Very strange problem with tap water

[Na Fan]

We live in a community (moo baan) with its own water well. The village has its own ground pumps and central water tower and each house has a local tank with a local pump that distributes pressured water.

 

And that works fine, during the day.

 

But for about a month now, the water pressure starts going down every day to an absolute zero, starting at around 9pm, with there being no water at all at around midnight.

In the morning it's all back to normal again, until the same thing repeats itself again in the following evening.

 

And, that only happens to us, to our house. Nobody else.

 

I'm confused as hell. But does any of this sound familiar to anyone? Or do you have any idea what could possibly cause this?

 

Again, there is never a problem in the day. Always a problem at night. Every day.

 

[rumak]

you have your own tank and pump ,   so isn't THAT where the problem lies ?

 

if your tank is not being filled after a certain hour than the water in the moo bahn must get shut off at a certain time .        if that is the case,  you need a bigger tank.   

 

but while you do have water in your tank,  water pressure in your house should be same all the time.

does sound like you are confused as hell (as you say)

[Crossy]

Moved to DIY and a bunch of off-topic posts removed.

 

To our OP.

 

How big is your local tank?

Can you check how much water is in your tank before the pressure drops off?

Is your tank filling properly when the supply is on? (is there an incoming filter? Is it clogged?)

 

I suspect that @rumak is correct and you are running out of water.

[rumak]

i am a bit more awake now  ????       Yes,  as Crossy suggests,  check your tank  ( at different times during day).     When you use water in house , go out and check if water is coming into the tank from the source (moo bahn).    Should fill ,  same as a toilet does (if you have the common type tank that lets water in and has a "ball" type shut off when water reaches top level)

 

if that is working correctly,  then check at night when you say pressure goes down .  Is water in tank full ?   If not,  why is it not filling.        Since your pump works ok in daytime,  that would not seem to be the problem.      Many municipalities often shut water off at certain times to conserve water

[Crossy]

36 minutes ago, rumak said:

Since your pump works ok in daytime,  that would not seem to be the problem. 

 

It's possible that his pump has failed and the system is running on bypass and using village water pressure during the day, hence the pressure fall off at night.

 

@Na Fan is the pump actually running during the day? At night?

[rumak]

Just now, Crossy said:

 

It's possible that his pump has failed and the system is running on bypass and using village water pressure during the day, hence the pressure fall off at night.

 

@Na Fan is the pump actually running during the day? At night?

good system if he has bypass.    mine, if the pump isn't working there just isn't any water to the house (bathroom).     i  do not use tank/ pump  for kitchen or outside faucets so always have water even if electric is off .    

[Na Fan]

I don't have access to the tank - it's underground somewhere.

 

But I just realized that we can't hear our pump going if we e.g. turn on the tap in the bathroom.

 

Duh!

 

So yeah, it appears that you're right, and during the day, for some reason  the water is bypassing it somehow and gets into the house directly, and at night the village is cutting the water apparently (no idea why) and then, without the pump, we're dry.

 

[sometimewoodworker]

3 hours ago, Na Fan said:

and at night the village is cutting the water apparently (no idea why)

At the end of our village one user had bypassed the meter and was running the water all night to fill/keep full his rather large pond, that was why they cut the supply to a few hours morning and evening.

[mrwebb8825]

Solar pump? ????

[Lacessit]

If the OP can't hear his own pump going, he is only getting the village pressure.

Many pumps are designed with a rubber bladder filled with air. If that leaks so the bladder fills with water instead, nothing happens because the pressure sensor thinks it is seeing full pressure. Air is compressible, water is not.

[sometimewoodworker]

6 minutes ago, Lacessit said:

If the OP can't hear his own pump going, he is only getting the village pressure.

Many pumps are designed with a rubber bladder filled with air. If that leaks so the bladder fills with water instead, nothing happens because the pressure sensor thinks it is seeing full pressure. Air is compressible, water is not.

While a puncture in an air bladder will allow water in to the air pocket and will cause the pump to short cycle, it will not stop the pump working. As you are aware once a tap is opened the pressure is immediately reduced so your theory fails on that point.

 

It is far more likely that the pump has failed.

The air pocket is designed to even out the cycling due to the pressure difference. 

[jossthaifarang]

On 11/1/2020 at 7:59 AM, Crossy said:

 

It's possible that his pump has failed and the system is running on bypass and using village water pressure during the day, hence the pressure fall off at night.

 

@Na Fan is the pump actually running during the day? At night?

Exactly, my tank pump only works if the "city pump" pressure is too low. As long as the city pump pressure is high enough my pump doesnt work.

 

OP, go out and turn off the mains coming into your house during the day, then open the water in your house. Your pump should start, if not? Your pump is the problem. (Your pump normally has a pressure activation switch and that is probably the culprit)

[Crossy]

17 hours ago, Na Fan said:

But I just realized that we can't hear our pump going if we e.g. turn on the tap in the bathroom.

 

Just to verify try turning off your incoming supply during the day. Does the pump start when you open a tap?

 

If not time to start diagnosing the pump.

[Crossy]

A post attempting to de-rail the thread has been removed along with the response.

 

I will note that our pump still runs even with a waterlogged pressure tank, it just cycles fairly rapidly.

 

[Lacessit]

1 minute ago, Crossy said:

A post attempting to de-rail the thread has been removed.

 

I will note that our pump still runs even with a waterlogged pressure tank, it just cycles fairly rapisly.

 

If there is still some air in the bladder, it will happen as you describe.

[sometimewoodworker]

43 minutes ago, Lacessit said:

If there is still some air in the bladder, it will happen as you describe.

There doesn’t need to be any air in the bladder for the pump to run.
 

Of course with air in the tank you get sensible cycling and more even flow, but with no air the tank the pump will still work.

[hotchilli]

On 11/1/2020 at 1:16 AM, Na Fan said:

Again, there is never a problem in the day. Always a problem at night. Every day.

Check your water tank level, maybe daytime use is depleting it and it's not topping up.

[bankruatsteve]

Has manual bypass been ruled out?

[The Theory]

Check pump breaker 1st.