Water tank empty daily, no visible water leaking anywhere

[how241]

Hello,  looking for some help please.  I am living in a townhouse on the darkside. Very recently the water tank is empty almost daily.  I don't see any wetness anywhere or any signs of water leakage.  Any thoughts ?  Thanks for any suggestions. 

[richard_smith237]

First thing to check... Is the water pump running constantly ???    IF so.... its leaking somewhere (most likely under the house where you can't see it)... 

 

If not, perhaps the tank isn't getting replenished - then its a mains issue.

 

Has your water bill gone up ?

[worgeordie]

It could be draining back into supply side if you don"t have a one way valve on it
and also if water pressure is not high enough , if you dont see a leak anywhere ,

that could be the problem.

 

regards worgeordie

[how241]

There is no problem with the water supply, coming to the house,  refiling the tank.  If I turn of this water supply,  the tank will soon be empty.  As if it is leaking out but no water is anywhere to be seen.  It is dry everywhere around the water tank and the patio.  I am in Parkrungeng, off soi Khao Talo.  I pay my monthly water bill to a small private post office type shop.

[how241]

16 minutes ago, worgeordie said:

It could be draining back into supply side if you don"t have a one way valve on it
and also if water pressure is not high enough , if you dont see a leak anywhere ,

that could be the problem.

 

regards worgeordie

It's been fine for 6 years,  never had any problems.  The supply side adds water up high,  close to the top of the water tank so even if it was draining back it could only go down a little bit.  Now it goes down to almost empty. 

[CharlieKo]

Has someone tapped into your water supply, without you realising it? Do you have access to all the pipework to/from your condo. 

[chickenslegs]

When your tank is full, close the valve next to your water meter (so water can not flow back). If the water in your tank drains away, you have a leak somewhere on your property. It could even be underneath the house.

 

If the water in your tank does not drain away, the problem is a backflow into the mains supply. This can be caused by someone upstream of your property using a pump to draw water from the mains supply. The solution would be to install a non-return valve between your water meter and your tank, as suggested by @worgeordie above.

[how241]

18 minutes ago, CharlieKo said:

Has someone tapped into your water supply, without you realising it? Do you have access to all the pipework to/from your condo. 

It's a townhouse,  not a condo,  and yes I have access to all the pipeworks.

[how241]

7 minutes ago, chickenslegs said:

When your tank is full, close the valve next to your water meter (so water can not flow back). If the water in your tank drains away, you have a leak somewhere on your property. It could even be underneath the house.

 

If the water in your tank does not drain away, the problem is a backflow into the mains supply. This can be caused by someone upstream of your property using a pump to draw water from the mains supply. The solution would be to install a non-return valve between your water meter and your tank, as suggested by @worgeordie above.

I'm not sure I follow what your saying.  After the tank is full,  I have turned off the supply valve.  After awhile,  the tank will become empty.  Other than the supply pipe,  the only other pipe is at the bottom of the water tank  and goes directly to the water pump.  All the area and pipes are dry.  The plastic tank is sitting inside the patio area on a tile floor,  which is dry. So much water is gone,  and to where.  Without a trace or wet area.  Very strange.  My Thai lady is thinking 'ghosts'...

[chickenslegs]

3 minutes ago, how241 said:

I'm not sure I follow what your saying.  After the tank is full,  I have turned off the supply valve.  After awhile,  the tank will become empty.  Other than the supply pipe,  the only other pipe is at the bottom of the water tank  and goes directly to the water pump.  All the area and pipes are dry.  The plastic tank is sitting inside the patio area on a tile floor,  which is dry. So much water is gone,  and to where.  Without a trace or wet area.  Very strange.  My Thai lady is thinking 'ghosts'...

Then the leak must be on your property. If your pump is cycling, the leak must be after the pump (maybe under the floor of the house. If the pump is not cycling, the leak must be somewhere between the tank and the pump (under the tiled patio?).

[richard_smith237]

1 hour ago, richard_smith237 said:

First thing to check... Is the water pump running constantly ???    IF so.... its leaking somewhere (most likely under the house where you can't see it)... 

 

Again....  IF the area around your tank is dry... there is a leak elsewhere, on or under your property (foundations perhaps where the water pipe run underneath and then up into the property)..... 

 

When there is water (i.e. before the tank runs empty) - does the water pump run constantly ?

[NoDisplayName]

Post a photo of the water tank with piping to the pump and then into the house.

 

The water flows thru the supply line outside the tank up to the top where it enters thru a float-operated valve.  The water cannot flow back out to the street.

 

Turn off all taps in the house.  Does the water pump cycle?  If so, then leak under the house.  If not, and the water level in the tank drops, then you probably have a crack in the bottom of the tank and the water is draining into the ground.

[couchpotato]

1 hour ago, CharlieKo said:

Has someone tapped into your water supply, without you realising it? Do you have access to all the pipework to/from your condo. 

He is in a house, not Condo, so individual water meter and piping to Tank.

[NoDisplayName]

Do you have a shutoff valve on the line from the tank to the pump?

Shut off the outflow from the tank to confirm water level drop.

[Polar Bear]

Have you checked the toilets to see if one is constantly running? If the valve isn't cutting off properly, the overflow just goes into the pan, so it's easy to miss. (The same thing can happen if the flush valve isn't closing properly, but then the tank will be empty when you want to flush it, so you usually notice that.)

[andygrr]

What type of tank is it. Is it an underground tank brick lined or an above ground tank.

[brianthainess]

14 hours ago, chickenslegs said:

When your tank is full, close the valve next to your water meter (so water can not flow back). If the water in your tank drains away, you have a leak somewhere on your property. It could even be underneath the house.

 

If the water in your tank does not drain away, the problem is a backflow into the mains supply. This can be caused by someone upstream of your property using a pump to draw water from the mains supply. The solution would be to install a non-return valve between your water meter and your tank, as suggested by @worgeordie above.

agree one of these.

 

[how241]

13 hours ago, richard_smith237 said:

When there is water (i.e. before the tank runs empty) - does the water pump run constantly ?

No,  the water pump runs the same as always.  Not so often.

[how241]

Thanks to all poster for their help and suggestions.  I have a lot to check out.  I appreciate the help.

[fredwiggy]

I have a well that I use to fill the water tank at my house in the country. The above ground pump pumps the water from the well through the pipe into the top of the tank. Water can not go back uphill so the water stays in the tank when it's full. The water pump to the house only runs when I need water in the sinks or toilets, and off otherwise. After I fill the tank, the next day it's almost empty. I also see no leaks anywhere but thought one had to be somewhere between the pump and the house, but in that case, the pump would cycle and I would hear it unless it's very slow but constant, but a trickle in the faucets does make the pump cycle so???This would mean there's a leak under the house between the pump and the house, and our builder wasn't the best, so I'm thinking he missed a leak that's been there ever since, so that means digging under the house to find it.

Edited April 23 by fredwiggy

[rwill]

Has your water bill gone up abnormally?

 

 

[newbee2022]

16 hours ago, how241 said:

Hello,  looking for some help please.  I am living in a townhouse on the darkside. Very recently the water tank is empty almost daily.  I don't see any wetness anywhere or any signs of water leakage.  Any thoughts ?  Thanks for any suggestions. 

Maybe someone regulate the water tap (inlet)

[Jaxxper]

I’d suspect the non return valve that is supposed to be fitted to the water delivery piping. If it’s old it may pass water ( particularly pumped water) back into the water main. I’d ask for the water board to come and check it out. 

[wwest5829]

17 hours ago, worgeordie said:

It could be draining back into supply side if you don"t have a one way valve on it
and also if water pressure is not high enough , if you dont see a leak anywhere ,

that could be the problem.

 

regards worgeordie

That was my first thought. I think you may have nailed the problem since there is no leak.

[rwill]

Do you have a bypass valve?  For when the power goes out and the pump does not run.  I once opened my bypass valve when the power went out and forgot to close it when power came back on and it emptied my water tank.

[arick]

Maybe a big water drinking beast in the tank.  

[NoDisplayName]

1 hour ago, fredwiggy said:

This would mean there's a leak under the house between the pump and the house, and our builder wasn't the best, so I'm thinking he missed a leak that's been there ever since, so that means digging under the house to find it.

 

Digging under the house is the last thing you want to do.

Install a cutoff valve somewhere before the line goes under the house, or between the tank and the pump to isolate the leak first.

[fredwiggy]

12 minutes ago, NoDisplayName said:

 

Digging under the house is the last thing you want to do.

Install a cutoff valve somewhere before the line goes under the house, or between the tank and the pump to isolate the leak first.

From the tank to the house and pump there's a split line. If there was just the one to the pump, the pump would cycle and I would hear it, so I'm guessing the other line that also goes into the house is leaking. I'm not sure where that other line goes but perhaps the toilets. It goes straight down into the ground from the tank then I'm not sure where.  I don't really understand how the builder rigged it because I wasn't here when they did the plumbing, and now he's out of the area so I can't ask him.

[NoDisplayName]

17 minutes ago, fredwiggy said:

From the tank to the house and pump there's a split line. If there was just the one to the pump, the pump would cycle and I would hear it, so I'm guessing the other line that also goes into the house is leaking. I'm not sure where that other line goes but perhaps the toilets. It goes straight down into the ground from the tank then I'm not sure where.  I don't really understand how the builder rigged it because I wasn't here when they did the plumbing, and now he's out of the area so I can't ask him.

 

That's strange.

The line from the tank splits......one branch goes to the pump then to the house, the other goes into the ground to unknown?

 

With the pump on, does it cycle for all faucets and toilets?

If you turn the pump off, do you get any flow anywhere?

[fredwiggy]

4 minutes ago, NoDisplayName said:

 

That's strange.

The line from the tank splits......one branch goes to the pump then to the house, the other goes into the ground to unknown?

 

With the pump on, does it cycle for all faucets and toilets?

If you turn the pump off, do you get any flow anywhere?

The pump goes on when water is needed.  The pump does go on to fill the toilets and sink use. I'll turn it off later and see what happens.