Setting up a water tank / pump system help needed

[Kenny202]

We live in rural Thailand and our town water supply is very unreliable. We buy our drinking water cheaply so thats covered but use the town water for washing, showers etc. I was thinking of strengthening the old block / cement back toilet (roof / we don't use it anymore) and placing a 10000 or 15000L plastic water tank on top. Don't worry too much about the structure etc, I'll make sure thats ok. I could probably run a permanent hose up to the tank and fill manually (when town water is available and strong). Not sure if normal town water pressure will be enough to climb the 2 or 3 metres up to the top of the tank without a pump? And I'm hoping the natural fall from the tank would be enough pressure for showers, reasonable hose pressure etc. Bare in mind our normal pressure is at best just enough to operate the instant wall hot water shower...but a lot of the time not or non existent.

If I place the tank up in the position I am thinking about the bottom of the tank will be around a metre above the tap / shower outlets. So when full the

water / top of the tank will be around 2.5 metres above the outlets and fairly close to the house.

a) is 2+ metres high enough fall to get a reasonable pressure out of a tall thin 15000 litre tank?

Is it likely the town water when strong will climb 2 or 3 meters up to the top of the tank to manually fill by hose or will a pump be required?

I guess I could try this one day when the water is strong standing on a ladder with the hose up a few metres?

c) My plan would be too introduce the tank water into out pipe by a T junction. So would have the option of introducing the tank water into our home pipes along with the town water or maybe have a cock on the tank side and only have the tank water come into the system when we want. Maybe a one way valve on the tank outlet so water can only come out, not go back into the tank from the town water supply.Is it ok to mix the two supplies together or will this have ill effects?

d) Is this the way to go about it or should I be looking at another method. As quite often we have no water, a simple pump boost system wont be enough. We need some sort of reserve. The more simple technically wise a system the better

Edited January 28, 2015 by Kenny202

[Rooo]

Moved to DIY Forum.

[KhunBENQ]

15000 ??? In words fifteenthousand liters ???

15 cubic meters?

Thats a hell of a tank! Never seen a water tank that big.

You definitely mixed up the numbers I guess?

A small tiny tank is 500 l, medium 1000 l, big 2000 l and up.

We need about 11000 l a month(!) for a family of four (one child).

a ) 2 to 3 m high enough for shower (hot water) or tap? NO!

b ) 2 to 3m low enough for communal water to climb up to the tank? YES! Very unlikely that the pressure is THAT low. But OK, test it,

c ) plan to have the possibily to change between communal water and tank water (with and without pump engaged: pump bypassed, tank outflow closed)

From a ): you need a pump.

2 to 3m is 0.2 to 0.3 bar. Way to low for any comfortable water supply.

For decent shower, supplying a modern washing machine you will need a pump.

We have 2000 l on an ~10 m tower,

It was not my idea to have the tower, as it is quite useless.

Just good to have water on power outage, when the pump can not work.

A 500 l tank as a buffer is big enough for a small household.

For your use I would not put it on any sort of tower, just the outflow higher than the intake of the pump.

Edited January 28, 2015 by KhunBENQ

[lopburi3]

As said you must have an extra zero on the tank size - and you may not have enough pressure to even fill tank above normal tank height but having above round a couple of meters is not going to give you any water pressure - as said you will need a pump from tank to house. You should have water to top of tank and have a float turn it on/off (every plumbing shop will have)

[pigeonjake]

if hes going to start putting inline pumps in he might as well go the whole hog and have a bore hole drilled, and an auto pump,

we have this for the house and like many i dont have a tank at all, just the bore hole with the pump on top conected to the house, been like that for years no problems,

after all thats what auto pumps are for, i can never understand why some have big water towers as well as auto pumps,? i could be wrong but like i say our as been like this for years and no trouble,

its about 5k to drill the bore hole and another 5, or 6 for the pump

[NeverSure]

Water is really heavy. Be sure to calculate the volume in that tank and figure the weight before you consider putting it on top of some old thing.

No you won't get the pressure you need at that height. You'll need a pump so no need to elevate it at all.

I'm with Jake, above. Make it simple, clean, and do it just once. I'll bet Jake's description is overall cheaper, too.

[chickenslegs]

This is a diagram posted on TV a while back (can't remember who posted it)...

Tank can be at ground level, underground, (or raised, if city pressure is sufficient).

200W-300W pump should give plenty of flow for showers etc.

Edited January 28, 2015 by chickenslegs

[kannot]

if hes going to start putting inline pumps in he might as well go the whole hog and have a bore hole drilled, and an auto pump,

we have this for the house and like many i dont have a tank at all, just the bore hole with the pump on top conected to the house, been like that for years no problems,

after all thats what auto pumps are for, i can never understand why some have big water towers as well as auto pumps,? i could be wrong but like i say our as been like this for years and no trouble,

its about 5k to drill the bore hole and another 5, or 6 for the pump

more like 180k to bore, thats down to 85 metres in Pranburi.

[scooterboy]

Yep - Chickenlegs' attached diagram example is the way to go.

Might be Crossy's original pic, not sure - but I used the same pic to install my water system - works perfect!

[crickets]

Defintly get a pump. Gravity fed hot water sucks. Dont waste your time putting it on the roof and i doubt the pressure will be enough to fill. Are u low on cash? Pumps arent expensive and u can get a flow if around 20ltrs a minute which is a damn good shower compared to gravity fed 5ltr minute. If doing install yourself be sure to put a non return valve on before your pump and a switch cock after it if u dont want to use the tank.

[Gentmartin]

I also used this brilliant diagram i was sent way back and its simple and perfect. Follow it my friend to the letter.

..and just to add an FYI, Id suggest the tank on the ground as it will fill easier. The reason the pump is where it is in that diagram is because youre not allowed to use a pump to draw watwe from the mains i believe :-).

[jacko45k]

This is a diagram posted on TV a while back (can't remember who posted it)...

Tank can be at ground level, underground, (or raised, if city pressure is sufficient).

200W-300W pump should give plenty of flow for showers etc.

That diagram is probably very much like mine except I have a check valve in the lower line and leave the hand valve open, this allows the incoming city supply to bypass the pump/tank. Automatic water supply when no electricity too!

I suppose the T connection could go after your filter, I don't have an incomer filter. (Future thought).

Often the mains pressure is sufficient that the pump will not need to run and I save electricity.

(May not be the case in many locales)

I even turn the pump off altogether, that way I am 'aware' if my mains water supply is off (often the case), and I don't start watering the garden and empty my tank. Of course this might mean the odd trip out to the tank where the switch is in my undies, and armed with a flashlight.

Edited January 29, 2015 by jacko45k

[inkorat]

If the water pressure from the village is low it may be best for you to put your storage tank under the ground so you are 100% sure you will get water into your tank, if there is water in the main supply line. In many areas in Thailand, the government supply lines are undersized and you end up competing with others for a limited amount of water. A tank under the ground will get water, even when there is not enough pressure to lift the water into the neighbors tanks that are above the ground.

You will then need a pump to move the water into your house and maintain the water pressure desired.

As a rough calculation each 60 cm of water level height above the outlet height will provide you with approximately 1 psi of water pressure. So 2 meters height is only 3.3 psi of water pressure or roughly 0.22 bar as stated above.

You should not connect a water pump directly to the government water supply line, since it may not have water in it and your pump could burn out or be damaged. It could also create a vacum in the supply line and suck dirty water into the pipe through any breaks or cracks in the line.

Good Luck..

[recycler]

When relying on a pump and underground tank, make sure you always have some water in a barrel spare to finish your shower when power fails.

It always happens when you can't open your eyes with your head covered in shampoo ;-)

[Gsxrnz]

I also used this brilliant diagram i was sent way back and its simple and perfect. Follow it my friend to the letter.

..and just to add an FYI, Id suggest the tank on the ground as it will fill easier. The reason the pump is where it is in that diagram is because youre not allowed to use a pump to draw watwe from the mains i believe :-).

Yep, the diagram is simple and is what's done in most installations.

But despite the fact that it's illegal to pump water directly from the mains, I've added an additional couple of valves that allow me to pump from the mains directly into the tank.

Occasionally we get low pressure from the mains that won't climb the 2 metres to the tank inlet but will have a head of maybe 500mm. I just flick the valves and fill the tank, and then revert.

Obviously not necessary if your tank is underground.

[SOUTHERNSTAR]

if hes going to start putting inline pumps in he might as well go the whole hog and have a bore hole drilled, and an auto pump,

we have this for the house and like many i dont have a tank at all, just the bore hole with the pump on top conected to the house, been like that for years no problems,

after all thats what auto pumps are for, i can never understand why some have big water towers as well as auto pumps,? i could be wrong but like i say our as been like this for years and no trouble,

its about 5k to drill the bore hole and another 5, or 6 for the pump

Where can you drill a borehole for B 5000? Are you talking about a borehole or a well ? Depending on the dept a borehole could be B 200 000 plus.

But I agree keep it simple. According to me two ways for the communual water. The first is an above ground tank, with the potential problem that at certain times the pressure of the comunual water may be to low to fill it. The second option (which most Thai's in our area use) is to have a below ground tank. The below ground tank doesn't need the same pressure to refill as the above ground tank and is easy to build, but you need a pump to have water pressure in the house. The borehole or well is an option but I would first talk to people in the area to find out how deep the water are and the quality of the water. Our borehole and equipment costed B 170 000 and my estimation on a well would be B 15 000 (depending on your pump, the dept of the well and excluding storage).

Good luck.

[Dumbastheycome]

Ground level tank with a ball float. Small pressure pump fed from tank with a float switch set to cut off power to pump if tank level too low. . Draw back is in the event of a power cut. Alternative is to go with same but pump feeding into a second elevated tank as iin diagrams already posted. That gets around the issue of pumping direct from mains. The elevated tank does not need to be large volume but at least 4 up. The ground level tank can be as big as you want.

Overnight pressure is usually sufficient to keep up with demand.

[ChiangmaiRob]

With the bottom of the tank at about 2.5m above your outlet, this will give you 3.5psi of pressure at your outlet. As your tank fills, that pressure will increase and if your tank is 2.5m high and full, that will give you another 3.5psi making it 7psi at your outlet. This might be enough to run a shower heater but I'm not sure but remember, as your water level drops, your pressure at the outlet decreases. The size of your water pipes should be considered as well, as the smaller the pipes, the less the deliverable volume.

A simple calculation to work out the pressure is H (water height in feet) x 8.3 (weight of water in pounds per gallon) x 0.052 and this will give your water pressure in psi. If your using meters for your height, just multiply your answer by 3.281. The minimum required pressure to run your electric shower should be on the box so check that out first before you decide how high to put your tank. In the end you may just have to fit a pump from your tank. Good luck with it anyway.

[Jedsada3]

Hello,

As said above, a maximum 2000l tank will be sufficient.

A very important thing you should know : ALWAYS use water from the tank and bypass it ONLY if there is no electrical supply!

As long as there is flow in the tank (from taking out and filling in) the water will remain "alive". If there is no flow, it will "die" fast because of the temperature and a lot of bacteria will find their home in your thank bringing smell and other unpleasant drawbacks

When building your system, don't try to save money on valves. It doesn't cost that much and can make you save a lot of troubles when something happens I used "quick connectors" before and after pump, thank and filters. It costs some more bahts but you will be thankful you have them the day you will have to remove pump, filter or change thank.

I build my "system" near the house in a accessible shadow open place with light. I can hear if the pump runs smooth and if there is a leakeage I hear it too (the pump runs and stops even if there is no consumption.

I check it every month for leakage and dirt.

Oh yes! Don't choose a too big pump. The old pipes might not support the high pressure...

[Crossy]

Yeah, I think that was my original diagram from wayyy back, evidently I should have charged royalties

[pigeonjake]

if hes going to start putting inline pumps in he might as well go the whole hog and have a bore hole drilled, and an auto pump,

we have this for the house and like many i dont have a tank at all, just the bore hole with the pump on top conected to the house, been like that for years no problems,

after all thats what auto pumps are for, i can never understand why some have big water towers as well as auto pumps,? i could be wrong but like i say our as been like this for years and no trouble,

its about 5k to drill the bore hole and another 5, or 6 for the pump

Where can you drill a borehole for B 5000? Are you talking about a borehole or a well ? Depending on the dept a borehole could be B 200 000 plus.

But I agree keep it simple. According to me two ways for the communual water. The first is an above ground tank, with the potential problem that at certain times the pressure of the comunual water may be to low to fill it. The second option (which most Thai's in our area use) is to have a below ground tank. The below ground tank doesn't need the same pressure to refill as the above ground tank and is easy to build, but you need a pump to have water pressure in the house. The borehole or well is an option but I would first talk to people in the area to find out how deep the water are and the quality of the water. Our borehole and equipment costed B 170 000 and my estimation on a well would be B 15 000 (depending on your pump, the dept of the well and excluding storage).

Good luck.

i live in a village just outside wangnamyen,

and to drill a bore hole 18mtrs deep 2 inch diamiter was just over 5k,

cab i ask how many bore holes you have?

ive got 3 2 for the house and one for the pigs,

and an auto pump is 5 to 6 k,

its a 2 inch bore with a 1 inch suction pipe to the pump,

ok, this is what ive got and been good for years,, this is the thing with thai visa nowadays you post what youve got or done from experience and get shot down,

have fun with yur tanks, dont forget a qube of water is a ton

[KhunBENQ]

don't try to save money on valves. It doesn't cost that much and can make you save a lot of troubles when something happens I used "quick connectors" before and after pump, thank and filters. It costs some more bahts but you will be thankful you have them the day you will have to remove pump, filter or change thank.

Oh yes! Don't choose a too big pump. The old pipes might not support the high pressure...

Very useful advice! My word if I wouldn't have had a 2 h power outage

Quick connector with O-rings. Can connect two PVC pipes without gluing:

(35 Baht or so for 1/2")

[steve73]

A little more complex - but this get's around the problem of not wanting to pump direct from the mains...

Use a very small tank fed direct from the mains via a float valve, and a small pump to pump from here to your normal larger tank... this pump to start with a low level in your main tank, but protected from running dry with a low level switch on your main tank... (Put a filter in before your main tank if you need it - i.e. if the mains water is bad - and you'll have enough pressure to backwash it better then using the mains directly.) Then run your main house supply pump from the main tank.. you can use a combined pressure/flow switch or protect it from running dry with a separate low float on the main tank.

I use a cheap 200 lt plastic drum for my break tank, and a very small pump to transfer to the main tank.. doesn't add much cost to the overall system and improves reliability.

Keep the water level as high as possible in your main tank to give maximum volume if the mains supply is off for more than a day or two... As to trying to raise the main tank to eliminate the main house pump, as others have said - there's little point unless you raise it more than 15m or so... if you suffer with too many power outs, then buy a small generator just to run the pump (and perhaps lights), or fit a DC water pump powered by a car battery... a lott less hassle than building a large tower.

[williewolf]

Yeah, I think that was my original diagram from wayyy back, evidently I should have charged royalties

no this was yours crossy, NOTE THE NON-RETURN VALVE!! This is the set up I used . Thank you very much

[joshstiles]

if hes going to start putting inline pumps in he might as well go the whole hog and have a bore hole drilled, and an auto pump,

we have this for the house and like many i dont have a tank at all, just the bore hole with the pump on top conected to the house, been like that for years no problems,

after all thats what auto pumps are for, i can never understand why some have big water towers as well as auto pumps,? i could be wrong but like i say our as been like this for years and no trouble,

its about 5k to drill the bore hole and another 5, or 6 for the pump

Where can you drill a borehole for B 5000? Are you talking about a borehole or a well ? Depending on the dept a borehole could be B 200 000 plus.

But I agree keep it simple. According to me two ways for the communual water. The first is an above ground tank, with the potential problem that at certain times the pressure of the comunual water may be to low to fill it. The second option (which most Thai's in our area use) is to have a below ground tank. The below ground tank doesn't need the same pressure to refill as the above ground tank and is easy to build, but you need a pump to have water pressure in the house. The borehole or well is an option but I would first talk to people in the area to find out how deep the water are and the quality of the water. Our borehole and equipment costed B 170 000 and my estimation on a well would be B 15 000 (depending on your pump, the dept of the well and excluding storage).

Good luck.

i live in a village just outside wangnamyen,

and to drill a bore hole 18mtrs deep 2 inch diamiter was just over 5k,

cab i ask how many bore holes you have?

ive got 3 2 for the house and one for the pigs,

and an auto pump is 5 to 6 k,

its a 2 inch bore with a 1 inch suction pipe to the pump,

ok, this is what ive got and been good for years,, this is the thing with thai visa nowadays you post what youve got or done from experience and get shot down,

have fun with yur tanks, dont forget a qube of water is a ton

just an additional note: The people who pay 150,000 - 200,000 baht for a bore are to "uneducated" to know that they have been scammed

many foreigners of course pay this and have no idea they were scammed or have so much money that they don't care.

I had 2 bores and pumps in Yasothon and paid only 10,000b for each. If you know what you want and know the cost locally you won't be paying what the other idiots "uneducated" have paid.

Shop around for the going rate....I doubt you will pay more the 20k.

[Mudcrab]

if hes going to start putting inline pumps in he might as well go the whole hog and have a bore hole drilled, and an auto pump,

we have this for the house and like many i dont have a tank at all, just the bore hole with the pump on top conected to the house, been like that for years no problems,

after all thats what auto pumps are for, i can never understand why some have big water towers as well as auto pumps,? i could be wrong but like i say our as been like this for years and no trouble,

its about 5k to drill the bore hole and another 5, or 6 for the pump

Where can you drill a borehole for B 5000? Are you talking about a borehole or a well ? Depending on the dept a borehole could be B 200 000 plus.

But I agree keep it simple. According to me two ways for the communual water. The first is an above ground tank, with the potential problem that at certain times the pressure of the comunual water may be to low to fill it. The second option (which most Thai's in our area use) is to have a below ground tank. The below ground tank doesn't need the same pressure to refill as the above ground tank and is easy to build, but you need a pump to have water pressure in the house. The borehole or well is an option but I would first talk to people in the area to find out how deep the water are and the quality of the water. Our borehole and equipment costed B 170 000 and my estimation on a well would be B 15 000 (depending on your pump, the dept of the well and excluding storage).

Good luck.

Had a bore drilled about 2 years ago. 27 metres - 3000 baht in Surin district. Neat little drill setup - unload off the ute and setup by 2 blokes.

The bore casing is about 100mm or 4 inch PVC. It fouled up originally but they came back and drilled a little deeper and fixed it up.

Put in a small jet pump for 5000 baht I think it was. Got rid of the pressure switch and installed a better pressure/flow pump controller.

Works great. Good pressure for the shower etc. Hasn't run dry yet.

[Mudcrab]

With the bottom of the tank at about 2.5m above your outlet, this will give you 3.5psi of pressure at your outlet. As your tank fills, that pressure will increase and if your tank is 2.5m high and full, that will give you another 3.5psi making it 7psi at your outlet. This might be enough to run a shower heater but I'm not sure but remember, as your water level drops, your pressure at the outlet decreases. The size of your water pipes should be considered as well, as the smaller the pipes, the less the deliverable volume.

A simple calculation to work out the pressure is H (water height in feet) x 8.3 (weight of water in pounds per gallon) x 0.052 and this will give your water pressure in psi. If your using meters for your height, just multiply your answer by 3.281. The minimum required pressure to run your electric shower should be on the box so check that out first before you decide how high to put your tank. In the end you may just have to fit a pump from your tank. Good luck with it anyway.

Or even simpler - 2 feet of water will give around 1psi of pressure.

This a really rough guide as 27 inches of water will give 1psi but for a simple estimate take the height of your water level in feet and divide by two for pressure in pounds per square inch.

10 foot high is 5 psi, 20 foot high is 10 psi etc etc.

[MrY]

Did my setup similar to the diagram. The fancier [Japanese] pumps were 5-7000 baht so I bought a cheap Chinese one (1500b) and made a pressure accumulator from 6m of 6 inch pipe (!) for it as they tend to 'cycle' a lot with their tiny accumulator. Reliability? 5 years and counting...

[khunPer]

If it can be any help for OP, I have a water tank in my house and use the pressure from the tank only.

I have a fairly small 900 liters tank on the attic, supplied from a well.

On the top-floor the bottom of the water tank is about 3 meter over floor level, i.e. some 4½ meter to the top water level. In average some to meters (2 atm.) water pressure for showerhead and water heater. That is not much, but it works, however not that much water pressure, just enough for the water heater to work and an acceptable shower pressure.

I would think you should need two water tanks, one at ground level for storage, filling up with community/town water (when available), and a small pump to fill up a raised tank. OP talks about 10,000 or 15,000 liters, that is 10 to 15 cubic meters and sounds like an awful lot – the structure shall be able to carry a weight of at least some 16 tons of water plus tank – around 1,500 liters sounds more reasonable. However placing some large storage water tanks direct on the ground, may not cause any structure problem.

You can use a small automatic pressure pump to fill the top-level tank from the ground storage tanks. A simple floating valve at the top tank will do the job and start the pressure pump (I use that for the well pump). However, it may make more sense just to leave water tanks on the ground and use a small pressure water pump for water to the in-house installation, which will also give you a nice water pressure at all times. You can buy a floater-switch (don’t know if I use correct English word), so mains power is only switched on to the pump, when the water level is high enough for the pump to work (running dry will damage the pump). I think the floater switch is fairly affordable, and a small good quality pressure pump can be obtained from around 5,000 baht.

Consider a filter on the town water inlet, so you get clean water into your tank(s) – a small simple ceramic filter will do the job and costs around 1,000 baht, and is easy to clean. You can consider two filters, one at the town water inlet, and another after your pressure pump to make sure you don’t get debris from the tank(s) into your pipes.

To keep the water fresh in the tank you can consider using a simple small aquarium pump to mix air (oxygen) into the water, which is the method used at water plants to clean water and remove bad smell, known as “water steps”. Oxygen will also kill some bacteria in the water.

If you use ground level storage water tank(s), you just let the town water into the storage tank instead of a T-junction, and supply from that via your own pump. However also using a T-junction (controlled with valves) you can use the direct supply from town water in case of pump-problems.

Wish you good luck with your project...

[outlaw11wa]

I hand the same issue in periods of higher usage there was minimal water pressure in home and in town. I overcame this by having a bore put down. On the surface I have a Hitachi constant pressure electric pump. This joins into the property supply with a tee piece on the house side of the water meter. Close the stop cock on the meter and you are not feeding the entire neighbourhood as well as yourself. Yes beautiful pressure and never experienced lack of water pressure again since Dec 2012. Working fine I do need to complete the system though. The water quality is okay but must be a high percentage of limestone and salts coming from the bore because I did replace a few calcified taps last month when I was there. Another addition might be a suitable filter to remove the calcium problem. A sediment tank might be the answer but that might require a second pump so I still have some research to do on that matter. Yes we do now and previously use the large water bottles for cooking and consumption. But that is the norm even when mains pressure is available. Oh those Hitachi Pumps are cheap. Putting the bore down is cheap also. And PVC pricing in Thailand is a dream.

Hope it works for you.