Boreholes

[Gary A]

Years ago I lived in a village near Bangkok. The electricity went of on a regular basis for some reason. The water pressure was also so low that a pump was a necessity. During my morning shower before going to work, the power would sometimes go off and I couldn't even get the soap rinsed off me. Water eventually soaks up the air in the small pump tank and thats when you get what is called telegraphing. The pump cycles on and off causing a water pulse. The solution was buying an approximately 30 gallon stainless steel tank with a clear tube showing the water level. If the power went off I still had enough water to finish my shower and then some. It was easy to look at the sight glass once in a while and if the water level was too high a bicycle tire pump easily put more air into the tank. The stainless steel tank will last through several water pumps.

[salkhi]

greetings,

just a random one to see if anyone knows anything about

the ground conditions for a bore hole (for agricultural use) in Taptaan area, Uthai Thani...

Am drawing plans for an eco farm from uk at the moment, so am doing alot of guesswork,

thanks alot

[RamdomChances]

Sakhi you'd need to talk to the locals as the conditions vary so much

[sinom]

Chaps et al

very interesting thread.

I have recently installed a 45 m well at my house in Banglamung to service house and swimming pool and garden. My city water bill normally runs to about 2500 THB per month so the economics of installing a borehole system for 80,000 THB are fairly self evident.

The company I used performed a fairly professional job (for Thailand), installed a 6" jacket, with a 2" pipe insert with the pump attached. I can't remember the spec for the pump and it is now sunk down 45m. !! The pump was supplied with a box of tricks which includes a thermal overload circuit.

The water I get was tested and found to contain an excessive amount of particulates and slightly acidic.

So I've installed an active carbon filter system with particulate removal added. Tested the system and it's great ! I get perfectly clean water that's good for everything I need.

But........ here comes the problem ........... The pump runs inititially for about 5 minutes and then trips repeatedly on what I think is thermal overload.

If I leave it for a few minutes, perform a reset to the relay I can restart and get another 5 minutes. This is very frustrating.

The water coming of is fairly brown in colour and creates a small amount of mud sediment in my upstream screen filter. I was concerned that during construction some dirt may have gone back down the outer jacket and be fouling the pump. I can't fully remove the pump to inspect it without cutting up the 2" inner pipe on removal. So I removed it about two meters up and down to see what would happen. The result was that the pump ran for what seemed to be a little longer then tripped out again.

Does the collective experience on this thread have any advice on this?. My concern now is that the pump is under powered and stuggling to pump against a 45m head of water containing a degree of sludge and I will have to pull the whole thing out to inspect it, cutting up the pipe as I go, then possibly replace the pump, but not know if this is correct until the whole thing is back in place and I try again.

Thanks in advance

[Gary A]

Chaps et al

very interesting thread.

I have recently installed a 45 m well at my house in Banglamung to service house and swimming pool and garden. My city water bill normally runs to about 2500 THB per month so the economics of installing a borehole system for 80,000 THB are fairly self evident.

The company I used performed a fairly professional job (for Thailand), installed a 6" jacket, with a 2" pipe insert with the pump attached. I can't remember the spec for the pump and it is now sunk down 45m. !! The pump was supplied with a box of tricks which includes a thermal overload circuit.

The water I get was tested and found to contain an excessive amount of particulates and slightly acidic.

So I've installed an active carbon filter system with particulate removal added. Tested the system and it's great ! I get perfectly clean water that's good for everything I need.

But........ here comes the problem ........... The pump runs inititially for about 5 minutes and then trips repeatedly on what I think is thermal overload.

If I leave it for a few minutes, perform a reset to the relay I can restart and get another 5 minutes. This is very frustrating.

The water coming of is fairly brown in colour and creates a small amount of mud sediment in my upstream screen filter. I was concerned that during construction some dirt may have gone back down the outer jacket and be fouling the pump. I can't fully remove the pump to inspect it without cutting up the 2" inner pipe on removal. So I removed it about two meters up and down to see what would happen. The result was that the pump ran for what seemed to be a little longer then tripped out again.

Does the collective experience on this thread have any advice on this?. My concern now is that the pump is under powered and stuggling to pump against a 45m head of water containing a degree of sludge and I will have to pull the whole thing out to inspect it, cutting up the pipe as I go, then possibly replace the pump, but not know if this is correct until the whole thing is back in place and I try again.

Thanks in advance

You probably have a check valve (one way valve) installed just outside of the top of the casing. I would take the check valve out and allow the water in the pipe to backwash back down through the pump. Maybe even force more water down the pipe. That should clear any debris from the screen on the pump. To pull the pump a meter or so higher in the casing would also be a good idea. You should have some information regarding the pump capacity. Check to see if it is rated to push water the 45 meters. That is a deep well.

[Khonwan]

....., cutting up the pipe as I go, ....

I don't have a bore, but...it is my understanding that the inner pipe is threaded. Normal metal pipe is purchased in 6-metre lengths and are usually threaded. I suspect you have only pulled this pipe up a couple of meters and therefore have not seen the threads. Can anyone with a bore confirm this?

[sinom]

Chaps et al

very interesting thread.

I have recently installed a 45 m well at my house in Banglamung to service house and swimming pool and garden. My city water bill normally runs to about 2500 THB per month so the economics of installing a borehole system for 80,000 THB are fairly self evident.

The company I used performed a fairly professional job (for Thailand), installed a 6" jacket, with a 2" pipe insert with the pump attached. I can't remember the spec for the pump and it is now sunk down 45m. !! The pump was supplied with a box of tricks which includes a thermal overload circuit.

The water I get was tested and found to contain an excessive amount of particulates and slightly acidic.

So I've installed an active carbon filter system with particulate removal added. Tested the system and it's great ! I get perfectly clean water that's good for everything I need.

But........ here comes the problem ........... The pump runs inititially for about 5 minutes and then trips repeatedly on what I think is thermal overload.

If I leave it for a few minutes, perform a reset to the relay I can restart and get another 5 minutes. This is very frustrating.

The water coming of is fairly brown in colour and creates a small amount of mud sediment in my upstream screen filter. I was concerned that during construction some dirt may have gone back down the outer jacket and be fouling the pump. I can't fully remove the pump to inspect it without cutting up the 2" inner pipe on removal. So I removed it about two meters up and down to see what would happen. The result was that the pump ran for what seemed to be a little longer then tripped out again.

Does the collective experience on this thread have any advice on this?. My concern now is that the pump is under powered and stuggling to pump against a 45m head of water containing a degree of sludge and I will have to pull the whole thing out to inspect it, cutting up the pipe as I go, then possibly replace the pump, but not know if this is correct until the whole thing is back in place and I try again.

Thanks in advance

You probably have a check valve (one way valve) installed just outside of the top of the casing. I would take the check valve out and allow the water in the pipe to backwash back down through the pump. Maybe even force more water down the pipe. That should clear any debris from the screen on the pump. To pull the pump a meter or so higher in the casing would also be a good idea. You should have some information regarding the pump capacity. Check to see if it is rated to push water the 45 meters. That is a deep well.

The inner 2" pipe is PVC (please take note Khonwan, I think it's PVC all the way with PVC glued unions/connectors) joined by a threaded union to a metal flange plate which then has an elbow then another union onto my PVC pipe distribution system leading to the filters. Tonight I disconnected the top union, pulled the whole thing up about half a meter to acheive an easy resting place. I then angled a watering can over the discharge nozzle such that the water spout was pointing back down the 6" jacket.

I then ran the pump, to fill the can and then shoot the water back down the jacket. Same result - the protection circuit kept tripping about every 5 mins, but the water was relatively clear. I repeated this about 10 times to see if the pipe would show any signs of filling - it didn't. I also pulled the pump up and down a few times to see if I could "flush" the intake guard. - no real change.

There is no obvious sign of a check valve at the top end fittings on the pipe header.

The box of trickery is labelled as follows:

Sun motor submersible motorcontrol

Over current Protection

Pump = 1.0 hp

Any further clues / ideas

cheers

[chownah]

The good thing about PVC is that if you haul out the pipe and cut it then it is really easy to just glue straight connectors on where you cut it when you reinstall it...and the connectors and glue are really cheap so its a cheap and easy process to pull your pump and then replace it....all you need are straight connectors, glue, and a brush to apply the glue...and maybe a rag to wipe off excess glue if your a neat freak.

Just whatever you do don't drop the pipe and pump. When you reinstall the pump you might consider adding a tether so won't need to worry about dropping it next time....maybe you've got one already.

Chownah

Edited March 28, 2007 by chownah

[RamdomChances]

My inner pipe is threaded metal, think it just depends. If it's plastic and snaps your going to have probs getting the pump out unless you have a wire attatched as well.

[Lickey]

I recently had my borehole cleaned out to a greater depth, from about 15mtrs to 23mtrs, I wanted to buy a 2hp sub for this, but the man in the local shop advised me against it, saying a 1hp would be adequate for my needs, he also told me that a 2hp pump would need a 2in riser, {inner pipe} normal/std size for 1hp is 1.5in pipe, unless the drilling crew fitted an adapter because they had only 2 in blue?? please check pipe size again, if a 1hp pump is pushing water up a 2in pipe 45 mtrs and then some, thats quite a weight of water, perhaps this is why the overload keeps cutting in? is it the right control box for the pump?is it the one that came with the pump?also all modern subs have a one way valve in the top of the pump, so trying to backflush it wont help much, muddy looking water is normal on start-up, this is the water in the liner pipe, mine clears in 2 mins as soon as new water comes into pipe.

Being a realtive newcomer to boreholes ive talked and listened to local people and admired the helpful replies ive had on here from experinced members on this site, perhaps Chownah can help with the mathmatics of a 1hp 2in pipe, 45 mtrs ect, cheers,,

[chownah]

Thinking that a larger diametre pipe holds a greater weight of water so it is more difficult for a pump is, unforturately, incorrect. The things which create the work the pump must do is the PRESSURE AT THE PUMP DISCHARGE and the effort needed to get the water moving. The three things that will affect this are the depth of the water, the flow resistence (friction betweent the water and the pipe), and the velocity of the water (how fast it is flowing).

Depth: In any body of still water (important to remember we are talking about water that is not moving for this depth discussion), whether its a lake, a bathtub, a bore, or a pipe, the deeper you go the greater the pressure. It doesn't matter how wide the body of water is....it only depends on how deep you go in the water. This means that the diametre of the pipe does not matter when considering the pressure at your pump for still water (the pump is off).

Flow resistence: When water flows it "rubs" on the sides of the pipe and this creates friction....you can think of this as a force on the water that wants to keep it from moving...it is a force which acts counter to the flow and your pump has to work to overcome this force to keep the water moving......when you analyze the hydraulics you will see that this means that the pressure at the pump outlet is higher than for still water....this extra pressure gives the push that overcomes the resistence to flow. If you want to pump the same number of litres per minute through two pipes then the smaller the diametre of the pipe the greater the flow resistence assuming that the pipes are equally smooth on the inside surface. Also any bends will increase the flow resistence....I won't explain exactly why unless asked to do so as its probably just a distraction and not important why.

Velocity: To get anything moving that is standing still requires effort. The water in the bore hole is not moving and the pump makes it start moving up the pipe...this requires effort and the faster you want the water to move the more effort it will take. Think about throwing a ball...it takes effort...the faster you through the ball the more effort it takes.....water works the same way even though its a liquid. The faster the water goes in the pipe the more work the pump must do. If you have two pipes with water flowing in both at the same number of litres per minute then the pipe with the smaller diametre will have its water flowing faster (as measured in metres per second) than it will in the larger pipe. This means that it takes less effort for your pump to pump water in the larger pipe.

So..........using the smaller pipe will make your pump work harder because of flow resistence and higher velocity in the pipe.....and, while the larger pipe does indeed hold more water it actually decreases the work your pump must do.

Chownah

[sinom]

The good thing about PVC is that if you haul out the pipe and cut it then it is really easy to just glue straight connectors on where you cut it when you reinstall it...and the connectors and glue are really cheap so its a cheap and easy process to pull your pump and then replace it....all you need are straight connectors, glue, and a brush to apply the glue...and maybe a rag to wipe off excess glue if your a neat freak.

Just whatever you do don't drop the pipe and pump. When you reinstall the pump you might consider adding a tether so won't need to worry about dropping it next time....maybe you've got one already.

Chownah

Chownah - agree with the PVC bit not too difficult a job. The tether appears to be a green nylon rope that disappears down the jacket with the pump cable. It looks like I'm going to have to pull the whole thing up. !!

My inner pipe is threaded metal, think it just depends. If it's plastic and snaps your going to have probs getting the pump out unless you have a wire attatched as well.

RandomChances - I think I prefer the PVC pipe, with respect to possible rusting but do pay heed to the point of broken pipe !!

I recently had my borehole cleaned out to a greater depth, from about 15mtrs to 23mtrs, I wanted to buy a 2hp sub for this, but the man in the local shop advised me against it, saying a 1hp would be adequate for my needs, he also told me that a 2hp pump would need a 2in riser, {inner pipe} normal/std size for 1hp is 1.5in pipe, unless the drilling crew fitted an adapter because they had only 2 in blue?? please check pipe size again, if a 1hp pump is pushing water up a 2in pipe 45 mtrs and then some, thats quite a weight of water, perhaps this is why the overload keeps cutting in? is it the right control box for the pump?is it the one that came with the pump?also all modern subs have a one way valve in the top of the pump, so trying to backflush it wont help much, muddy looking water is normal on start-up, this is the water in the liner pipe, mine clears in 2 mins as soon as new water comes into pipe.

Being a realtive newcomer to boreholes ive talked and listened to local people and admired the helpful replies ive had on here from experinced members on this site, perhaps Chownah can help with the mathmatics of a 1hp 2in pipe, 45 mtrs ect, cheers,,

Lickey - good info. I should have paid more atention to detail when the put the pump in the ground!! It could well be a 1.5" pipe, I didn't actually read the writing on the pipe I just assumed it was 2". I will check further. The control box came with the pump and was fitted by the contractor - I assume it's the correct one. You are also correct in that the water clears pretty quicly when it starts to run. My contractor assured me the 1hp pump was amn enough for the job. As stated above I think my only remaining option is to pull the pump and have a look see.

It's so frustrating that I appear to have a good supply of water down there but can't get the stuff to the surface

thanks for the suggestions and advice so far

[RamdomChances]

RandomChances - I think I prefer the PVC pipe, with respect to possible rusting but do pay heed to the point of broken pipe !!

It is galvanized pipe. I don't think it really matters that much as long as you have some way to pull the pump up if needed.

[chownah]

If you should decide to go with galvanized pipe be aware that galvanized pipe is heavy and 45 metres of it will weigh alot...especially if you use 1.5 inch pipe!!!!!...or larger!!!!!.....so you will need to be sure that whatever holds the pipe up (quite often the liner) is adequate.....a pvc boreliner might not be strong enough...I don't know.

And by the way....I'm sort of surprised that a 1.5" pipe is used with a one horse power pump. All the one horse pumps I've seen have 1" outlets and are recommended for use with 1" pipe.....but then I have not seen all the pumps in the world either.

[Gary A]

Chaps et al

very interesting thread.

I have recently installed a 45 m well at my house in Banglamung to service house and swimming pool and garden. My city water bill normally runs to about 2500 THB per month so the economics of installing a borehole system for 80,000 THB are fairly self evident.

The company I used performed a fairly professional job (for Thailand), installed a 6" jacket, with a 2" pipe insert with the pump attached. I can't remember the spec for the pump and it is now sunk down 45m. !! The pump was supplied with a box of tricks which includes a thermal overload circuit.

The water I get was tested and found to contain an excessive amount of particulates and slightly acidic.

So I've installed an active carbon filter system with particulate removal added. Tested the system and it's great ! I get perfectly clean water that's good for everything I need.

But........ here comes the problem ........... The pump runs inititially for about 5 minutes and then trips repeatedly on what I think is thermal overload.

If I leave it for a few minutes, perform a reset to the relay I can restart and get another 5 minutes. This is very frustrating.

The water coming of is fairly brown in colour and creates a small amount of mud sediment in my upstream screen filter. I was concerned that during construction some dirt may have gone back down the outer jacket and be fouling the pump. I can't fully remove the pump to inspect it without cutting up the 2" inner pipe on removal. So I removed it about two meters up and down to see what would happen. The result was that the pump ran for what seemed to be a little longer then tripped out again.

Does the collective experience on this thread have any advice on this?. My concern now is that the pump is under powered and stuggling to pump against a 45m head of water containing a degree of sludge and I will have to pull the whole thing out to inspect it, cutting up the pipe as I go, then possibly replace the pump, but not know if this is correct until the whole thing is back in place and I try again.

Thanks in advance

You probably have a check valve (one way valve) installed just outside of the top of the casing. I would take the check valve out and allow the water in the pipe to backwash back down through the pump. Maybe even force more water down the pipe. That should clear any debris from the screen on the pump. To pull the pump a meter or so higher in the casing would also be a good idea. You should have some information regarding the pump capacity. Check to see if it is rated to push water the 45 meters. That is a deep well.

The inner 2" pipe is PVC (please take note Khonwan, I think it's PVC all the way with PVC glued unions/connectors) joined by a threaded union to a metal flange plate which then has an elbow then another union onto my PVC pipe distribution system leading to the filters. Tonight I disconnected the top union, pulled the whole thing up about half a meter to acheive an easy resting place. I then angled a watering can over the discharge nozzle such that the water spout was pointing back down the 6" jacket.

I then ran the pump, to fill the can and then shoot the water back down the jacket. Same result - the protection circuit kept tripping about every 5 mins, but the water was relatively clear. I repeated this about 10 times to see if the pipe would show any signs of filling - it didn't. I also pulled the pump up and down a few times to see if I could "flush" the intake guard. - no real change.

There is no obvious sign of a check valve at the top end fittings on the pipe header.

The box of trickery is labelled as follows:

Sun motor submersible motorcontrol

Over current Protection

Pump = 1.0 hp

Any further clues / ideas

cheers

Running the pump and putting the water back down the casing will not back flush the pump. You have to have the power to the pump shut off. The smaller pipe (outlet) coming out of the casing needs to be disconnected and if there is no check valve at the pump, the water will flow back down the outlet pipe through the pump. If the water in the pipe coming out of the pump does not drain down that means the check valve is on the pump and you will not be able to back flush from the top of the casing. You will then have to pull the pump to inspect it. A good installation will have a stainless cable attached to the pump and it will be attached to the top of the casing. Sometimes they save a few baht and use plastic or nylon rope. Unfortunately it usually works better to have the check valve on the pump itself. That means you can't flush the pump without pulling it out. Sometimes they call it a foot valve because it is at the bottom of the well. The cable or rope is a safety measure in case the pipe breaks or you accidently drop the pump. The power cable is NOT a good way to pull the pump out.

[Lickey]

Sinom, as i mentioned before, Chownah came in with the maths and his post is totaly believable, I posted before about intermitant pumping and cavitation, about 1.5 riser going into 200+ mtrs of 2" to feed sprinklers for crop irrigation, he put me right ... it was low water, not suprising after 8/9 hours pumping a day since last september!!the pump was a 1hp O&K with no control box, just on/off switch.

From what youve told us, even with the delivery pipe cut and putting water back down the bore, it still cuts out! so do you have any limit switches in your swiming pool ect?

Seriously, before going through the sweat and toil of pulling pump up, check the wireing in control box, the thai leccy who done mine didnt have a clue where the wires went!! so i done it myself, mainly because the colours were in english, not thai, A good idea would be to check wireing in box, mine has 5 contacts, LI L2 is main power in, then RED YELLOW BLUE or BLACK, although 1 wire from pump was white, put this in the Y connection, the other 2 were red and black or blue, sorry, im terrible with colours, but im sure you get the idea.

I remembered to bring my pump book from farm for new franklin pump today, and have been looking at the trouble-shooting page, wish i had a scanner!!

Under overload protecter trips when motor is running,it states to check --line voltage make sure that this is within +- 10% of plated voltage on pump while motor is running,

Also make sure control box is out of direct sunlight

Wire size to small, There is a lot of charts about wire size in book, I dont really understand them , but if the wireing that came with the pump reaches to control box, all should be ok, if extended and isnt compatible perhaps this is where the resistance and heat up of control cuts off motor?

One more point Sinom, didnt you get some kind of water garautee with the work done? usally, they want to run pump for 24 hrs and then garauntee water for 1 year, if not, they should come back and rebore! it seems they installed everything, electrics as well, so if you dont have any luck with the above checks, call them back!!

[xerostar]

I had a pump with similar symptoms.

It would pump really great for a few minutes and then the water stopped.

The ground was sandy clay.

Water was not soaking back into the well fast enough to keep up with the pump.

As somebody said earlier in this thread, submersible pumps don't like to run

dry for too long, thus the thermal protection cuts in.

We fixed the problem by sinking another bore with a larger diameter outer slotted casing.

This allowed more water to seap through to the pump.

The plastic bore casings we buy here in Perth OZ have thousands of very fine

horizontal slots cut at right angles to the pipe. Do they have the same stuff in LOS?

Do you use what we call a spear?

There are different types available usually about 2 or 3 metres long Sealed at one end.

The walls are covered in fine stainless steel mesh. A foot valve is

usually placed at the top end and a heavy duty PVC draw pipe glued into that.

We nearly lost a spear when we used the inner PVC pipe to pull the spear out.

One of the glued couplings came unstuck half way down the bore hole.

Sand had risen around the spear and had a really tight hold.

I made a sort of heavy harpoon (with barbs) out of angle iron with a heavy duty

nylon rope attached. We dropped that down the hole and it stuck into the 2 inch pipe.

We used the block and tackle to very slowly and

carefully pull the whole lot out. The barbs had wedged themselves into the inside of the PVC.

[RasiMike]

^ Palm, I think I paid 70-80,000 for mine, 6" hole, 2 hp pump can do about 10,000 l/hr all the fittings ect, it's about 60m but this is a few years ago.

Rasi mike, thats a remarkable low price, you can't buy a pump for that

Hi, RC. The pump and pumbing was extra (did it myself for 3500 Baht). I wasn't sure at the time if I was getting a good deal for the boring/casing/spear, (new resident) but after reviewing this forum I am happy as a pig in ......

This was bore has been working well for us, although it isn't working on a commercial scale.

[palm]

My Thai project manager was just quoted 120,000 baht for:

9" bore-hole

up to 100m deep (they said 50-70m is probably what we'll end up needing)

including submersible pump and motor etc

screw-together tubing

10% deposit

40% on completion and working after a few weeks

remaining 50% after 12 months if everything is still ok

will take about 10 to 20 days to do unless they hit a ton of granite (same price, their hard luck)

Location is Phitsnulok. Seems quite a fair deal to me?

I have about 120 rai to supply, and new lakes to build/fill etc.

Well the borehole is finished and working great. In the end, they went down 142 METRES!

They came with a huge truck with the big drill platform on the back, and with 11 staff and worked for about 20 hrs a day, for about 5 days.

We have a 1.5 HP motor etc and we are getting fresh, crystal-clear water.

We had to get a license at the local authority place, as we are pumping on a 'commercial scale', but it was only about 7,000 baht or something.

Edited April 12, 2007 by palm

[sinom]

Sinom, as i mentioned before, Chownah came in with the maths and his post is totaly believable, I posted before about intermitant pumping and cavitation, about 1.5 riser going into 200+ mtrs of 2" to feed sprinklers for crop irrigation, he put me right ... it was low water, not suprising after 8/9 hours pumping a day since last september!!the pump was a 1hp O&K with no control box, just on/off switch.

From what youve told us, even with the delivery pipe cut and putting water back down the bore, it still cuts out! so do you have any limit switches in your swiming pool ect?

Seriously, before going through the sweat and toil of pulling pump up, check the wireing in control box, the thai leccy who done mine didnt have a clue where the wires went!! so i done it myself, mainly because the colours were in english, not thai, A good idea would be to check wireing in box, mine has 5 contacts, LI L2 is main power in, then RED YELLOW BLUE or BLACK, although 1 wire from pump was white, put this in the Y connection, the other 2 were red and black or blue, sorry, im terrible with colours, but im sure you get the idea.

I remembered to bring my pump book from farm for new franklin pump today, and have been looking at the trouble-shooting page, wish i had a scanner!!

Under overload protecter trips when motor is running,it states to check --line voltage make sure that this is within +- 10% of plated voltage on pump while motor is running,

Also make sure control box is out of direct sunlight

Wire size to small, There is a lot of charts about wire size in book, I dont really understand them , but if the wireing that came with the pump reaches to control box, all should be ok, if extended and isnt compatible perhaps this is where the resistance and heat up of control cuts off motor?

One more point Sinom, didnt you get some kind of water garautee with the work done? usally, they want to run pump for 24 hrs and then garauntee water for 1 year, if not, they should come back and rebore! it seems they installed everything, electrics as well, so if you dont have any luck with the above checks, call them back!!

AN UPDATE ............

been away on business for a few days and had a bit of a ponder on the problem, managed to download a Franklin pump maintenance manual to get a better understanding (I think my pump is a Franklin copy but all of the circuitry looks the same).

I agree with whoever said earlier that it was not anything to do with the pump control box. I have a level control system on my underground water storage tank to stop/start the sub-pump and to run a backup supply of city water in case of pump failure. I have all the drawings for the control panel for this but failed to pick up that they have added an over current protection relay in this box. The relay has a max trip setting of 6.5 A

Sooooooooo! I put a meter on my pump power supply and measured that it runs normally at about 5.2A (my guess is this is a little bit high due to the pump having to work hard to get up the 45m head, as mentioned earlier by Chownah). The measured current did not pass the trip threshold of 6.5A, but it did trip! My guess is that the accuracy of trip setting on the relay is +/- approx 10% and this is causing the problems.

Soooooooooo! I bypassed the trip relay and can quite happily run the pump for over an hour (or more) without problem. The current stays pretty stable at about 5.2 - 5.5A. My thinking is that if I was just running the pump on a manual on/off control it would not have had this protection relay anyway.

I shall get back in touch with the supplier of the level control panel and get a higher rated protection relay installed (or maybe just removed)

I now have underground (free) water ..... Hoorah !

Thanks for all of your assistance

Sinom

[Lickey]

Glad you got it sorted Sinom, had to be something simple electrical wise, new pumps are designed to last, bet youve glad you never pulled it out,

Hope your adjustment to near free water has given your sonkram celebrations a boost, cheers,

[raylo]

For those Americans who are puzzled about what a bore hole is and what a well is.....in the US where I come from, a well is a hole in the ground that you make to pump water out of. If you drill a hole in the ground to do this then we call it a "drilled well" and if you use a digger to do this (clam shell, specially adapted back hoe, or a shovel and muscle) then its called a "dug well".....or course if you dig a pond to get water that's not considered a well at all and I won't try to define the difference between a "dug well" and a "dug pond"....but its usually obvious when you see them side by side!!!! Anyway, a "bore hole" is a "drilled well" in American lingo.

MaizeFarmer's talk was really good for drilling wells (makeing bore holes) when the water in your area is very deep...but in some areas (like where I live in the North) it is relatively near the surface and the conditions do not require a lot of the equipment and cautions he mentions. Before describing how my well in Thailand was drilled I want to say that I had a well drilled in the US and we did have one cable attached to the submersed pump but the pump itself was screwed onto the pipe that carried the water upward so hoisting the pump was actually done by lifting it by the pipe....and the one cable was the backup method......galvanized one inch pipe...very sturdy....the pipeing weighed more than the pump I think.

So...on to my Thai well experience. Where I live water can be reliably obtained in a seam of white sand that usually lies from 7 to 9 meters deep....but this seem of water bearing sand is pressurized somewhat so that when the well is drilled the water rises to about the ground water level as near as I can tell although I haven't monitored this throughout the year. Because of this we do not have a submersible pump....just a straight centrifugal pump mounted topside and pumping out of a one inch pvc pipe that goes down about 9.5 metres with a check valve (one way valve) on the bottom........................................

Question Chownah - My "well" - please correct my assumption as to that is what it is -

It's approx 9 m deep, concret pipe approx 450mm in diameter and I have 3 of them on 2 properties.

[Farma]

It looks like the father in law got lucky judging by some of the prices and depths mentioned here.

He had a borehole drilled a month back and used large blue pipe as a liner. This is the standard method in his village.

The water table must have been high as the hole cost 800 Baht to drill and another 812 Baht for the pipe. There's a smaller pipe in the borehole that allows water to be drawn (pumped) by hand until he gets a permanent power supply to run a pump.

[sattahip]

This is a great thread. Thanks to all who have contributed.

I have just had drilled in Baan Amphur, Sattahip a bore for my new home.

2 days drilling yielded 5000 litres per hour salt and iron free fresh water at a depth of 45 metres from a crushed granite stratum.

Cost was B24,000 if no result and Baht80,000 if successful including submersible pump (Franklin). PVC was used and I noted that the base pipes were as described by an Australian contributor with integral slits and joints were glue sealed-no screws. Thanks to someone else I insisted on a stainless steel wire to the pump.

I am descibing my building experiences more fully in a forum the moderator moved it to called Forum > Business in Thailand, Jobs in Thailand > Real Estate, housing, house and land ownership-

Again thanks to all

[johnandtai]

Hi. We are trying to find out the best 2 HP submersible pump available in Thailand. Any information would be appreciated.

John in Chiang Mai

[Lickey]

John, try to find a Franklin, its a submersible made in the USA and good for depths of 150 mtrs, it will cost you about 20,000 bht, plus the borehore ect, but some Franklin pumps have been submerged for 8/10 years with no problems, hope this helps you, rgds, lickey.

[Alf Witt]

Can anybody advise upon the viability and practicalities of drilling for fresh water on a slope about 30 degrees leading down to seawater? Thanks.

[Alf Witt]

Can anybody advise upon the viability and practicalities of drilling for fresh water on a slope about 30 degrees leading down to seawater? Thanks.

???

[xerostar]

We used to live in a seaside town and had a bore which supplied brackish water

that was not nice to drink but was OK for the garden.

We were about 200 metres from the beach.

I suppose it all depends on the local geology and how far your borehole is from the seawater.

Another factor is the depth. Sometimes fresh water can be found deeper down.

If there are other people living nearby, you'd need to ask around to see if anyone else has

had success with a bore.

If the need is very great, I'd just go ahead and drill and see what you can get.

[Alf Witt]

Thanks Xerostar,

We are isolated so it is an unknown locally.

Any ideas about the effect of the hillside? I know water runs down the hill at ground level but what about underground? Does the nursery rhyme about Jack and Jill have any basis in reality?