water from loft tank is returned to main line

Hi,
my apartment is at level 3.
Previously I have had Non return valve (check valve?) installed which restricted water going out from loft tank.The area I live at has hard water conditions which damages Non return valve frequently.

So I thought to have U tube from main line (High loop )



Ironically, physics principles dont allowing this to work and water from loft tank is getting drained to main line (siphoned?).

The piping inside is like seen in images,The plumber has installed vent pipe also, but it didn't worked out.


is there solution to this problem? I seek help from members in this forum

points to note,
1)I want to skip vent pipe manual switching on/off, as when I am out & water is available in main line it would come out of vent pipe (what is air release & vaccum insert valve? will it do?) what is optimum location of vent pipe & height & size ?

2) the input & output of loft tank is given to single point to have water circulated in my apartment, so that i can use loft tank/main line water in kitchen/toilets (etc)

picture of the new installed ck valve. i see a climpse of it.

and I "THINK" you have a swing check installed as a spring ck.

swing ck can only be installed on a plumb/level horizonital line. it ck gate, works by gravity , it swings

spring ck, can be installed both vertical/horiz. it uses a spring

frodo said:

picture of the new installed ck valve. i see a climpse of it.

and I "THINK" you have a swing check installed as a spring ck.

swing ck can only be installed on a plumb/level horizonital line. it ck gate, works by gravity , it swings

spring ck, can be installed both vertical/horiz. it uses a spring

Click to expand...

yep, the plumber has made that mistake,but the issue in the problem is not caused by this. As even if this check not works loft will be filled by both direction(from top & from bottom) Right? The issue is when I am not at home,when I come back I see the tank is drained,I have verified that level below apartment gets this returned water.(The high loop didn't worked out )
Also,I don't to wish to involve any type of check valve because of the corrosion issue due to hard water.

How to make high loop outside work as i desired/thought.

the check valve needs to be rotated so that it is level

once the ck valve is level. it will keep the water from leaving the tank

IF IT is installed correctly with the arrow pointed in the direction of flow and level


not real sure what else you are trying to do, but the ck is the reason water is coming back

others may have different ideas

frodo said:

the check valve needs to be rotated so that it is level

once the ck valve is level. it will keep the water from leaving the tank

IF IT is installed correctly with the arrow pointed in the direction of flow and level


not real sure what else you are trying to do, but the ck is the reason water is coming back

others may have different ideas

Click to expand...

yes, the ck is performing what it intends to do , that is to return water from the tank so i can use it(it may be failing so that water is traveling to tank from lower hole to fill the tank, which is not the problem for me as long as I can see tank is able to fill). but when this returned water goes out of apartment , through the high loop (outside), i thought it would at max travel the height of water tank , and wouldn't cross the loop successfully , keeping the tank water available only in apartment.

the water from down stairs is under pressure. if you do not have a workable ck valve it will go back down stairs. PERIOD!!!

no amount of high loop will stop it.

frodo said:

the water from down stairs is under pressure. if you do not have a workable ck valve it will go back down stairs. PERIOD!!!

no amount of high loop will stop it.

Click to expand...

cool , can some device which can release pressure introduced in this scenario then? but i am serious, I want to refrain from using ck due to hard water which damaging it frequently.
Plumber has actually introduced vent pipe if you see, not sure why it not working. may be its size & position is not appropriate.I am curious on these aspects.

you sure are hard headed. if you are going to post about a problem then take the advice that is given. fix the damn check valve. because if you knew what you were doing you would not be in this room. me personally i would rip that trash out and start over but to each there own. if this forum is not answering your question then maybe go log in to i know everything forum.

this will stop it

http://www.supplyhouse.com/Febco-0124522-3-805YD-Double-Check-Valve-Assembly-Lead-Free

journeyman said:

you sure are hard headed. if you are going to post about a problem then take the advice that is given. fix the damn check valve. because if you knew what you were doing you would not be in this room. me personally i would rip that trash out and start over but to each there own. if this forum is not answering your question then maybe go log in to i know everything forum.

Click to expand...

Ah I see, obviously I don't know everything so i believe i am in right room.I am not plumber (don't have any experiences on field like members of this forum) so I wanted to make sure This problem can not be solved by any simple solution(there may be ,after all its failing on physics principles) and the simple solution keeps me changing the ck every time it malfunctions.
(here I am talking about the ck which was outside instead of loop,the inside ck though it is misfitted i dont have concerns with it )
Besides arguments

Is following thought correct?

If I install simple air release valve , on the *top of loop* (horizontal plumbing) available at out side window, when air gets sucked from downstairs (low pressure) and pulling along the water with it passing through loop, what are the chances air will be released from valve and breaking the air pressure which would stop water being pulled along? but at same time I would need water from upstairs (i.e main line ) so to fill tank again

p.s - I am looking this problem as case study.

......................

I don't think anybody really understands what it is you're trying to accomplish.
I know I don't. I sort of, kind of do but I am not familiar with this type of water system. But I would like to know a little more about it.


These are assumption I will make based on what I read.
The line coming from the wall is the supply line with the red valve handle. That is the same line outside that you put a loop on hoping to stop water from draining down to another tank in the unit below you.
You have intermittent water pressure that fills your tank. The tank is used for when you do not have water pressure coming into the unit.

Does this supply connect to both the top of the tank and the bottom?
Where is the top line going?

How does this tank feed your fixtures that use this water. Does it flow from the bottom line back into the supply line ( red valve coming from wall )? Not with a check valve in the way.
The bottom line having a check valve so the water can't flow out of the tank, or only into the tank?
What stops the tank from over filling when you do have water pressure coming in. is it a manually filled?

So I looked at the picture again. I like puzzles. and made a sketch.
the line outside comes into the wall under the window? Yes.
Not the same as the one coming into wall inside to tank.

are there fixtures between the line going into the wall and the line coming out of the wall to the tank?

Trying to understand how this system works to better give you some ideas to work with.

Curious as to what part of the World are you located?

David, this is what i THINk he has,

Thanks Mr_David

Hussh, finally you have got it all right.



The fact is I have given input & output to A (see image) is I want to use the water from inside tank, as water is not available at all time in building's Main tank.and point A is circulated within apartment internally.

So when water in Main tank available I fill inside loft tank.

As frodo pointed regarding inside ck which is not positioned right. the ck is also damaged , which causes tank to be filled from that direction also,which i am ok with, I have valve before it to control whether tank should be filled(or used when main tank dont have water ).

Yesterday only, plumber have installed air release valve at point B. which is i think working as per thought i assumed . still I will test this couple of days more.
So as of now when main tank has no water , level 2 also don't get water from my unit's tank

Again thanks for taking time to understand the situation.cheers

Yes I am from India. knowledge don't have barriers of country borders.

I will surely update on this thread where system works.fingers crossed.

You had any thoughts?

http://www.globalindustrial.com/p/plumbing/pumps-circulators/units/gf-up15-42f-circulator-water-pump-59896155-cast-iron-115v-125-hp?utm_source=msn&utm_medium=shp&utm_term=B1012662&utm_campaign=Circulators&infoParam.campaignId=WR

https://www.directmaterial.com/forg...rk=gdfV26558_a_7c120_a_7c4639_a_7cVCB01_d_100

these are just my thoughts, not famular with your system,,i think this will give you more pressure..


View attachment 6677

http://1drv.ms/1H3AfTT
http://1drv.ms/1JUIG6o

This is the air release valve I have now at point B .
And the system works

kebyaa said:

Hi,

2) the input & output of loft tank is given to single point to have water circulated in my apartment, so that i can use loft tank/main line water in kitchen/toilets (etc)

Click to expand...

Some where Kebyaa said water was draining down to 2nd level tank in unit below when no water is available from the Main tank on roof. What I still would like know, NOT assume, is how does the tank supply water for use in the unit. From the lower tank line? If check valve is to prevent water from draining out of tank, then how does tank feed unit. Is there a pump like in Frodo sketch? Looks like the supply line from roof tank is connected to both the top line on tank and the bottom. Fill the tank with the top line only. then bottom line supplies the unit only and should not be connected to the top line.

TO break a siphon you want to let air into the line not release trapped air.

In your sketch you have A going into building below the window and to left. Then the line coming out of wall to the tank also label A to the right of the window just as I drew in my sketch. So It's not a straight shot through the wall. Sinks and toilets are on the system between A into outside wall and A out of inside wall.
If so that's was where I got lost.
When tank on roof has water, it fills your tank. Your unit tank is air tight so when it fills does it compress the air in the tank? Does the tank fill to 100% water? ?? anytime you have water from roof tank it fills your tank? and when you don't have water supply from roof tank you use your tank. So if all water comes into your unit goes through the tank before you use it, then feed the tank from the top only and take water for use from bottom of tank only.

But if sink and toilets are between A in and A out then that may not be possible unless you reroute outside A up to top of tank. Then tank can't drain back into main because bottom of tank only goes to fixtures.

Mr_David said:

When tank on roof has water, it fills your tank. Your unit tank is air tight so when it fills does it compress the air in the tank? Does the tank fill to 100% water? ?? anytime you have water from roof tank it fills your tank? and when you don't have water supply from roof tank you use your tank. So if all water comes into your unit goes through the tank before you use it, then feed the tank from the top only and take water for use from bottom of tank only.

But if sink and toilets are between A in and A out then that may not be possible unless you reroute outside A up to top of tank. Then tank can't drain back into main because bottom of tank only goes to fixtures.

Click to expand...

1) tank is not air tight,yep fills to 100%
2) I simultaneously use water from roof tank to the unit & to fill the tank also when roof tank has water
3) I have valve to control the tank being overflowing when the tank is full & roof tank has water
4) I don't know whether to call it siphon or back flow, but i agree air should go in piping ,not released out that's why the plumber had installed vent pipe (which didn't worked ) I have keep it shut now forever.
Regarding why air release valve worked in this condition I have mentioned my thought why it could work before installing it here it is again
*If I install simple air release valve , on the *top of loop* (horizontal plumbing) available at out side window, when air gets sucked from downstairs (low pressure) and pulling along the water with it passing through loop, what are the chances air will be released from valve and breaking the air pressure which would stop water being pulled along? but at same time I would need water from upstairs (i.e main line ) so to fill tank again.*
5) The system is working guys ,its absolutely working now