Water Well - Needs 'low Water Sensor' - Where To Get One?

[maidu]

I've got 3 properties with 3 water systems, all with submersible pumps. Flows are good but not great, so after a few minutes of pumping, the pumps start gurgling air, as the water recovery rates are not so good. I've seen online that a very few dealers ww have 'low water sensors' for sale. I saw one for sale for $41, not counting shipping - from the US.

I reside in Chiang Rai, and have been to the major pump dealers here - and only one had something that looked like it might work: though it had a little water hose coming out of it.

The item I want attaches just above the submersible pump, and simply cuts the power when water falls below that level. Ideally, it would have a delay, which turns the power back on in 10 minutes or so. Anyone know of something that might work?

I've even done some sketches - towards designing one - to fabricate. Since no such item appears to be for sale in Thailand, perhaps the marketplace would support such an item. The alternative is tens of thousands of water pumps burning out each year. Which makes better sense?

[Mosha]

I worked in the chemical industry, and this technology is wide spread. So if not here, a search back home maybe. All you need to do after all is switch of the live feed to the pump at low level.

[sandgroper3]

its called a float switch if you cannot buy one for your pump ,maybe you can adapt one from a marine bilge system

[VocalNeal]

Any shop that sells water tanks will have a free floating or cable mounted "float switch" they are standard on most water tanks. Or at least the ones I have had experience with. Cable switch needs a bit more working head than a fixed one about 100mm minimum difference. Technical term is "differencial". It depends on how deep the water in your well is.

OR

In the picture above #3 needs to be 100mm or more.

If you are handy and the water level in the well is not deep enough for a free floating switch you can improvise with a couple of steel rods, a 12v wall mounted power supply and a 12v Horn relay from a car.

Edited April 14, 2013 by VocalNeal

[Lickey]

As Vocal describes above, its an electric cut out to the pump when the level is low and on when at a predermined height,

Thai name is a Luk Loy, around 550/600 bht from any good water,house irrigation suppliers,

[jbrain]

Every hardware store alike home pro, global house have the adjustable ones with two counterweights at about 400 Baht. If you want a delay install a timer switch that get's activated when the required level has been reached

[Longtooth]

Or, you could have a 60 meter deep 4" diameters well drilled in Chiangrai for about 60,000 baht by one of about 3 different guys here that have made a little 4" drill rig trailor with it's own engine. Or you could buy a control box at one of many pump shops that has the time delay relay and shutdown already built in. They normally use a "low flow" switch, as opposed to a "low level" switch. I had to tweak on my "low flow" switch's adjustment screws to only switch at the lowest flow rate (mine is installed right above the well hole), then no problems for 5 years now. Or you could buy one of those tiny submersible (I'm asuming you're talking the ones that go down a bored hole, and not the "cellar pump") pumps. The smaller the pump, the lower the rate, and the water inflow can better keep up with the outflow. If you're talking a shallow well, it would be better quality water if you drilled a deeper one, also. (If you want to spend the money.)

[maidu]

Maybe I didn't make my situation clear enough. I know all about float switches in holding tanks. I've bought a half dozen over the years. The latest one went bad because of a very poor solder on one of the inside leads ('made in Italy').

What I seek is a low water level sensor which gets attached just above the submersible pump.

Here's one of the very few mentioned online. It's made by the German company Lorentz. I have it for one of my pumps (solar) and it works fine. However, the Lorentz one operates via the control box which comes with their pump, not independently.

I thought of designing/building one, but don't quite have the skills and materials to do so. If anyone reading this wants to take a stab at it with me, let me know. I have some sketches. It could be like Mr. Rolls and Mr. Royce collaborating . The latest idea has one sensor just above the subm. pump and another a few feet higher. It operates using a 2 switch / 3 pole idea. The lower switch turning off the power, and the higher one turning it on again.

The post above presents an interesting idea which I had thought of - but haven't yet implemented: a smaller pump which won't suck out the water as fast. my situation has about 40 meters of 'head', so not sure whether an AC submersible will pump that high - if it's less than 3/4 horse. Alternatively, I plan to switch to DC pump (I've gone DC before) which pumps higher with lower amps, though perhaps not as much volume. Trouble with DC, for me, is thieves steal the solar panels. I could build a 4 meter high anchor fence topped with barbed wire around the panels and/or have attack-trained dogs nearby, ....but that's not my style.

Edited April 15, 2013 by maidu

[VocalNeal]

Not having been out to the shops Omron 61F-G2P Automatic Drainage Control available from Omron Thailand.

http://www.omron-ap.co.th/product_info/61F-GPN-V50/index.asp

At least $250 each.

You don't need "electrodes" just connect the wires to two hose clamps around the plastic outlet pipe. Like most it only switches 3A so you need to connect it in series with the on/ off switch which goes to the pump relay.

OR Have you visited Thai Watsadu in Chiang Mai or Global House? I'm sure this is not a problem only for us visitors.

EDIT: Modified " you can improvise with a standard two prong house plug, a 12v wall mounted power supply and a 12v Horn relay from a car".

Edited April 15, 2013 by VocalNeal

[jackflash]

Clipsal in Australia make various models:

http://updates.clipsal.com/clipsalonline/Files/Brochures/I0000102.pdf

many other types available, even wireless ones:

http://www.dhgate.com/wholesale/liquid+level+float+switch.html

Edited April 15, 2013 by jackflash

[Boksida]

Maidu, I have previously installed these after buying the control boxes in Bangkok. One type had an electrode set below the pump (always submerged), one above the pump (low level cutoff) and one higher up in the well below static water level (restart after recovery). Lately the Franklin PumpTec (or similar) has been more popular due to easier installation. It is an above ground box that senses pump speed increase when pump starts to cavitate and has an adjustable timer to allow restart. None of the other types suggested in this thread are suitable for deepwell usage and I assume this is your application?

If you are interested and can't find a supplier, let me know and I will check some of the Bangkok suppliers for availability. They are not very big and could be sent to you via tour bus. The supplier would need to know motor specs.

[gimbo2]

Before I start DONT jump down my throat for what I am about to say.

To Maidu,

I read your 1st question and can suggest the following. I am from a farming family with 300 years of farming so I cut my teeth on pumps & wells. I have spent the last 40 years as a "Mech. Design Engineer".

That over with I would like to ask you:

how deep are your wells?

When did you last have them cleaned out?

What are liners made of?

What dia. are the liners?

What dia are the bore holes?

What material did you fill between the liner and bore holes.

Yes I know Im going back to the basics but once we know this there may well be an easy way to over come your problem, I have a number of farms over here in the Chiang Mai area ALL with deep well pumps.

Rgds

Grumps

e&oe

[Secondmouse]

its called a float switch if you cannot buy one for your pump ,maybe you can adapt one from a marine bilge system

I agree with sandgroper3,

I've maintained many marine water systems over the past 25 years and I would suggest using an 'enclosed' float switch more commonly is used on boats for the 'shower cubicles'.

The water enters the "shoe-box like" unit and is filtered before it reaches the float-switch, (normally to stop hair clogging up the system ).

I would also incorporate a relay to power the main 'irrigation' (?) pump.

When the water level in the unit is sufficient to raise the float switch, the contact is made to power the relay which in turn will switch on the main pump, as soon as the primary water supply runs low, the float switch falls therefore disconnecting the relay...ditto to main pump.

'Rule' are one of many companies that make bilge pumps and many others can also be viewed at 'WestMarine.com' and are widely available in SE Asia by many makers.

[maidu]

Before I start DONT jump down my throat for what I am about to say.

To Maidu,

I read your 1st question and can suggest the following. I am from a farming family with 300 years of farming so I cut my teeth on pumps & wells. I have spent the last 40 years as a "Mech. Design Engineer".

That over with I would like to ask you:

how deep are your wells?

When did you last have them cleaned out?

What are liners made of?

What dia. are the liners?

What dia are the bore holes?

What material did you fill between the liner and bore holes.

Yes I know Im going back to the basics but once we know this there may well be an easy way to over come your problem, I have a number of farms over here in the Chiang Mai area ALL with deep well pumps.

Rgds

Grumps

e&oe

The wells were put in by inexperienced and/or inept well drillers. I tried to be on-hand as often as possible, but wasn't at the scene when the well casings were put in, and I think they were put in unprofessionally - but I don't know for sure. A well I had put in in California (before coming to Thailand) the contractor banged the 4" pvc casings with a hatchet (for the lowest ones) before he installed them - in order to crack the casings to enable ground water to enter. If a video were taken of the Thai contractor putting in the casings, then I'm sure a western expert, like Grumps, would have found several things were awry. I found out soon after the casings were put in, at least two things were done wrong, but it's too much to articulate about here and now.

Suffice to say, for my current predicatment, that I've shortened the float valve wire, so the variance between full (turn off pump) and low (turn on pump) is smaller. Hopefully that will lessen the incidence of having to replace pumps. Currently, I've been replacing pumps (that have burned out) every year or two (in 3 wells). Now, am hoping the individual pumps will last at least several years before burning out. In the meantime, I'll keep looking for some 3-wire 'low water sensors' as alluded to by Boksida in post #12.

[gimbo2]

Hello Maidu,

Thank you for your reply.

However I note that you did not or were not able to answer any of my questions.

Your idea of float switches etc is I am sorry to say a "Bandage" to a problem that is NOT going to go away.

Float switches on deep well pumps is a "No NO" . Deep well (Including Sub type) are NOT designed for short ON/OFF cycles. They will burn out.

I have "Sub Pumps" here that have been down the well for 10 years with no problems and still pumping with new pump flow rates.

Our pumps on all our farms pump from 2500 liters to 5000 liters a time.

If you are unwilling to repair or what ever your wells then I feel the best thing for you to do is to drop a small pump down the well so it will run longer.

But at the end of the day its your farm & pump.

[Canada]

Before I start DONT jump down my throat for what I am about to say.

To Maidu,

I read your 1st question and can suggest the following. I am from a farming family with 300 years of farming so I cut my teeth on pumps & wells. I have spent the last 40 years as a "Mech. Design Engineer".

That over with I would like to ask you:

how deep are your wells?

When did you last have them cleaned out?

What are liners made of?

What dia. are the liners?

What dia are the bore holes?

What material did you fill between the liner and bore holes.

Yes I know Im going back to the basics but once we know this there may well be an easy way to over come your problem, I have a number of farms over here in the Chiang Mai area ALL with deep well pumps.

Rgds

Grumps

e&oe

The wells were put in by inexperienced and/or inept well drillers. I tried to be on-hand as often as possible, but wasn't at the scene when the well casings were put in, and I think they were put in unprofessionally - but I don't know for sure. A well I had put in in California (before coming to Thailand) the contractor banged the 4" pvc casings with a hatchet (for the lowest ones) before he installed them - in order to crack the casings to enable ground water to enter. If a video were taken of the Thai contractor putting in the casings, then I'm sure a western expert, like Grumps, would have found several things were awry. I found out soon after the casings were put in, at least two things were done wrong, but it's too much to articulate about here and now.

Suffice to say, for my current predicatment, that I've shortened the float valve wire, so the variance between full (turn off pump) and low (turn on pump) is smaller. Hopefully that will lessen the incidence of having to replace pumps. Currently, I've been replacing pumps (that have burned out) every year or two (in 3 wells). Now, am hoping the individual pumps will last at least several years before burning out. In the meantime, I'll keep looking for some 3-wire 'low water sensors' as alluded to by Boksida in post #12.

I think that you will find that no wells here are properly cased or very few anyways. I have drilled 7 so far this year. 4 "small holes" and 3 large holes. Non were done properly in terms of being cased properly. They will case the top 4-8 meters or will case till rock level. None of the casings were split or cut and none had fill between the casing and the wall of the hole. I think you'd be pretty hard pressed to get a well drilled to these specs.

As far as your quest....Distributors for sub pumps should offer for sale what you are looking for at about 7000 baht. Reps for Mitsubishi were at the distributor where I shop (which is in bumfucknowhere) and informed me of and tried to sell me the controller that will protect the pump from low flow incidence. Keep looking.

Cheers

[gimbo2]

Hi Canada,

Sorry have to disagree with you 100%. As I said I am from "Farming Stock" and have an 'Engineering Back Ground"

I have many many wells up here in CNX and I knew "Exactly" what I wanted and most important "How I wanted It Done"

All my wells are 100M plus deep, ALL cased (Lined), etc. Its NOT PhD material.

Haven't had ANY trouble with PUMPS or WELLS. Never even had to clean them out, haven't even lifted a motor & pump out in at least 7 years!!!!!

It seems the problem here is someone with no real knowledge of farming or in particular wells etc has gone about looking for water without asking the right people the proper way of doing so.

Welcome to call me on my mobile if you want some advice on this matter on 0911418611

[maidu]

Thanks for the responses. Much to ponder. I had several wells put in - in northern California, and have had several put in here in northern Thailand. I agree that, the more professionalism you pay for, the more likely you'll get a quality job.

[Packdee]

Hello Maidu,

I think it is Flow switch.

The switch is attached above the submersible pump, and cuts the power when water stop flowing.

You can buy from the waterpump dealers in Chiang Rai.

The key word for searching in internet is "ขาย Flow switch"

And your water well needs to be cleaned.

The well digger will pull the pump up and use high air pressure to drive water up until the flow rate become good.

There is a word in Thai "wang ya = วางยา".

The medicine man does not prepare correct medicine for the patient.

He expect to come back again and again.

Edited April 16, 2013 by Packdee

[Canada]

Hi Canada,

Sorry have to disagree with you 100%. As I said I am from "Farming Stock" and have an 'Engineering Back Ground"

I have many many wells up here in CNX and I knew "Exactly" what I wanted and most important "How I wanted It Done"

All my wells are 100M plus deep, ALL cased (Lined), etc. Its NOT PhD material.

Haven't had ANY trouble with PUMPS or WELLS. Never even had to clean them out, haven't even lifted a motor & pump out in at least 7 years!!!!!

It seems the problem here is someone with no real knowledge of farming or in particular wells etc has gone about looking for water without asking the right people the proper way of doing so.

Welcome to call me on my mobile if you want some advice on this matter on 0911418611

Hi there,

Not really sure what part of my statement you disagree with. You may have some good deep wells that are cased from top to bottom and are filled between the casing and the hole, but I would say that that is an exception here, based on what I have seen.

In any case, I am curious about your wells. Price. How much did they cost? Bore diameter? casing diameter? and fill between the casing and bore? Who did them? Do you have the contact info still? Did you happen to build a water tower as well for any of the wells?

Any good reference material on water wells that you could point me to? I am not from farming stock, (but have a farm) and am not a mechanical engineer. So you are correct in your final statement. We have drilled 7 wells already and expect to drill a couple more...so they may as well be good ones.

[maidu]

Hello Maidu,

I think it is Flow switch.

The switch is attached above the submersible pump, and cuts the power when water stop flowing.

You can buy from the waterpump dealers in Chiang Rai.

The key word for searching in internet is "ขาย Flow switch"

And your water well needs to be cleaned.

The well digger will pull the pump up and use high air pressure to drive water up until the flow rate become good.

There is a word in Thai "wang ya = วางยา".

The medicine man does not prepare correct medicine for the patient.

He expect to come back again and again.

Thanks, I'll try that. As for 'getting water well cleaned' I had that done (and paid for), about 6 years after the well was put in. Just prior, I asked the well drilling co. whether they could do it or who they would recommend. They told me "Oh, we do that service FOR FREE, if you asked us within a year from when we first drilled the well." Those bastards. They might have had that written in tiny font somewhere, but they certainly didn't tell me when I was talking with them at the time the well was constructed. That's just one of several things they did badly. But how can you chastize a Thai company? They either don't hear you, or they get offended and angry, and cuss under their breath about how f*cked up farang are. Anything, but take responsibility for their mistakes and/or bad service.

[derekwyoung]

Hi

http://www.vellemanprojects.com make a liquid level controler,with three sensors, low middle and high. Flow switches are available through Sang Chai Meter CO .,Ltd Have a very wide range mostly at bangkok branch but next day service to branch at Lampon on the #11 road at the trafick lights diagonly opersite big C, dont know if there is a branch neerer you

[Quindalup]

If you know how long your pump will run without going dry, could you simply put a timer on the power feed to the pump. Some timers give you multiple selections in a day. You could run the pump for 15 minutes (or what ever suits) let it sit for a determined time then it will turn on again when wanted and so on.