Setting on ground water tank instead of using water pump - will it work?

[srgbog]

Hi,

I moving to a new house and the new house have underground water tank and a water pump used to deliver the water from the underground water tank to the house... Each time I use water I use electricity...

At my previous house there was on ground water tank (2000L. I think) - and it was delivering water with good water pressure to 2 storey house without any water pump. Seems that this system

was using the water weight inside the water tank to deliver the water to the house... 

Please advice if I will replace the underground water tank with on ground water tank - will this system deliver the water to the house without using a water pump?

And if yes, do I need some specific tank size to get enough of water weight inside the tank to deliver the water to the house?

Edited July 2, 2019 by srgbog

[bankruatsteve]

Hmm.  Not likely that a ground level tank is delivering water without a pump.  It was probably being bypassed.  IE: the mains with good pressure were feeding your house supply - not the tank.  Check if your current system is set up for that to avoid pump use.  If there is not bypass valve, you could add one.  Otherwise, you will need the pump.

[sometimewoodworker]

4 hours ago, srgbog said:

Please advice if I will replace the underground water tank with on ground water tank - will this system deliver the water to the house without using a water pump?

No it will not.

 

You need a tank at least 10 metres above the top outlet for moderate pressure (1 ATM 14.6 psi), the size doesn't matter.

 

Our immediate use tank is about 3 metres above the taps and supplies low pressure shower water when the power is off.

 

 

Edited July 3, 2019 by sometimewoodworker

[simon43]

Seems that this system

was using the water weight inside the water tank to deliver the water to the house... 

 

Think for a moment about what you just said ????  If this were true, why bother with putting your water tank up on a tower.....

[Artisi]

If water ran up hill like you are saying, "the ground tank was delivering water to 2nd story" why would there be a need for any pump in any situation. 

Water DOESN'T run up hill. 

[userabcd]

The water tank needs to be above the highest outlet point for the water to flow out due to gravity.

 

For every 15m of static head height above your outlet equates to roughly 1 bar pressure.

 

If the tank is on the ground and is below your water outlets you will certainly need a pump.

[brianthainess]

Doh !

[eyecatcher]

So to answer your question, if the underground tank is doing its job correctly, leave the damn thing alone and worry about something else.

[Naam]

6 hours ago, srgbog said:

At my previous house there was on ground water tank (2000L. I think) - and it was delivering water with good water pressure to 2 storey house without any water pump. Seems that this system

was using the water weight inside the water tank to deliver the water to the house... 

just when you think you heard all thaivisa fairy tales...

[srgbog]

Thank you very much for your replies

I got the idea...

[eyecatcher]

1 hour ago, srgbog said:

Thank you very much for your replies

I got the idea...

....and off he goes with his tail between his legs

[sometimewoodworker]

4 hours ago, userabcd said:

The water tank needs to be above the highest outlet point for the water to flow out due to gravity.

 

For every 15m of static head height above your outlet equates to roughly 1 bar pressure.

 

If the tank is on the ground and is below your water outlets you will certainly need a pump.

You have your physics wrong 1 bar = 1 ATM = 14.6 psi = 10 meters of head above your outlet. 

 

So 15m = 1.5 bar = about 22 psi

Edited July 3, 2019 by sometimewoodworker

[userabcd]

45 minutes ago, sometimewoodworker said:

You have your physics wrong 1 bar = 1 ATM = 14.6 psi = 10 meters of head above your outlet. 

 

So 15m = 1.5 bar = about 22 psi

Yes you are right, for every 10m approx. Thanks for the correction.

[Fruit Trader]

1 hour ago, eyecatcher said:

....and off he goes with his tail between his legs

He goes off thinking why can't people just explain without making disparaging smart ass comments.

[srgbog]

5 hours ago, Naam said:

just when you think you heard all thaivisa fairy tales...

Show must go on ????

[CharlieH]

bickering removed.

[JAG]

I have a tank on a tower some 2m above the level of the taps and shower. An automatic pump pressurises the water, to feed both bathrooms (one "western" and one "Thai") and the kitchen. The tank is filled from the mains or by water pumped from a well - the village water supply can be erratic sometimes. This works well enough, and seems to use very little electricity.

 

Being an inventive sort of chap I have devised a splendid arrangement of pipes and valves, attached to the back wall of the house, which allows me to select "mains" or "tank/pump" for the kitchen, "Thai style" shower (tiled tank), toilet in the "Thai hong nam" and the water supply to the "western" bathroom (shower and toilet). The resulting arrangement of blue pipes and valves would outfox Red Adair!. I rather enjoy controlling it, but it really annoys the wife so for domestic harmony I leave things set for the kitchen and "Thai" shower to be supplied from the mains, and the rest from the tank/pump. I did produce a laminated card, laboriously translated into Thai, explaining which valve did which, but it only resulted in a caustic comment along the lines of "think too much".

 

I hope this information has added some spice to what may otherwise have been a mundane Wednesday evening...

Edited July 3, 2019 by JAG

[sometimewoodworker]

11 hours ago, JAG said:

I have a tank on a tower some 2m above the level of the taps and shower. An automatic pump pressurises the water, to feed both bathrooms (one "western" and one "Thai") and the kitchen. The tank is filled from the mains or by water pumped from a well - the village water supply can be erratic sometimes. This works well enough, and seems to use very little electricity.

 

Being an inventive sort of chap I have devised a splendid arrangement of pipes and valves, attached to the back wall of the house, which allows me to select "mains" or "tank/pump" for the kitchen, "Thai style" shower (tiled tank), toilet in the "Thai hong nam" and the water supply to the "western" bathroom (shower and toilet). The resulting arrangement of blue pipes and valves would outfox Red Adair!. I rather enjoy controlling it, but it really annoys the wife so for domestic harmony I leave things set for the kitchen and "Thai" shower to be supplied from the mains, and the rest from the tank/pump. I did produce a laminated card, laboriously translated into Thai, explaining which valve did which, but it only resulted in a caustic comment along the lines of "think too much".

 

I hope this information has added some spice to what may otherwise have been a mundane Wednesday evening...

Having a little bit of a similar setup, though with low level storage as well, I devised a way of feeding the house without using valves and still using the tank directly always so the, sometimes dirty, village water always has time to settle.

[SimpleMan555]

20 hours ago, sometimewoodworker said:

You have your physics wrong 1 bar = 1 ATM = 14.6 psi = 10 meters of head above your outlet. 

 

So 15m = 1.5 bar = about 22 psi

FYI: While the terms Bar and ATM are often interchanged, they are not equal with 1 atm = 1.01325 bar. 

The use of 10 meters to establish 1 ATM (Bar) is generally correct for seawater, while freshwater with its lower density, 1 ATM(Bar) is generally achieved at 10.1 meters of head or depth below the water level.

In most applications, the term 'Bar' is slowly being deprecated of the internationally established constant the Atmosphere or ATM (14.696 psi, often rounded to 14.7). 
 

In regards to residential water systems the small differences in the numbers as insignificant, and the use of 1 ATM (14.7 psi) or 1 Bar both achieved at roughly 10m, should not offend the Gods of Physics ????
      

[Huckenfell]

On 7/3/2019 at 2:29 PM, Fruit Trader said:

He goes off thinking why can't people just explain without making disparaging smart ass comments.

Some just cannot help themselves and like old fishwives pick at everything and everybody.  Grrrrr !

[albertik]

To the OP.... long story short----------You will need a pump to supply your house if village supply is absent.

I have an above ground tank (4 meters) but still only enough pressure to supply downstairs kitchen, toilets and shower. Upstairs shower, although lower in elevation than the elevated tank, has useless minimal pressure.  Can refill toilet tank over time, but useless for shower. This example is what happens when electricity is down and I must rely on gravity.

[JAS21]

On 7/4/2019 at 7:17 AM, sometimewoodworker said:

Having a little bit of a similar setup, though with low level storage as well, I devised a way of feeding the house without using valves and still using the tank directly always so the, sometimes dirty, village water always has time to settle.

Did you glue the lid shut...

[Daffy D]

My water tank is 6mt off the ground and I still had to fit a pump to get decent pressure in the ground floor shower. 

 

Could have saved a bundle of money not built a tower and had the tank sitting on the ground 

 

 

 

 

[sometimewoodworker]

1 hour ago, JAS21 said:

 

On 7/4/2019 at 7:17 AM, sometimewoodworker said:

Having a little bit of a similar setup, though with low level storage as well, I devised a way of feeding the house without using valves and still using the tank directly always so the, sometimes dirty, village water always has time to settle.

Did you glue the lid shut...

 

There are 4 tanks at the moment, none of them have lids that are glued shut, I don't know why you would want to do that, one has a screw on lid the others can be bolted shut but I haven't bothered as in the location they are in there is no danger of them coming off.

 

 

[ThePioneer]

1 hour ago, Daffy D said:

My water tank is 6mt off the ground and I still had to fit a pump to get decent pressure in the ground floor shower. 

 

Could have saved a bundle of money not built a tower and had the tank sitting on the ground 

 

 

 

 

The tower is your water supply UPS

[JAS21]

21 minutes ago, sometimewoodworker said:

There are 4 tanks at the moment, none of them have lids that are glued shut, I don't know why you would want to do that, one has a screw on lid the others can be bolted shut but I haven't bothered as in the location they are in there is no danger of them coming off.

 

 

 It just seems to me if you are getting water into your house without a pump you will be using mains pressure as it sounds that your tanks are at ground level. 

 

 Now if you are putting water through the tank as it appears unless they are sealed you would normally lose all your pressure.

 

 That was my thinking  ....but you have done it by ......./

[sometimewoodworker]

3 hours ago, JAS21 said:

 It just seems to me if you are getting water into your house without a pump you will be using mains pressure as it sounds that your tanks are at ground level. 

 

 Now if you are putting water through the tank as it appears unless they are sealed you would normally lose all your pressure.

 

 That was my thinking  ....but you have done it by ......./

I understand now.

 

The mains feeds that goes into the 750kl storage tanks at ground level is controlled by a normal ball valve. Once that shuts off there is usually enough village water pressure to feed the ready use tank that is about 5~6 metres above that level that is also controlled by a ball valve.

 

However if the water level in the ready use tank falls to about ½ full that triggers the float switch in that tank, that turns on the inexpensive pump at ground level which because of non return valves pumps water from the 750kl reserves up to the ready use tank. The float switch is set to turn off at about 9/10 of full a little lower than the ball valve, so that remains open until the village water pressure takes over again.

 

So there are no pressurised tanks, no valves to change, nothing to do until the bottom tanks run dry and that will be at least 6 weeks of normal usage, a lot more if we stop using the washing machines.

 

In fact my wife told me last week that the villagers were upset because the water supply had been cutoff for at least 6 days due to a burst pipe. We didn't notice anything, we may hear the top tank filling if the bottom pump is working as the fill is much faster.

 

Here is one of the low level tanks, so impossible to pressurise.

Edited September 8, 2019 by sometimewoodworker