Continuous stream of water in waste pipe

[plumber_n00b]

Hello,

I am a homeowner and new here. I have a mysterious (for me) issue related to my house plumbing system. Recently (a few months ago) I noticed that there is a constant stream of water in waste drain pipe of my plumbing system. The stream of water in the waste drain pipe only stops when I close the mains. In the last few months, my water bill has jumped up significantly. I am unable to understand why is there so much water running through the waste drain pipe when, no taps are being used in the house.

Below, I have attached a picture of my plumbing system highlighting a few points

1. The waste drain pipe which has a constant stream of water, regardless of usage in the house
2. Grundfos Selectric UPS2 15-50/60 130 pump. This used to be on, with a control switch. I have not seen it on for months now. Not sure if this is related to the issue in point 1
3. Pipe through which I can feel the water flow to the waste drain pipe
4. Water software in my plumbing system so all the water to the house flows through the water softener.

I would like to know why is this happening? I hope someone can point me into the right direction so that I know what to investigate.

Thank you for your help.
Andy

 

[Riley]

You need a g3 engineer to look at it

 

[Harvest Fields]

There is definitely a leak somewhere. I would get a pro out if you cannot see it. Had a good mooch around though just incase.

 

[plumber_n00b]

There is definitely a leak somewhere. I would get a pro out if you cannot see it. Had a god mooch around though just incase.

Thanks for your reply. Apologies for the stupid question but why does this stop when I turn off the mains if there's a leak?

 

[Harvest Fields]

Because it is on your cold/hot (if balanced) supply pipework somewhere.

 

[Brambles]

Don’t leave it too long before getting it attended to - any failure / blockage in your drain line, will result in a real mess.

As stated earlier you must use a G3 Engineer to work on the UV system

 

[plumber_n00b]

Don’t leave it too long before getting it attended to - any failure / blockage in your drain line, will result in a real mess.

As stated earlier you must use a G3 Engineer to work on the UV system

Thanks for your reply. Sorry, but what is UV system?

 

[Harvest Fields]

Unvented

 

[ShaunCorbs]

Looks like air source or solar guys

 

[Harvest Fields]

I was just explaining what UV meant mate.

 

[Brambles]

Andy,

For clarity, the Dimplex Cylinder is an Unvented Cylinder with a buffer store - as Shaun said usually used with a “renewable energy” system. You will know what your system is.

This is not a system to “tinker” around with.

My assumption is that the relief valve on the combination valve, has been operated (or been fiddled with) and is now stuck open, but it may be more complicated than that. I say that (the latter) because in your detailed explanation you have not said that you can see water flowing through through the black tundish. The tundish is at the far end of your line 1 (green) on the back wall of your cupboard, below the white control panel.

Suffice to say, continuously running water in a relief valve drain line is not a good thing. It can only ever leak!

To work on the part of your system that is Unvented (ie. pressurised) you need a G3 qualified engineer. My advice would also be, to work on any part of your system you should use someone who is conversant with hear pimp systems.

From what you say ( from where you think the water is coming from ) it appears to be a relief valve issue. However, you may be mistaken in your location and it could possibly be the water softener. The recharge valve may not have completed a full sequence and is stuck in the open position - that could give you continuously running water through the mol sieve catalyst. To test for this, isolate the water softener (inlet and outlet) and open the bypass valve. If the running water stops with the bypass open and the inlet / outlet closed it is a softener fault.

A final point - has the water softener recently been installed? The installation of it looks to be of a far lower quality that the rest of your system. Apologies if that sounds rude.

 

[ShaunCorbs]

I was just explaining what UV meant mate.

Would say it’s a thermal store

 

[Harvest Fields]

Would say it’s a thermal store

Missing my point mate. He asked what UV meant. I didn’t comment on the cylinder myself as I haven’t seen one like that before.

 

[Burger]

Try turning what appears to be your filling loop off, don’t need to be G3 for that. (Circled yellow).

 

[Harvest Fields]

Wouldn’t say that was a filling loop mate. But I could be wrong.

 

[Stigster]

He's highlighted the continuous flow of water at the tundish so it's got to be coming from the cylinder whether that's a thermal store or unvented cylinder, unless there's another type of system there that uses a tundish that I don't know about. We could do with more pictures of where the pipe connected to the top of the tundish goes.

 

[Millsy 82]

You need a g3 engineer to look at it

Although you are 100% right I think just say you need someone qualified to touch an unvented cylinder.

Saying G3 will just confuse the customer and you dont say get a cenwat engineer for a boiler.

 

[Brambles]

This must be getting a bit confusing for Andy.

The cylinder / store is either a Dimplex ECS or an EAU, both are quite complex, one is unvented and the other isn’t - It is hard to tell from the photo which it is.

The comment about the filling loop from CBW is probably incorrect. The valves on the flexibles on the are almost certainly the I/O for the water softener - the third valve being the manual by pass.

 

[Millsy 82]

Wouldn’t say that was a filling loop mate. But I could be wrong.

My guess would be something like a water softener because you have a bypass valve in between the 2.

 

[Riley]

This must be getting a bit confusing for Andy.

The cylinder / store is either a Dimplex ECS or an EAU, both are quite complex, one is unvented and the other isn’t - It is hard to tell from the photo which it is.

The comment about the filling loop from CBW is probably incorrect. The valves on the flexibles on the are almost certainly the I/O for the water softener - the third valve being the manual by pass.

Well a G3 qualified engineer would cover all bases as it serves vented and unvented

 

[ShaunCorbs]

Well a G3 qualified engineer would cover all bases as it serves vented and unvented

Don’t need to be g3 with a thermal store

 

[Riley]

No but I’m saying G3 covers all bases and will be (hopefully) familiar with the workings of safety devices.

 

[Gasmk1]

Try turning what appears to be your filling loop off, don’t need to be G3 for that. (Circled yellow).

View attachment 39256

pump connections

 

[plumber_n00b]

Try turning what appears to be your filling loop off, don’t need to be G3 for that. (Circled yellow).

View attachment 39256

Thanks for your reply. The bits that you've circled in yellow are the inlet (from mains) and outlet (to the house) for the water softener (4) in OP

 

[plumber_n00b]

Andy,

For clarity, the Dimplex Cylinder is an Unvented Cylinder with a buffer store - as Shaun said usually used with a “renewable energy” system. You will know what your system is.

This is not a system to “tinker” around with.

My assumption is that the relief valve on the combination valve, has been operated (or been fiddled with) and is now stuck open, but it may be more complicated than that. I say that (the latter) because in your detailed explanation you have not said that you can see water flowing through through the black tundish. The tundish is at the far end of your line 1 (green) on the back wall of your cupboard, below the white control panel.

Suffice to say, continuously running water in a relief valve drain line is not a good thing. It can only ever leak!

To work on the part of your system that is Unvented (ie. pressurised) you need a G3 qualified engineer. My advice would also be, to work on any part of your system you should use someone who is conversant with hear pimp systems.

From what you say ( from where you think the water is coming from ) it appears to be a relief valve issue. However, you may be mistaken in your location and it could possibly be the water softener. The recharge valve may not have completed a full sequence and is stuck in the open position - that could give you continuously running water through the mol sieve catalyst. To test for this, isolate the water softener (inlet and outlet) and open the bypass valve. If the running water stops with the bypass open and the inlet / outlet closed it is a softener fault.

A final point - has the water softener recently been installed? The installation of it looks to be of a far lower quality that the rest of your system. Apologies if that sounds rude.

Thank you so much for such a detailed reply. I understood most of it (due to lack of understanding about all the plumbing terms). Will go home and do another diagram to clarify some of the points raised in your reply.

To your final point - no, the water softener was installed more than 3 year ago. This issue only started a few months ago. Something I forgot to mention (and you just reminded me), I installed an under-the-sink RO filter few months ago. Yikes! Could that be an issue?

Although, after I noticed the water stream, I have turned the RO system off and haven't used it in the past few months since this started. So I am not sure how the two could be related as there is no water passing through the RO system at all.