waste drainage

[albie]

Hi
18 months ago we replaced old wc etc with new. Toilet flushes ok but then after a few weeks toilet waste won't flush away - this has happened 4 times now. The last time the plumbers dug up drains outside and said problem was due to a collapse near main drain away. They fixed this and put in an access chamber. (Todate we have not been billed for this work). Well, we had friends over Christmas and the problem came back. Today I opened the access chamber and it was FULL of waste paper etc etc etc. I cleaned it out and flushed all the pipes and OK again. Can anyone tell me why this is happening especially after outside was dug up and sorted. If there is a problem with angles/drops etc etc surely the plumbers who installed the new cloakroom WC should have known this when they re-positioned pipework.

(we have a lovely new cloaks and cannot use it)

Thanks,

 

[Hugh Jaleak]

If they've dug down and fitted a chamber FOC then this suggests they were aware of a problem in the first place. What pipework was repositioned and did this problem occur with the old W.C.?

Repeated blockages are sure sign of a fault in the drain, be it collapsed pipe, bad joint, backfall (pipe sloping uphill), etc, CCTV survey may be needed to determine what is going on.

 

[albie]

Hi

We didn't use the old wc very much but soil pipe etc was cast iron and all this was replaced because we were told you couldn't get fitments to fit old pipework and so replaced with black plastic piping. The new toilet was moved approx. 12 inches to another wall and a new opening was made 4 inches from old one to accommodate new soil pipe. I guess you could be right in that when digging down outside to replace pipe etc they would know or see any problems? As far as I am aware the new bathroom WC has the same drop and we have no problems with that. The problem appears to be from the new cloaks wc to the main soil drain.

So its the piping from the toilet to the main waste drain. The main drain has been in place since the 1950's and water is running freely.

 

[Hugh Jaleak]

A 'good' plumber should be able to join to the iron, skills may not be there to do the old type lead joint, but various fittings are available to connect to iron. However, it does depend on the condition of the cast iron, if time hasn't been kind to it then often proves better to replace it.

I cant see them having replaced the above ground stack in itself would give rise to a problem, concern is now having done that did they manage to drop anything (e.g. broken lump of old cast stack) down the drain..... Any existing faults with underground drain wouldn't be visible unless that section of drain was exposed. If a connection has been made to the drain just below ground level, then the condition of the rest of the run wouldn't be apparent.

It may be they've fitted a chamber as a goodwill gesture, and to access the pipe to clear it, but this may only cure the symptoms, not the cause. My advice would be to get a CCTV survey done to assess the condition of the pipes and determine further action from there.

 

[albie]

...we're talking about 3ft of underground pipework that connects to the main waste drain. Prior to cleaning I put rods down the main drain (plumbers left me some) and it was clear. I also washed water along the main waste pipe and this ran freely - the blockage in the 3ft connecting pipe didn't move. I can only assume that the problem is where the pipe connects to the main drain. When the plumbers came the last time I was told that the pipe joint to the main drain had collapsed and they had fixed it - they did have to dig thru 2ft of solid path and some concrete.

I do agree with you that the only way to sort this is to get the cameras down .....
Thanks,

 

[Hugh Jaleak]

Well, if its only 3 ft then maybe just as easy to dig down and expose the pipe(s). (It'll have to be excavated to effect repairs anyway...) I am assuming there is a 3ft run from the foot of the new stack to the line of the main? It's not a major job to replace that section provided the junction to the main drain is sound, although it could be prudent to replace the junction with a small chamber whilst the excavation is open.

Does main drain take waste from any other W.C.'s? Water may well run freely, its the solids and paper etc that cause the problems! Washing water along a straight run wont help much, connections are made obliquely in direction of flow, any water would have gone straight past the blockage!

 

[HERTS P&D]

What was it blocked with? any grease and fat?

Andy