House Water tank Pipe

[nigelforbes]

I’m going to install a new water tank at the MiL’s house and I have some questions regarding pipe size and configuration.

 

MiL’s house in the rural village is connected to the city water supply, the pipe from the water meter to the house is only half inch (13mm). As far as I can tell the feed pipe into the meter (road side) is also the same size.

 

The water inlet pipe is going to feed a 1,000 litre water tank, this in turn will feed up to six outlets, three at ground level, three at first floor level. It’s unlikely that more than two outlets will operate at the same time, for 98% of the time.

 

Phase I of the installation will be to use the tank and city supply in unison, using a check valve and float valve, Phase II, some weeks later,  will see a pump installed to increase pressure to the first floor.

 

My questions are: 13 mm into the house is quite small, will this lead to some flow issues, until the pump is installed and will a pump even handle such a small feed pipe?

 

Also, what’s the best way to divide the flow between the six outlets, in series, one after the other or divide the flow by floor?

 

Any tips, gratefully received.

[gamb00ler]

It seems there is currently no pump at your MiL's house.  Is that correct?

 

Isn't the standard to start the floor numbers at 1 (ground)?  So in a 2 storey house the higher floor is the 2nd floor, n'est pas?

 

You can't really use a tank without a pump.  Create a system as shown in the diagram below.

 

Here's a diagram courtesy of @Crossy.  I copied this diagram from one of his posts.

 

Edited April 28, 2023 by gamb00ler

[nigelforbes]

That's correct, there is no pump at present. But currently, city water supply pressure is sufficient to feed the upstairs outlets, I intend to continue to use that in the short term albeit I'm adding the tank into the loop.

[gamb00ler]

5 minutes ago, nigelforbes said:

That's correct, there is no pump at present. But currently, city water supply pressure is sufficient to feed the upstairs outlets, I intend to continue to use that in the short term albeit I'm adding the tank into the loop.

I don't think you can just add a tank only.  How will the pressure from the city water be maintained through the tank?  The tank is generally not sealed so there will be no pressure to raise water to the upstairs outlets.

 

You could potentially install your tank on a tower, but you didn't mention that feature.

Edited April 28, 2023 by gamb00ler

[transam]

If the town water is filling the tank, you will not have any pressure elsewhere while it is doing it.

The 13mm feed is OK if it is filling a tank, that feeds a pump, which will feed all the house, it is what I have....????

[nigelforbes]

1 minute ago, gamb00ler said:

I don't think you can just add a tank only.  How will the pressure from the city water be maintained through the tank?  The tank is generally not sealed so there will be no pressure to raise water to the upstairs outlets.

The schematic below is broadly the one I've adopted, minus the pump in the short term. The tank will provide gravity feed to the downstairs outlets but will will not be used when upstairs flow is required because the water height in the tank is below that of the outlets upstairs. As a consequence, the float valve in the tank remains closed and supply to the upstairs is solely from the City supply, via the check valve and pump bi-pass....the upstairs supply water circuit in that scenario is almost exactly what it is now, without the tank.

 

[nigelforbes]

1 minute ago, transam said:

If the town water is filling the tank, you will not have any pressure elsewhere while it is doing it.

The 13mm feed is OK if it is filling a tank, that feeds a pump, which will feed all the house, it is what I have....????

Yes, this was my concern and why I was trying to understand how to pipe the outlets, in series or separated by floor. I think that if the tank is in the process of being filled by the City supply, water supply to the downstairs outlets will still be OK. But the incoming City supply in that scenario will be split between flow to the tank and flow to the upstairs outlets which as you say, will result in little or no pressure upstairs. Is there any way around that without first adding a pump? As I said, there is unlikely to be more than one outlet used at a time so this may not be a show stopper, for a limited time.

[Bill97]

54 minutes ago, nigelforbes said:

My questions are: 13 mm into the house is quite small, will this lead to some flow issues, until the pump is installed and will a pump even handle such a small feed pipe?

Feed pipe should be same size as pump output.  So choose the pump,  3/4” or 1” to get good flow.  Not 1/2”.

 

54 minutes ago, nigelforbes said:

what’s the best way to divide the flow between the six outlets

Most homes have one pipe going in from the pump then branch depending on layout of usage points .

 

I like one inch distribution then reduce to 1/2” at outlet connections.

54 minutes ago, nigelforbes said:

Phase I of the installation will be to use the tank and city supply in unison, using a check valve and float valve

Is the tank elevated?  If not I don’t you can use it without a pump.  

 

[nigelforbes]

1 minute ago, Bill97 said:

Feed pipe should be same size as pump output.  So choose the pump,  3/4” or 1” to get good flow.  Not 1/2”.

 

Most homes have one pipe going in from the pump then branch depending on layout of usage points .

 

I like one inch distribution then reduce to 1/2” at outlet connections.

Is the tank elevated?  If not I don’t you can use it without a pump.  

 

"Feed pipe should be same size as pump output.  So choose the pump,  3/4” or 1” to get good flow.  Not 1/2”.

 

I have no control over the feed pipe size, it's half inch from the street, into the meter and the same from the meter into the house.

 

I can't use 1 inch distribution when the feed pipe is only half an inch.

 

The water level in the tank is significantly higher than the height of the downstairs outlets hence downstairs gravity feed via the tank is not likely to be an issue. As said, upstairs outlets cannot use the tank supply because of the height difference, BUT, it can continue to use the City supply feed that bi-passes the tank. The only issue with that scenario is as Transam said, when the tank is being filled by the City supply, upstairs flow will be near to zero. But once again, there is unlikely to be more than one outlet point in use at any point in time for 98% of the time. Perhaps MiL will do a load of laundry and flush a toilet at the same time, in which case the cistern will take time to refill.

[transam]

If the house has a pump feed it doesn't matter what size gov water pipe feeding the tank, the tank outlet is what matters, it is feeding the pump, I have 1" pipe from the bottom of the tank feeding the pump and 1" from there on until it branches in different directions feeding the taps, showers etc....

Also plumbed in is a bi-pass, in case one has a pump/electricity problem.

 

At my place, the gov water pressure will not get upstairs.

I have a 250w non-pressure tank pump, good pressure upstairs......????

Edited April 28, 2023 by transam

[gamb00ler]

The benefit from just adding the tank will be minimal.  You say that Phase II will be only a short time later.

 

If it's not DIY, just do the entire system with one visit from the water system contractor.

[nigelforbes]

1 minute ago, transam said:

If the house has a pump fed it doesn't matter what size gov water pipe feeding the tank, the tank outlet is what matters, it is feeding the pump, I have 1" pipe from the bottom of the tank feeding the pump and 1" from there on until it branches in different directions feeding the taps, showers etc....

Also plumbed in is a bi-pass, in case one has a pump/electricity problem.

 

At my place, the gov water pressure will not get upstairs.

I have a 250w non-pressure tank pump, good pressure upstairs......????

Sure, from the tank to the pump is not an issue and if only the tank supply (minus the pump) was being used, one inch up to the branch is still OK. BUT that means the City supply (half inch) that bi-passes the tank has to mate into a one inch (or three quarter) feed that in turn leads to the branch mentioned previously. Half inch supply into a one inch pipe wont work well at all.

[nigelforbes]

Just now, gamb00ler said:

The benefit from just adding the tank will be minimal.  You say that Phase II will be only a short time later.

 

If it's not DIY, just do the entire system with one visit from the water system contractor.

The purpose of installing the tank is because City supply is sometimes shut off for days at a time, the tank gives MiL a water supply reserve for use at such time.

 

Yes, I would like to be able to instal the pump and the tank at the same time because this would simplify matters greatly. I won't bore everyone with the reasons why this is problematic, please just accept that it is unlikely to happen in the short term.

[Bill97]

7 minutes ago, nigelforbes said:

I can't use 1 inch distribution when the feed pipe is only half an inch.

From the tank thru the pump you can feed the house with 1”.

 

Why not do the pump and the tank at the same time?  Gravity feed from tank into house will be very very low pressure and volume.

[transam]

1 minute ago, nigelforbes said:

Sure, from the tank to the pump is not an issue and if only the tank supply (minus the pump) was being used, one inch up to the branch is still OK. BUT that means the City supply (half inch) that bi-passes the tank has to mate into a one inch (or three quarter) feed that in turn leads to the branch mentioned previously. Half inch supply into a one inch pipe wont work well at all.

The bypass is a get you out of trouble fix only, for pump failure or electric off..........????

It requires a series of on off stop cocks, a couple to isolate the pump, and a couple to open up gov water to the house...

[gamb00ler]

4 minutes ago, Bill97 said:

From the tank thru the pump you can feed the house with 1”.

 

Why not do the pump and the tank at the same time?  Gravity feed from tank into house will be very very low pressure and volume.

yeah... 2 m height gives only 2.85 lbs pressure

[nigelforbes]

I think what I’m leaning towards is to maintain the half inch pipe from the street to the tank, that can’t be changed anyway.

 

Three quarters inch from the tank to the base of the house and half inch pipe from the base of the house to the individual outlets. A pump can be inserted into the three quarter inch pipe later.

 

The bi-pass from the City supply to the pipe at the base of the house can stay as half inch and will join into the three quarter inch pipe. Downstairs flow and volume via the tank/City supply combo should continue to be OK, but upstairs flow is likely to be poor at times.

 

[nigelforbes]

9 minutes ago, transam said:

The bypass is a get you out of trouble fix only, for pump failure or electric off..........????

It requires a series of on off stop cocks, a couple to isolate the pump, and a couple to open up gov water to the house...

We have similar at our house. Water supply is via the City supply but the tank is there if there is no supply....it is seamless and requires no intervention although, as you say, components can be isolated if required.

 

The tank is unable to supply the upstairs outlets because of height and gravity etc., that means the City supply still operates and feeds those outlets, via the bi-pass, when the tank is full and the ball valve is closed.  Or am I missing something here?

[nigelforbes]

12 minutes ago, gamb00ler said:

yeah... 2 m height gives only 2.85 lbs pressure

True, assuming only the tank supply is used, without a pump and there is no City supply. But under normal operating circumstances, the City supply will be available and this is already capable of feeding the upstairs outlets with good pressure and flow.

[nigelforbes]

I think I'm as per the schematic I posted earlier, half inch to the tank, half inch along the mains bi-pass and three quarter inch from tank to house base (via a pump later) and half inch in to individual outlets.

 

Remember, the primary purpose is to provide a supply when the City supply stops. Remember also, that concurrent usage of outlets is absolutely minimal and that existing pressure from City supply is very good.

 

What problems does anyone see?

[transam]

Just now, nigelforbes said:

I think I'm as per the schematic I posted earlier, half inch to the tank, half inch along the mains bi-pass and three quarter inch from tank to house base (via a pump later) and half inch in to individual outlets.

 

Remember, the primary purpose is to provide a supply when the City supply stops. Remember also, that concurrent usage of outlets is absolutely minimal and that existing pressure from City supply is very good.

 

What problems does anyone see?

Depends on what you are used to, my showers upstairs are extremely invigorating, the toilet refills in seconds, we have back-to-back toilets, no ploblems with the pump water supply....????

[Bill97]

What is the current pipe size in the house?  All one size?

[nigelforbes]

3 minutes ago, transam said:

Depends on what you are used to, my showers upstairs are extremely invigorating, the toilet refills in seconds, we have back-to-back toilets, no ploblems with the pump water supply....????

Used to? This is MiL's house, it's a very poor basic village in the middle of nowhere, we had great difficulty getting her to stop using stone jars of water in the bathroom. 

[nigelforbes]

1 minute ago, Bill97 said:

What is the current pipe size in the house?  All one size?

All half inch everywhere but easily changed. 

[transam]

2 minutes ago, nigelforbes said:

Used to? This is MiL's house, it's a very poor basic village in the middle of nowhere, we had great difficulty getting her to stop using stone jars of water in the bathroom. 

That reminds me of Mrs.T's late mum, when visiting, she would not use the showers, fear of electricity and folk being fried..

We had to rig up a bin and scoop in the garden, it wasn't a pretty sight....

[sometimewoodworker]

There is quite a lot of misinformation.

 

I have virtually everything that is being required.

1) you can have a ½” pipe feeding a 1 ½” pipe and you will have lower friction losses.

2) you can feed a upstairs outlet with city water even if your storage tank is on the ground floor (I have them, my upstairs tank is also feed by city water)

3) you have no need for shutoff valves despite @transam statement that they are needed.

20 minutes ago, nigelforbes said:

I think what I’m leaning towards is to maintain the half inch pipe from the street to the tank, that can’t be changed anyway.

If you own the pipe you can change the pipe. The shorter the length of ½” pipe you have the better the flow volume will be. The longer the ½” pipe the greater the friction the smaller the flow.

 

our house water supply is 

village to meter ½” about 4 meters.

meter to first storage tanks (7,500 litres) through a one way valve 32mm pipe

storage tanks have a ball valve shutoff

village water continues up to a high level 1,000 litre tank there is a ball valve shutoff the village water pressure usually fills the 1,000 litre tank

if the village water is cutoff there is a pump beside the 7,500 tanks that fills the high level tank this pump is controlled by a maximum minimum float switch 

the house water is all feed by a SCALA 2 pump from the 1,000 litre tank. 
all pipes are 32mm until the outlets.

 

the results of this is that the village water has been cut off occasionally for up to 2 weeks, we didn’t know until the neighbours started asking how we were managing.

as long as there is power we need to do nothing.

pumps fill tanks

village water fills tanks 

we just turn on the tap

[sometimewoodworker]

20 minutes ago, nigelforbes said:

What problems does anyone see?

Don’t use ½” pipe anywhere you don’t have to.

[transam]

2 minutes ago, sometimewoodworker said:

There is quite a lot of misinformation.

 

I have virtually everything that is being required.

1) you can have a ½” pipe feeding a 1 ½” pipe and you will have lower friction losses.

2) you can feed a upstairs outlet with city water even if your storage tank is on the ground floor (I have them, my upstairs tank is also feed by city water)

3) you have no need for shutoff valves despite @transam statement that they are needed.

If you own the pipe you can change the pipe. The shorter the length of ½” pipe you have the better the flow volume will be. The longer the ½” pipe the greater the friction the smaller the flow.

 

our house water supply is 

village to meter ½” about 4 meters.

meter to first storage tanks (7,500 litres) through a one way valve 32mm pipe

storage tanks have a ball valve shutoff

village water continues up to a high level 1,000 litre tank there is a ball valve shutoff the village water pressure usually fills the 1,000 litre tank

if the village water is cutoff there is a pump beside the 7,500 tanks that fills the high level tank this pump is controlled by a maximum minimum float switch 

the house water is all feed by a SCALA 2 pump from the 1,000 litre tank. 
all pipes are 32mm until the outlets.

 

the results of this is that the village water has been cut off occasionally for up to 2 weeks, we didn’t know until the neighbours started asking how we were managing.

as long as there is power we need to do nothing.

pumps fill tanks

village water fills tanks 

we just turn on the tap

3) I use shut off valves either side of the pump in case it has to be removed/replaced, which it has.

It saves one hell of a mess, and then water feed valves going around the missing pump can be opened up......

Up to you if you want to wear wellingtons, doing an easy job...

[billd766]

1 hour ago, transam said:

If the town water is filling the tank, you will not have any pressure elsewhere while it is doing it.

The 13mm feed is OK if it is filling a tank, that feeds a pump, which will feed all the house, it is what I have....????

And me. It has been installed for over 18 years and only 1 serious leak in that time.

 

I use a Mitsubishi EP-305R 300 watt water pump. It has 1 inch entry and exit ports with a shut off valve each side,  so that if I need to replace the pump it is easy. You can but the 1 to 1/2 adaptors at any hardware shop. That gives me plenty of pressure to the toilet sink and shower on the 2nd floor.

 

I have put in 2 x 5 micron cartridge filters before the pump to get rid of most of the sludge which doesn't sink to the bottom of the tank. The filters are bolted to my workshop wall and the pump is on a metal table to save me bending down. (I am 78).

 

I have 20 x 1,700 litre ongs for water storage as sometimes the water stops for a few days and then my wife goes to the tessaban and orders more with delivery by the fire truck.

Edited April 28, 2023 by billd766
added extra text

[nigelforbes]

2 minutes ago, sometimewoodworker said:

Don’t use ½” pipe anywhere you don’t have to.

Thank you for those things.

 

I don't know the distance from the city mains supply in the road to our meter, my guess is similar to your, around 4 meters. The distance from the meter to the tank location is around 20 meters (I guess). If the latter were replaced with say three quarter inch pipe, would the flow not be limited by the size of the pipe from the mains to the meter, which is half an inch? 

 

Secondly, you say not to use half inch pipe anywhere that is unnecessary, does that include the final run through the walls of the house, to the outlet at the point of use?