Extending sink overflow pipe a tiny bit

[Soong]

I had to adjust the down pipe slightly from the sink overflow to fit a vent pipe. This has meant there's an inch gap between the two.

What can I buy that will be the quickest/best way of having them join again? Previously the sink pip just poked into the down pipe. I assume that's normal and fine?

 

[Madrab]

A sink overflow would normally connect into the bottom of the sink waste with a piece of corrugated pipe and not usually a separate pipe like that, are you sure that's a sink overflow and not say a condensate pipe from the boiler?

If that is just an open ended 45deg coupler then a piece of 21.5mm overflow pipe would be glued into that.

FloPlast Overflow Pipe White 21.5mm x 3m - Screwfix

Order online at Screwfix.com. A 21.5mm solvent weld overflow system in white PVC-U. No expansion gap required on the solvent weld overflow system. Apply solvent cement evenly to both surfaces of joint, insert pipe fully in the socket depth and remove surplus cement with a cloth. Allow five...

www.screwfix.com

 

[Soong]

A sink overflow would normally connect into the bottom of the sink waste with a piece of corrugated pipe and not usually a separate pipe like that, are you sure that's a sink overflow and not say a condensate pipe from the boiler?

If that is just an open ended 45deg coupler then a piece of 21.5mm overflow pipe would be glued into that.

View attachment 322638

FloPlast Overflow Pipe White 21.5mm x 3m - Screwfix

Order online at Screwfix.com. A 21.5mm solvent weld overflow system in white PVC-U. No expansion gap required on the solvent weld overflow system. Apply solvent cement evenly to both surfaces of joint, insert pipe fully in the socket depth and remove surplus cement with a cloth. Allow five...

www.screwfix.com

You're right - cheers. Just had another look and it's the boiler condensation pipe.

Can I just use some tube like the one from my washing machine out pipe and just use a screw clip to attach it to some hose that I stick down that pipe?

 

[BlueLoo]

Where is it (larger pipe) going to?
Is this a trapped entry to the drains or just a pipe sticking out the wall?

Seems odd to have it open ended.

 

[BlueLoo]

You're right - cheers. Just had another look and it's the boiler condensation pipe.

Can I just use some tube like the one from my washing machine out pipe and just use a screw clip to attach it to some hose that I stick down that pipe?

I would think this should be open ended if so?

You wouldn't want to create a syphon block on this line?

 

[Soong]

Where is it (larger pipe) going to?
Is this a trapped entry to the drains or just a pipe sticking out the wall?

Seems odd to have it open ended.

Goes into the waste pipe of the sink.

 

[Soong]

I would think this should be open ended if so?

You wouldn't want to create a syphon block on this line?

I mean attach the hose to the top pipe and have it open ended into the bigger pipe below. Hopefully that's ok as that's what our builders did! Just without the hose.

 

[BlueLoo]

Goes into the waste pipe of the sink.

Curious.
How does this not backflow when you empty the sink?

 

[Soong]

Curious.
How does this not backflow when you empty the sink?

No idea! I've taken a photo out of curiosity so hopefully it shows how it doesn't backflow and I haven't just been extremely lucky in not having the kitchen flood all this time. Can you tell by looking at it?

 

[thomp1983]

Pipe marked in orange appears to have a compression connection at the bottom, unscrew it and replace the pipe with a longer piece so it reaches

 

[BlueLoo]

Er.

Googling, suggests the clamp is this:

McAlpine Condensate Pipe Clamp Grey - Screwfix

Order online at Screwfix.ie. Condensate pipe clamp to suit 1¼" / 1½" pipe. Receives the discharge from a condensing boiler. Universal connections for 19 / 23mm rigid pipe and 25mm flexible pipe. Manufactured in polypropylene. FREE next day delivery available, free collection in 1 minute.

www.screwfix.ie

But then, it's not been used to connect the condensation pipe, but rather a air /vacuum vent behind it.
The other side of the fitting left open for the condensation pipe.

So, er, it's back to front?

Your condenser pipe should be going to the vent inlet and vice versa.

Looks mad

I'm no plumber. Why would you have an air vent next to a open pipe?

 

[BlueLoo]

Conspiracy theory:

The plumber ****ed up on the cond pipe and couldn't be arsed doing it properly.

 

[Soong]

That clamp is for a vent pipe for a boiling water tap. That's what I just put (hopefully correctly).

Before that was there it was just the thick pipe going up to the thin pipe (boiler condensation overflow) which was just a couple of inches down into the thick pipe. And not attached, just hanging over it.

Disaster waiting to happen or normal?

 

[Madrab]

Nothing really wrong with that, it's a trapped standpipe attached to the waste run. Usually used for an appliance outflow. It'll be there to allow a location for the boiler condensate to drain into the waste and then someone's used the downpipe to attach the saddle clamp to attach the pressure release valve outlet from the boiling water tank.

Just extend that condensate pipe into the tube. It actually then incorporates an air break for the condensate, which is no bad thing.

Only concern there would be is if the waste pipe further downstream were to block then that standpipe would be the first to overflow but that isn't too unusual