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Aug 7, 2023
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Epping
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Hi - I'm not an expert but wondered if anyone might be able to assist. I've replaced an old toilet with a new one. I've used the same water inlet pipe, and have just replaced the right angled soil pipe connecter (110 at toilet end to a 97-107 connector end to existing soil pipe). It's secured down, and works OK, apart from the toilet water after flush is draining away slowly after flush, like there's a block somewhere in the soil pipe.

It's connected to the downstairs main soil pipe that also has 2 sinks, a dishwasher and bath connected. If I drop a lot of water down one of the sinks (bucket for example) then I'm getting bubbles in the toilet, and vice versa.

If anyone could point me in the right direction of how I might have gone wrong, or if it just sounds like a blockage in the main soil pipe, i'd be really grateful. Thanks!
 
Do you have a picture of the side of the old toilet

Could be an air problem
Hi this is the old toilet (not sure if this is what you meant) and I’ve included a photo of the new toilet I’ve connected
IMG_4871.jpeg
 

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No - that was sort of impossible as the soil pipe (terracotta one) was already there and horizitonal - so I just attached new connection to it.

What’s strange is that at first I bought the wrong connection, and the toilet was too far out from the wall, and it flushed absolutely fine. But I changed the connection between toilet and soil pipe to the one shown, and now I’ve got this issue.
 
What’s with the white tape? Have you created an uphill struggle? I take it the old one was ok?
 
hi Chris - the connector between soil pipe and connector pipe was only about half the width of the one I replaced, so I put a bit of waterproof tape around to make sure it didn’t leak. It’s not uphill, but pretty flat like the one I replaced. Should I try removing tape? Thanks!
 
Is the upstairs soil pipe connected to the downstairs soil pipe and then to the stack with an open vent?

Or is upstairs connected direct to an open vented stack pipe and downstairs has a separate connection to the vented stack?

Or is there no open vent at all?

If it's the first and or third and you get bubbles in the downstairs toilet / sinks when you flush then there's a (partial) blockage below / downstream of toilet / sinks, the pipe is filing up and pushing air out through any waste pipe connected to it.

It may be coincidence or you may have disturbed something left in the brown soil pipe.
 
My money is on some solidified “matter”, that was in the horizontal pipe, had broken away during the disturbance and is now causing a blockage further down.
First thing I’d do is lift a manhole or two outside and clear as necessary.
If no joy, it’s time to take out th d new loo and investigate further.
 
Is the upstairs soil pipe connected to the downstairs soil pipe and then to the stack with an open vent?

Or is upstairs connected direct to an open vented stack pipe and downstairs has a separate connection to the vented stack?

Or is there no open vent at all?

If it's the first and or third and you get bubbles in the downstairs toilet / sinks when you flush then there's a (partial) blockage below / downstream of toilet / sinks, the pipe is filing up and pushing air out through any waste pipe connected to it.

It may be coincidence or you may have disturbed something left in the brown soil pipe.
Hiya - thanks for your help. The upstairs is connected to a separate external soil pipe that was put in when we added a new bathroom. This has an open vent and is working fine.

The downs stairs plumbing still uses the old original soil pipe.

Today I’ve tried replacing the vent on the downstairs soil pipe. When it’s off completely the toilet flushes without problem. However when it’s on, I’m getting the same problem.

Does this all point to a blockage somewhere below the surface?

Thanks for your help
 
So it was loose? I think Shaun mentioned about air, maybe this is part of the cause?
I actually replaced this part today with a new one, and then put a new valve on soil pipe and still getting problems. When the valve is off completely, or when the rodding hole is open, it flushes absolutely fine. So definitely to do with air I think.
 
Does it make sense though that when this is off completely and top of pipe open, that it flushes perfectly?
Yes, I’ve had this myself on jobs I’ve attended and it’s always been a blockage/partial blockage.
 
Sorry for the late post on this but just wanted to say thanks for your help. It was a problem underground. Had a blockage underground and once fixed, everything worked perfectly. Thanks for all the help!
 

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