Slow draining bathroom sink

markc1184

Over the past 3 weeks we've had an issue with the bathroom sink taking an age to drain. At first I thought it was limescale build up in the S trap because there was a decent amount on the bends when I took it off to investigate. I replaced that, but we still have the same problem. With the trap removed I tried feeding a drain snake into the pipe but it gets as far as a bend and won't go any further no matter what I try. I've also tried various different unblockers but no joy. If anything, I think it got worse after using one that was like chrystals. Because of how the bathroom is laid out the pvc waste pipe comes off the sink and travels under the bath behind the panel and into the larger waste pipe along with the bath. There are no pipes on the external wall to remove and try to unclog from that end.

Is it a case of having to replace the run of pipe like for like that is there at the minute? What's there is joined together using plumber solvent, is it best practise to replace this way? Is this a job that could be taken on by a DIY'er? I've given up trying to get a plumber to call to fix it.

Anything else that could be tried to get it sorted?

Many thanks.

GreeBo

markc1184 wrote: »

Over the past 3 weeks we've had an issue with the bathroom sink taking an age to drain. At first I thought it was limescale build up in the S trap because there was a decent amount on the bends when I took it off to investigate. I replaced that, but we still have the same problem. With the trap removed I tried feeding a drain snake into the pipe but it gets as far as a bend and won't go any further no matter what I try. I've also tried various different unblockers but no joy. If anything, I think it got worse after using one that was like chrystals. Because of how the bathroom is laid out the pvc waste pipe comes off the sink and travels under the bath behind the panel and into the larger waste pipe along with the bath. There are no pipes on the external wall to remove and try to unclog from that end.

Is it a case of having to replace the run of pipe like for like that is there at the minute? What's there is joined together using plumber solvent, is it best practise to replace this way? Is this a job that could be taken on by a DIY'er? I've given up trying to get a plumber to call to fix it.

Anything else that could be tried to get it sorted?

Many thanks.

Is the bath also slow draining?

markc1184

GreeBo wrote: »

Is the bath also slow draining?

No the bath along with every other sink in the house drains fine.

GreeBo

markc1184 wrote: »

No the bath along with every other sink in the house drains fine.

Have you tried an old fashioned plunger?
Or one of the ones that forces water down the plug hole?

I'd be trying all sorts of drain unblockers, foams, dissolvers before I started taking the pipe apart.

Make sure you dont mix them however, you dont want to create chlorine gas!:eek:

Note that you will need to leave some of them for a good while to dissolve the blockage.

Is there a cover on the plug hole to stop large objects getting washed down? (I'm thinking Lego bricks etc)

Alun

GreeBo wrote: »

Or one of the ones that forces water down the plug hole?

https://www.woodies.ie/plungers-suction-pump-for-sink-and-bath-drain-bomb-336186

GreeBo

Alun wrote: »

https://www.woodies.ie/plungers-suction-pump-for-sink-and-bath-drain-bomb-336186

Thats the one, couldnt think of the name!

markc1184

Yes I tried a plunger and no difference. I'll pick up one of the drain bombs tonight and give it a go.

peter bermingham

mister muscle sink and drain un blocker its mighty stuff

jonon9

When using the plunger make sure you block the overflow hole with a wet rag, it makes sure the pressure is going down the trap not forcing its way up the overflow.

my3cents

http://www.topline.ie/cleaning-storage/cleaning/cleaning-chemicals-drain-cleaners/cleaning-chemicals-drain-cleaners/douglas/instant-drain-cleaner-500ml or any of the other sulphuric acid drain cleaners.

CJhaughey

Lots of fairy liquid will move most stuff, it breaks down oils and lubricates the rest.

markc1184

I bought one of the drain bombs last night and spent a good hour trying to shift the blockage and then emptying the standing water from the sink. I ended up replacing about 2 metres of pipe altogether today. The amount of crap inside was unbelievable. Water is running through it perfectly now. Thanks for the above suggestions. Hopefully I won't need them again anytime soon.

Richard88

When you say it got worse after “using the crystals”, I presume you’re after putting something like caustic soda in there?

If that is the case and you didn’t dissolve the caustic soda or didn’t dilute it enough then yes it can definitely make the blockage worse. It turns into a solid cement like substance.

My advice: mix a good bit of caustic soda in cold water, stir it up and pour it down the drain (with the s trap connected) leave it about 30 min and then pour 2 kettles of boiling water down....

Hopefully it works for you. A lot of them ready mixed drain un blockers can be crap.

GreeBo

markc1184 wrote: »

I bought one of the drain bombs last night and spent a good hour trying to shift the blockage and then emptying the standing water from the sink. I ended up replacing about 2 metres of pipe altogether today. The amount of crap inside was unbelievable. Water is running through it perfectly now. Thanks for the above suggestions. Hopefully I won't need them again anytime soon.

What was actually inside?
Wait it hair based?

You may have an issue with the flow due to insufficient drop on the run of waste pipe (it sounds like its a long run)
Can you shorten the length of vertical pipe from the s-bend to increase this?

There shouldnt be anything going down a hand basin that would cause it to clog like this.

markc1184

There was a lot of hair and a greyish black sludge that looked to have hardened. From the bottom of the trap there is a 6.5 inch vertical drop onto a 45° angled coupler, another 3 inches onto a 90° bend which runs along the wall. The rest then is a straight run with a fall of about 1 inch towards the large waste pipe under the bath. Everything was replaced exactly as it was, which was originally installed by a plumber around 15 years ago.

EDIT. The blockage was in a small section on and just after the 90 bend. I replaced the amount I did just for my own sake and to use up most of length of pipe I'd bought.

sbsquarepants

markc1184 wrote: »

Yes I tried a plunger and no difference. I'll pick up one of the drain bombs tonight and give it a go.

I have one of these at home - they're brilliant.

GreeBo

markc1184 wrote: »

There was a lot of hair and a greyish black sludge that looked to have hardened. From the bottom of the trap there is a 6.5 inch vertical drop onto a 45° angled coupler, another 3 inches onto a 90° bend which runs along the wall. The rest then is a straight run with a fall of about 1 inch towards the large waste pipe under the bath. Everything was replaced exactly as it was, which was originally installed by a plumber around 15 years ago.

EDIT. The blockage was in a small section on and just after the 90 bend. I replaced the amount I did just for my own sake and to use up most of length of pipe I'd bought.

How long is the run with the 1 inch drop?

markc1184

GreeBo wrote: »

How long is the run with the 1 inch drop?

It's a run of 1.4 metres and it's actually a drop of 1.6 inches. Should it be more of a fall?

my3cents

markc1184 wrote: »

It's a run of 1.4 metres and it's actually a drop of 1.6 inches. Should it be more of a fall?

Thats plenty provided the pipe can't sag when full and create a low spot. In old money I'd be happy with a quarter of an inch per foot. So an inch drop every 4 feet and you have a greater fall than that.

Hopefully a plumber can state any recommendations/regulations that apply?