerged pump has no such issues and is basically limited by how big of a pump it is.
To Stampie's original post, fairly sure danvan said all that needs to be said to answer it.
Head also has some inverse relationship to flow for a given pump.
Ie an example pump might flow a lot when lifting 1 foot, but only flow a little if the needed lift or "head" is 10 feet.
Stampie- I think you need more head. From your pimp. Er, pump. On your pump.
Just keep pumping. It goes on and on.
I tried to look it up but got confused trying to understand Pascal's Law. TIL there is pressure head (height of discharge above pump) and suction head (height of pump above water level).
I want to know why at the same height and diameter of the discharge hole and same length of the pipe, it doesn't matter if the pipe is 2" or 2' in regards to flow or pressure?
barefootcyborg5000 said:Not where I though we were going... And I don't know if that's hood or bad.
Same
In reply to VolvoHeretic :
Rain water collection system to provide water to an off grid house. I can think of alternatives like never let the rain water get to ground level but I also don't want a water tower.
In reply to Stampie :
I’ll let the professionals handle the wiseacre comments, LOL.
About pumps, is this a domestic water well pump? Is the pump down in the well pushing water up or above the well trying to pull water up? In reference to pumps there are several “head” readings (typically in feet of water); suction head, discharge head and total (combination of the previous two).
Deep well pumps often use several stages of impellers to raise the pressure high enough to overcome the static head of the well depth. Static head pressure in PSIG for water is the total depth of the well in feet multiplied by .43. For example, a 100 foot deep well would need a pump that is capable of more than 43 psig to lift water to the top of the well.
Shallow well pumps often use an internal “jet” (actually an eductor) that uses some of the discharge water to assist the suction lift when the pump is above the water source. We use this type of pump with a pressure switch and a Weltrol tank to pump lake water at our island house for example. The pump is about 10 feet above lake level, we have the pressure switch set to come on when the tank drops to 40 psi and shut off at 50 psi. With a 10 foot lift and at 50 psi in the tank the pump would be at roughly 126 total feet of head (50 psi divided by .43 feet per psi is 116 feet plus 10 feet on the suction side.)
A centrifugal pump will have a defined total head that depends on impeller selection and pump speed. Manufacturers typically publish performance curves for different motor speeds (1,750 or 3,600 RPM being two common ones) for different impeller designs and diameters.
As previously mentioned a “Weltrol” tank is used to provide a storage volume to maintain a more consistent supply pressure and to allow the pump to build pressure and cycle off, it’s possible to adjust the pump pressure switch to a degree within the limitations of the pump. Sorry for the long form answer, let me know if you have more specifics, happy to assist.
Edit: while I was typing my novel... looks like you’re trying to get water up two stories or so. Measure the actual height, that’s the minimum discharge head you need.
In reply to 11GTCS :
No well. Think 3000 gallon tank that collects rain water from the roof run off.
In reply to Stampie :
Ok, what’s the total height from where the tank is to the upper most water tap?12 volt or 120 volt? What kind of flow are you looking for? Supply pressure? I should be able to find something and can post a link.
In reply to 11GTCS :
120 and possible 240. Normal household pressure so say 40psi min. Don't have anything built yet but I'd guess take off from top of tank to max height at 10 ft min 20 ft max.
In reply to Stampie :
Pretty sure a standard shallow well pump set up with an expansion tank is what you’re looking for. Standby, I’ll see if I can find something to link.
Here's a hammer store unit that includes the pump, switch and expansion tank. These are all 40-50 psi pumps and in the range of 10 GPM flow and suitable for weekend / cabin type use. I'd put this in a covered enclosure near your tank.
Similar one on the 'zon: https://www.amazon.com/Stainless-Shallow-Pressure-Control-Switch/dp/B01N4SH3G6
Wally world: https://www.walmart.com/ip/1-2-HP-Cast-Iron-nbsp-Shallow-Well-nbsp-Jet-Pump-with-24l-Tank-System/525611475
If you need a pump for a primary residence / higher flow rates and more continuous use you'll need to consider a set up with a larger pump piped to a larger storage tank. As an example, this is the Goulds pump we have at the lake house and includes a pressure switch: https://www.waterpumpsdirect.com/Goulds-J7S-Water-Pump/p96954.html?gclid=CjwKCAiAk--dBhABEiwAchIwkWgvajEwQI9hd7sssiE3ZQ1bfUEtyDxp8ggeuRC7lXb8qebyiUIKXhoC5mIQAvD_Bw
You'd need to add a separate pressure tank with that pump, this is similar to what we have: https://www.plumbingsupplynow.com/wx-202-well-x-trol-well-tank-20-gal-wx-202?gclid=CjwKCAiAk--dBhABEiwAchIwkRQI9pPMu8m-cd2TqPkcKajE6tnzKKzaRGdQTysvmvUSzf-B2V2bSRoCMkIQAvD_BwE
The 3/4 HP Goulds pump with (I think) a 20 gallon tank will keep up with a 1 1/2 bath house plus kitchen and washing machine. This set up is significantly more expensive than the first links but is meant for more constant use. Hope this helps.
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