Bore hole pump experts can help?

[bankruatsteve]

So, I have a bore hole about 30m deep (I think) and we have the kind of pump that pumps water down and then sucks it back up for delivery. (that's my interpretation)

Well, now the pump doesn't run (I'm going to check the capacitor, etc. for electric but it's not easy for me to do - under the short roof - so will have to get somebody else to help for that.

Anyway... my question is: should I need to replace the pump, would I want to change to a submersible type or stick with the same (2-pipe) option?

Any knowledgeable or experienced replies welcome.

Thks, Steve.

[IMHO]

There are a number of pro's in favour of a submersible pump:

* Significantly lower power usage per litre of water flow. A good 350W submersible can easily outflow a 1500w above ground pump.

* Capable of much higher head heights vs the suction+head height of above ground.

* Silent vs not silent

* Cheaper

* Does not need protection from the elements

Cons:

* Most do not have any inbuilt pressure switch - you'll need to add one in yourself (or manually switch it on/off)

* If the pull rope/cable breaks, you're never getting it back out of the hole

* Tedious installation process

* if your bore's mesh filter breaks (letting dirt/sand in) you have a real task on your hands..

* Requires the best grade (13.5) PVC and glue - but you should be using that anyway

Edited September 15, 2013 by IMHO

[bankruatsteve]

For what it's worth... I got a guy to pull out the pump and I tested the capacitor (which discharges OK) so I'm guessing something in the motor has fried. This pump has been working OK for 3-4 years and was told it's a much cheaper option than a submersible. I don't see any brand identification on it so who knows where they come from.

[Crossy]

That looks very like a LuckyPro jet pump, HomePro have them.

How did you test your capacitor? To be honest the odds are on it being duff easiest test is replacement, does the pump buzz when powered but not turning?

If you pull the pump housing can you turn the impeller?

[IMHO]

For what it's worth... I got a guy to pull out the pump and I tested the capacitor (which discharges OK) so I'm guessing something in the motor has fried. This pump has been working OK for 3-4 years and was told it's a much cheaper option than a submersible. I don't see any brand identification on it so who knows where they come from.

Try a different shop - submersibles are normally cheaper because they need a much smaller motor to achieve the same/better result.

[Naam]

For what it's worth... I got a guy to pull out the pump and I tested the capacitor (which discharges OK) so I'm guessing something in the motor has fried. This pump has been working OK for 3-4 years and was told it's a much cheaper option than a submersible. I don't see any brand identification on it so who knows where they come from.

Try a different shop - submersibles are normally cheaper because they need a much smaller motor to achieve the same/better result.

au contraire! a submersible of same capacity is more expensive than a jet pump.

[bankruatsteve]

Boy do I feel stupid.

But first... I've always "tested" a capacitor by connecting to the ohmmeter (to trickle it) and then seeing if there is DC voltage drop: just proves it's alive vs. dead.

And, yes the impeller was nice and free.

Took it into a shop and he plugged it in - works! <deleted> So, I get back and plug it in, not work. This is on a switched outlet that I had already "tested" with a light bulb. So, I took out the outlet and it was full of jing-joke eggs and other crap. Tested the voltage and the top switch (which we have the pressure pump plugged in) was good. The bottom switch was only giving 50-60v and then went completed dead after I tried to "fix" it. So, I fixed it again with a big hammer and installed a conventional outlet. Now, I need to get the little guy back to re-install the pump. All that for a crap switched outlet. T&J brand btw. I've had issues with that brand before so never again for me.

[Crossy]

Boy do I feel stupid.

Nah, not stupid, and you won't make that mistake again.

We have issues with those microscopic ants getting in light switches and the pump pressure switch. Once a few have been crushed between the contacts dismantling and a thorough clean is required.

[bankruatsteve]

What I feel stupid about is that I ASSUMED it was an electrical problem with the pump. Several times in the past, turning it on had the same result: no buzz, click, no nothing. So, I got the wifey to whack it with a rubber hammer and voila, it would start right up. In retrospect, we don't use it that much so maybe just flicking the switch a few times would have had the same affect. (?) Eventually, the crap that got inside the switch must have insulated something from working.

[Crossy]

Ah yes, assume can make an ass out of u and me.

Been there, bought the (several) t-shirts

[IMHO]

For what it's worth... I got a guy to pull out the pump and I tested the capacitor (which discharges OK) so I'm guessing something in the motor has fried. This pump has been working OK for 3-4 years and was told it's a much cheaper option than a submersible. I don't see any brand identification on it so who knows where they come from.

Try a different shop - submersibles are normally cheaper because they need a much smaller motor to achieve the same/better result.

au contraire! a submersible of same capacity is more expensive than a jet pump.

if you're talking Watts, yes, if you're talking head-height or flow rate, shop around

[bankruatsteve]

Just to finish this one off... I decided to take out the roof over the pump and re-install myself (the roof thing was kind of ugly anyway ). So, everything copacetic again. I still think a submersible pump would be a better solution, but with my (I guess it's called?) jet pump working again - I will stay with that. It's not very efficient and have to cut the output flow to low else it just gurgles and does nothing. So, it's not the best but it's working so there you go. There I go.

[crazykopite]

Submersible any day just for the pressure alone !!!!!! if you can afford to do it go for it !!!!

[peter267]

You have a 'jet pump' with two pipe that join to a venturi device near bottom of the hole, not the most efficent but no working parts to speak of in the hole. Easy to have a pressure switch and bottle so pump switches on and off on demand.

Submersible pump can be installed on PE polythene pipe (PN10 grade - thats 10Bar pressure rating) and to depth you setting you can use a nylon safety rope but actually pull the pump up/down on the PE pipe for service etc. Its important to put the pump below water level!! but not so low its near the borehole screen - and that maybe difficult unless you know where, what depth, the driller put the screen - filter. Or if in rock maybe driller did not use plastic casing & screen? It could also be installed on the blue uPVC - glue fittings - maybe 32mm again PN10 - If you have to ever remove it can be removed in one snaking section if you have help to prevent to sharp a bend - or just cut and glue in new connectors. Good to fit a gate valve to choke back the flow if water runs dirty - well is being overpumed

Of course its Thailand and you have many choices of pump cheap Chinese to Danish Grundfos. Its important to get the correct voltage to pump motor - if borehole distant from your supply beware of volt drop in cable that too light for the power.

Jet pumps despite being inefficent make good sustainable household supply pump. Surely you can get a shop to check old pump out and maybe repair it? Check motor brushes maybe? Pumps start and stop a lot and this wears motors and brushes.

[Cuban]

When dealing with the "ant likes electrics" problem - I have used either a bug spray or ant-poison-powder when reassembling light switches and in the last instance a DVD player where ants had built up and fried around the contacts of the on/off switch.

I had read about this before but was surprised when I countered by first fried ants in this way.

Now a short spray on all new electrics seems to be the best preventative measure.

Allow the moisture to dry before sealing up any assembly where there might be a spark obviously so just a dry residue remains.

[AussieRob]

Jet pumps are used for a reason , normally down bores that are a very poor supply , or are in sandy ground .

To use a submersible in either situation is not an option .

[Artisi]

Sandy ground?? first-up a properly installed well shouldn't pass any sand after initially being developed and secondly, any sand in a jet pump is just as detrimental as in a down-the-hole bore pump. Sand is sand and abrasive to pumps especially in high velocity areas such as a "jet-pump" venturi which will suffer considerable erosion.

Edited September 30, 2013 by Artisi

[stevehaigh]

i just bought a jet pump from homepro. can't remember the brand, i think its japanese

anyhow its 1HP and i think it should work fine in my well (11m deep)

but after a day of f'in with it, i'm all out of ideas.

i put the plastic venturi thing in the end valve thing in the hole in the big pipe. i connected my 1" and 1 1/4" pipes to the pump. i bought a decent quality 1" none return valve for the inlet end because the plastic one that came with it leaked.

i primed it and checked the water level was stable for 5 mins, so no leaks in the pipes or the none return valve.

so i plug it in and it spits out a bit of water, presumably the stuff that was primed into the pump body. then nothing, just sits there gurgling.

does anyone have any idea what i could have dome wrong?

thx

[Crossy]

Assuming everything is hooked up right (non-return valve the right way round?), not really much to go wrong.

When you prime it you should ensure the 'up' pipe in the well is full (disconnect it at the coupling and fill with the hose), any air in there will cause the pump to lose prime and sit there gurgling.

Note that jet pumps are inherently self-priming, once the housing is full of water they will re-prime automatically, but it can take a long time to get the initial charge in, filling the inlet pipe should shorten the process.

Maybe you just didn't wait long enough, go and make a cuppa whilst it gurgles

EDIT and leave the pump outlet disconnected from the house piping until it primes up, easier exit for any trapped air

[Canada]

Sandy ground?? first-up a properly installed well shouldn't pass any sand after initially being developed and secondly, any sand in a jet pump is just as detrimental as in a down-the-hole bore pump. Sand is sand and abrasive to pumps especially in high velocity areas such as a "jet-pump" venturi which will suffer considerable erosion.

"properly installed well"

Thailand

[Canada]

Info. One year old prices

A 4" - 1 1/2 hp Mitsubishi submersible (2" out) will run you about 18,000 baht.

A 4" - 2 hp Mitsubishi submersible (2" out, 200 litres/min) will run you about 24,000 baht.

A 3 " - 1 hp Chinese submersible (1" out, 40 litres/min) will run you about 4500 baht.

Frankiln pumps will price in the same range as the Mitsubishi's - give or take a bit.

I don't know about jet pumps, but by the looks of the pic my guess is that price wise, it would compare to the Chinese 3" submersible....maybe a little more, but not much. Not sure of it's capacity but probably in the same range as well. (40 l/min)

Edited March 25, 2014 by Canada

[Canada]

On the topic of pumps and stuff.

I've been running several kilometers of irrigation drip tape off of several different pumps, with some success. I want to expand my system(s) and pump out of a pond with a higher pressure pump. We are just getting electricity at this particular piece of property and in enquiring about pumps, motors and stuff at the local store, they figure that I'd need a 10 hp electric to run the pump that I want. They have both and I've bought a lot of gear off of them already, so I do trust them....to some extent. I trust that they won't knowingly steer me wrong or rip me off.

Can anyone tell me how much it'd cost me to run a 10 hp electric motor for 12 hours under load? Or could someone outline the equations to help me figure this out on my own?

Right now I am paying about 250-300 per day in diesel fuel (per machine) to run 10 hp Kubotas, and I'm running 3 machines, but only two systems. I think I can pump the same amount of drip line with one pressure pump as I do with 2 centrifugal pumps on the top of wells.

I'm going to test my theory first by running the large pump, on a large system off of a Kubota, but I wonder if 10 hp electric would be more efficient. I'm not that bright about these things.

Naam??

Crosby??

Edited March 25, 2014 by Canada

[Artisi]

Assume you are talking about a 10hp 3 phase motor.

For pumps of this size you need to be a bit selective in what you choose. You should establish what flow needed and then calculate the pressure required to give this flow. From here you can select a pump that will give you the best efficiency, with a motor also selected to run efficiency. Just using a 10hp pump is pretty dodgy in terms of value for your money. Power is not cheap and an incorrectly sized pump / motor can burn-up a lot of money which would have been better spent on a correctly sized pump of good quality. 1st rule of pumping - don't purchase your pump based solely on lowest cost.

You also need to carefully size all your pipework, pipes of too small a diameter burn up lots of power ( this = money) - head loss thru pipes changes with diameter to the 5th power, to give you a rough and ready example -- based on steel pipe (no PVC friction charts to hand at the moment)

10GPM thru 1/2" pipe equals 97ft head loss for every 100ft run of lineline

10GPM thru 1" pipe equals approx. 7ft head loss for every 100ft run of pipeline.

Think the above re pipe diameter is pretty self explanatory.

Give us more info - so we have some facts and figures.

[Canada]

Ok, I'll try.

Running 100 -300 meters of 2" plc. Then, off of that, I'll run about 10 kms of 5/8" drip line. The 2" pipe varies depending on which system I am sending water to. We'll run about 8 of these systems that will operate independently of each other but all connected to the same pump system.Each system for 2 days on a continuous cycle. The entire field will get water every eight days.

I'm not sure what pressure we are running at. We're not that advanced yet that we put a gauge on the systems What we do is open the appropriate number of valves for the supply that we are getting. When the system is pressurised and the drips are dripping well, that's how big our system is that day. So far what we are getting is about 3-5 kms of drip line off of one pump depending on how far we are having to pump the water to the system and which pump we are using.

We are using a few different configurations of pumps. A 2 hp submersible, a 3" surface pump on a well, a 2" surface pump on a well, and one or the other surface pumps pumping out of a pond (best scenario). The submersible works well too if we are not sending the water too far or uphill.

The pump that I am looking at is not that expensive. It's the most expensive that they have of this type. I'm not a fan of buying cheap and then re-buying later. It is not designed to pump out of a well. It will pump out of a pond. They say it will pump up to 1 bar for 1 km at 2" dia. They recommend a kubota but say that a 10 hp mitsubishi will work well as well. They call the pump a "pump reng dan" in Thai. It means pressure pump.

Any of this helpful?

[Canada]

Last note. I need to get 10 kms of drip line to run off of one pump for this to be worth doing. I suppose a handy tidbit of missing info is what pressure the drip line is supposed to be operated at. That is something that I don't know. Not yet. Global is a half day trip. My answer is there. I think.

[Artisi]

Ok, Thanks for the info - unfortunately all too general and not enough specific data to make any meaningful comment. Saying that, I guess a lot of drip irrigation systems just evolve without any real hydraulic input. However, it can be calculated and fairly accurately given good data and thought in how the system is laid-out.

Data needed is a dimensioned lay-out of the system.

Pipe lines sizes also shown on the system lay-out

Number of drippers on each leg or run of drip line

any change in elevation from water supply to the highest point in your system

From this we stand a chance of calculating the total flow rate and the pressure needed to drive the system at the flow required -- this of course will dictate the pump / motor needed to meet your requirements.

This is not my field of pumping expertise so that information / resources available is unknown, but I assume there must be a lot on info and even sizing info available from the internet. Worth a check

Edited March 26, 2014 by Artisi

[Artisi]

Canada

Quick Google check came up with the following, looks good and should go a long way to help you, at least in getting your thoughts together.

http://irrigation.wsu.edu/Content/Fact-Sheets/Sprinkler-and-Drip-Equipment.pdf

System layout is still important but this article doesn't address this subject.- I can possibly help you if required.

[Canada]

Canada

Quick Google check came up with the following, looks good and should go a long way to help you, at least in getting your thoughts together.

http://irrigation.wsu.edu/Content/Fact-Sheets/Sprinkler-and-Drip-Equipment.pdf

System layout is still important but this article doesn't address this subject.- I can possibly help you if required.

Ok. Thank you. Just a quick skim is making me sweat. I'll read it a little slower and see what sinks in to the old wood block.

Really, I have most of the system built already and there are many variables in finishing it to the size that I want. Some of these variables are within my control. That means that I can customise the system somewhat to fine tune it.

I am really more interested in the electric consumption of a 10 hp motor run at 50 % load capacity. Probably I should just google THAT and start there.

Thanks

[Pacificperson]

If you are not using a lot of lift in the well, your two inch pipe will be the limiting factor in the system. There is only so much water that you can move through it. I would guess that anything over 2-3 hp will just be wasting energy and money. If you want a bigger pump for more flow, then you are going to have to use a larger pipe.

Take a look at this chart: http://flexpvc.com/WaterFlowBasedOnPipeSize.shtml anything much over 125 gpm is going to cost more energy than you want to pay for.

Edited March 26, 2014 by Pacificperson

[Pacificperson]

A second thought is that you need to think about flow and not about pressure. How much water do these driplines put out per minute? What is their rating in gpm or lpm per 100 meters? Are you using emitters? If so what are they rated and what is your spacing? 10 Km of 1 gph emitters at .5 meters needs 333 gpm, and I don't care how big your pump is, a 2 inch line is not going to move this much water. Remember, what you want to do is to minimize the baht per cubic meter of water delivered to your crops over the 3-10 year lifespan of your system. From the limited information you have given, I would say spend on pipes and not on pumps.