Blocked soil pipe after installing replacement toilet

[Ben-gee]

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.

 

[AntEpping]

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

 

[AntEpping]

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.

 

[Deleted member 120897]

So definitely to do with air I think.

Valve? As in air admittance? If yes, definite blockage, not air related.

 

[AntEpping]

Valve? As in air admittance? If yes, definite blockage, not air related.

Yes - air admittance.

Does it make sense though that when this is off completely and top of pipe open, that it flushes perfectly?

 

[Deleted member 120897]

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.

 

[ShaunCorbs]

Yep blockage if you flush enough it will start to back up

 

[AntEpping]

Yes, I’ve had this myself on jobs I’ve attended and it’s always been a blockage/partial blockage.

Thanks Chris

 

[AntEpping]

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!