HELP - all out of ideas - toilet problem

[serenity_aus]

Hi 🙂

I was hoping you could help me with a toilet problem I'm having.

I started having the water in my toilet bowl siphon out and allowing sewer gasses into my house 😱. I got a plumber out and he put down a camera and found a broken pipe with roots forming a partial blockage.

I got a plumber specialising in major sewer works and he came out and dug up the pipe and replaced the broken pipe (could not use epoxy sleeve as the drought had caused the pipes to move thus causing the roots to infiltrate). $$$. (darn thing was 10cm short of being council's problem but that's a whole nother thread 😀 )

The drain was fixed a month ago and now I'm still getting the water sucked out of the toilet bowl. Not as bad as previous (not getting to level where sewer gasses are coming in), but more frequent than before. In the past 30 days it has probably occurred perhaps 4 or 5 times.

I live on my own and work so the toilet does not get used THAT often.

I had a plumber out this morning and he has checked everything again including:

* putting hose down roof vent
* putting camera down sewer drain
* removing toilet from floor and checking everything

They've come up with nothing. Has anyone else got any ideas 😕

I know you guys have seen worse, so I won't apologise, but I attach a picture of the toilet to show what is happening. Don't worry, it's blue dye, I have no bodily functions that are that colour 😛

1. toilet after water has siphoned off
2. toilet normally


Thanks in advance.

 

[leakylea]

there may be a blockage that builds up and then frees itself further down the line, this can result in the drain pulling like this,how has the drain been relpaced?

 

[serenity_aus]

there may be a blockage that builds up and then frees itself further down the line, this can result in the drain pulling like this,how has the drain been relpaced?

See my above post. The drain was dug up and replaced. AFTER this I still have problems and subsequntly another camera has gone down (all the way to the main council sewer line) and there is no blockage. The council has not had any reports from any other resident so it can't be in the main council sewer. 🙁

 

[John Flower]

Check the way that the rest of the soil system in your house has been plumbed in, it possibly could be caused by bad design of a single soil stack system which is causing induced syphonage in the wc pan when other appliances are used i.e the bath ,basin ect. Normally on single stack systems the appliances are grouped closley around the stack with the wc being the closest to it .

If it is an older property with a two pipe system then if new sanitary ware is fitted sometimes the seperate vent pipe connection is not refitted (especially to wc pans) in a mistaken idea that it is not needed.

 

[Alanka]

Does the water gradually disappear, or does it suddenly disappear when another appliance, e.g. bath, other wc, sink ... , get emptied?

If sudden, it cannot be a leaky pipe. Fitting an air admittance valve to the soil pipe near the offending appliance could cure the problem. If slow, it is almost certainly a leak (but you say there are now no leaks!??)

 

[justlead1]

Hi. Does the soil / waste system extend to other households? as the syphonage can be induced by other appliances on a badly designed system.


Have you checked that the pan is completely clear as lint like material can get caught over the weir of the trap and act like a wick to empty trap.

You mention vent pipe does this pass close to the WC. or is WC. on the end of horizontal run?

Has the drainage system to which you connect (council) had a history of blocking.

Are other households experiencing similar problems? Good Luck

 

[serenity_aus]

Hi,

Thanks for taking the time to reply guys.

Check the way that the rest of the soil system in your house has been plumbed in, it possibly could be caused by bad design of a single soil stack system which is causing induced syphonage in the wc pan when other appliances are used i.e the bath ,basin ect. Normally on single stack systems the appliances are grouped closley around the stack with the wc being the closest to it .

If it is an older property with a two pipe system then if new sanitary ware is fitted sometimes the seperate vent pipe connection is not refitted (especially to wc pans) in a mistaken idea that it is not needed.

The house is approx 13 years old. I have owned the house for 7 years. The problem has only been occurring in the last 6-12 months which is why I got it a) investigated and fixed and b) investigated again. If it was a poor design I would have expected it to be a continual problem, rather one that just occurred in the last 6-12 months? OR could soil shifting cause an otherwise good design to go bad? The plumber took quite a while and investigated every inch of the pipe from my toilet to the main sewer and said there was no backflow.

Does the water gradually disappear, or does it suddenly disappear when another appliance, e.g. bath, other wc, sink ... , get emptied?

If sudden, it cannot be a leaky pipe. Fitting an air admittance valve to the soil pipe near the offending appliance could cure the problem. If slow, it is almost certainly a leak (but you say there are now no leaks!??)

It doesn't gradually disappear in that at random times I will go in there and notice the water is gone. It can happen twice in as many days, or it can happen once a week. There doesn't appear to be any consistency. Since I shower more than once a week I'm guessing there is no link 🙂 They removed the entire toilet from the floor and checked everything and couldn't find a thing. No apparent leak etc.

Sorry I can't use the technical words but if you can imagine, the toilet is on the outside wall of the house. On the roof, directly above the toilet is the air vent. The plumber also mentioned that whilst we found the problem with the roots, it didn't really explain the water being sucked out of the toilet bowl because he would have assumed that the air would have been sucked from the airvent 😕

Outside this wall with the toilet on it in the ground (concreted) is the first capped outlet. This then runs underneath across the house where there is another capped outlet - approx distance 5 metres. This then runs directly to the main sewer - approx 5 metres and a depth of 1.5metres.

Where my house meets the main sewer is the actual council manhole. They removed this manhole when they fixed the pipe. It was rusted all in but they managed to remove it but it won't sit flush anymore. I can't see/smell that it is not sealed though.

Hi. Does the soil / waste system extend to other households? as the syphonage can be induced by other appliances on a badly designed system.


Have you checked that the pan is completely clear as lint like material can get caught over the weir of the trap and act like a wick to empty trap.

You mention vent pipe does this pass close to the WC. or is WC. on the end of horizontal run?

Has the drainage system to which you connect (council) had a history of blocking.

Are other households experiencing similar problems? Good Luck

The guy from council that came out said they had had no reports. Whilst the general area is probably about 30-40 years old, the development I live in is approximately 13 years old and the main council pipes outside my house would have been laid then (13 years ago). The house I live in is a single level dwelling which has completely separate plumbing etc from neighbours. All sewer/grey water goes directly to council.

We are having severe drought problems which is what caused the pipe to crack in the first instance (the roots were the result of it finding water, not the cause). I believe the soil the pipes are in is reclaimed, but when I bought the house I had an inspection and the guy said that they had done the right thing and put a ~1 foot concrete border around my house to stabalise it. When the plumber fixed the pipe he laid it in sand first then put back the soil. I believe due to our drought problems it is a Standard that all pipes must be laid in sand.

I hope this response has helped some. I appreciate you all taking the time to try and help me work out this mystery 🙂

 

[bobpape]

Hi
Have you got a dog

 

[migoplumber]

if you havnt got dog or a cat, then it does appear to be inadequate ventilation on stack.
maybe top of vent pipe is full of crap.
try fitting air inlet trap to basin, or even an aiv to stack about a metre above height of toilet cistern.

good luck
shaun

 

[Bernie2]

Yes tend to agree with Migo. If it is pulling, why isn't it sucking in air through the vent rather than sucking out the seal?

I assume there are no birds nests in the vent pipe?

I assume the vent is properly sized?

I wonder if its the heat evaporating the seal in the hot weather?
Okay it may not happen in the UK very often, but Oz sure has been getting hot.

I once worked on a weird job that was a bit unexplained, it was found to be a tin lid down the drain. Sometimes it was flat and let water by, then it turned up and stopped the flow. The drain rods just pushed past it.

But if a camera has been down?

Its a bit of a mystery really but vent looks favourite?

Incidentally are you sure its the trap being sucked out and not blown out?

But then the vent should stop that anyway, but perhaps not completely? The vent may have an air admittance valve fitted which would not stop the seal from being blown out?

So it could be a build up of sewer gas. I imagine the drains in Oz must be running with next to no water to flush them out, and so you may get an unusual build up of gas.

 

[bobpape]

I have seen this happen in empty properties the water simply evaporates,
But tell me... does every last drop of water vanish,
Is the pan heavily scaled,
Is there a peice of string in the trap,
Slide some paper under the pan and check it next time it empties,

 

[flat pack]

Hi take some pictures of the pipes outside
and post on here..

 

[serenity_aus]

Sorry, I only just got notification there has been more posts on this thread of mine. 🙂

Hi
Have you got a dog

No, No pets.

if you havnt got dog or a cat, then it does appear to be inadequate ventilation on stack.
maybe top of vent pipe is full of crap.
try fitting air inlet trap to basin, or even an aiv to stack about a metre above height of toilet cistern.

good luck
shaun

No pets. Have had someone stick a hose right down the vent pipe with no blockage.

Yes tend to agree with Migo. If it is pulling, why isn't it sucking in air through the vent rather than sucking out the seal?

I assume there are no birds nests in the vent pipe? No

I assume the vent is properly sized? I Don't know what a "proper" size is, but it would have the Australian Standard.

I wonder if its the heat evaporating the seal in the hot weather?
Okay it may not happen in the UK very often, but Oz sure has been getting hot. I wouldn't imagine or everyone would have the problem and it would be well known? Also, it was fine for ~5years and only just begun being a problem.

I once worked on a weird job that was a bit unexplained, it was found to be a tin lid down the drain. Sometimes it was flat and let water by, then it turned up and stopped the flow. The drain rods just pushed past it.

But if a camera has been down? Yes, twice

Its a bit of a mystery really but vent looks favourite?

Incidentally are you sure its the trap being sucked out and not blown out? Before this was occurring the house was permanently shut up (always at work). I am now leaving the toilet window open so in the event that the water gets sucked out, my house won't stink up.

But then the vent should stop that anyway, but perhaps not completely? The vent may have an air admittance valve fitted which would not stop the seal from being blown out?

So it could be a build up of sewer gas. I imagine the drains in Oz must be running with next to no water to flush them out, and so you may get an unusual build up of gas.

I have seen this happen in empty properties the water simply evaporates,
But tell me... does every last drop of water vanish, No, some is left sitting in the bowl as per the photo in my first post. If it were to evaporate, surely I would see a lowering of it over time, and consistently? One minute it can be fine, the all of a sudden, next to none left.
Is the pan heavily scaled,
Is there a peice of string in the trap,
Slide some paper under the pan and check it next time it empties,

Hi take some pictures of the pipes outside
and post on here..

Will do on the weekend.

Thanks for all your posts and continued interest.