bath waste pipe hopper overflowing

[nigelad]

Hello
Looking at other houses in my area, it seems that there should be a hopper below my bath, sink and shower waste pipe, where it exits the outside wall. The previous owner had instead connected this 40mm pipe to a standard down pipe, using silicon seal to fill the mismatch in pipe size. The down pipe goes straight to a gully. The plugholes always smell of drains in the bathroom.

So last week I bought a hopper and installed it below the waste pipe, on the top of the down pipe. The drains smell has now gone away. However, when I empty the bath, the hopper overflows badly. I've checked and it's not blocked.
Is the position where the waste pipe enters into the hopper critical? I could adjust that so it is exactly above the down pipe opening. Or is there anything else I can do?
I got the hopper from Wickes and it is approx 25cm by 8cm. I've seen ones the same size fitted on other houses in the area.
Ta for any advice

 

[HERTS P&D]

You have a blocked gulley.
The downpipe that goes into the ground which goes into the gulley.

Can you remove the downpipe?
Are there any manholes near by?

Andy

 

[nigelad]

Cheers Andy.

Downpipe is emptying into gulley no problem - it ends just above the grid.
Grey water from dishwasher and washing machine feed into it and also drain no problem.
It just seems like the rate the bath drains is so fast that the hopper can't cope.
There is a manhole about 3 metres away BTW.

 

[HERTS P&D]

So the gulley is draining away and not overflowing.

The hopper only over flows when the bath is emptying?

The problem could be that the waste pipe from the bath that goes into the hopper needs to be extended more into the hopper.

If you could post a picture of the pipe work in the hopper that would help.

Andy

 

[nigelad]

The hopper only over flows when the bath is emptying?

Andy

Yes.
I'll take a photo and post it when I get home.

thanks for reply.
nigel