Gunk inside washing machine waste pipe

[diyyid]

Hello

Every few weeks, my washing machine (AEG, 9yrs old) spin cycle time takes ages and each time, it's due to solid gunk inside the white waste pipe under the sink.

The waste pipe is a 20mm inlet with 40mm connector (like this https://www.screwfix.com/p/mcalpine...ppliance-tee-piece-connector-white-40mm/4167p)

The gunk builds up inside the 20mm area causing a severe blockage.

Does anyone know why this happens?

If I drain the washing machine grey pipe into a bucket, the spin cycle finishes within normal time.

If I clean the white pipe, it's OK for a few weeks and then it happens again.

I dismantled and cleaned deeper under the sink (inside the trap, etc) but I can't clean any further than that.

I don't think the problem is the washing machine - does anyone know how to solve this once and for all? Is there a blockage further down the waste system requiring a plumber? Sink drains at normal speed as far as I can tell. Or something else?

Washing machine receives a regular maintenance cycle and the filter is also cleaned regularly.

 

[Mottie]

Are you using the washing powder capsules? When you say it receives a regular maintenance cycle, do you run some degreaser through it?

 

[diyyid]

Using liquid detergent and softener for normal washes.

For maintenance, I use a dedicated washing machine cleaning liquid or regular detergent (if washing machine cleaner is finished) - both on a 95c cycle.

I don't know if the cleaner has degreaser in it tbh, never checked and didn't know it was a thing.

 

[Wayners]

Used powder.
Liquid causes black slime and smells so you have to run a cleaning cycle with the magic button press (see instructions for cleaning)
Over 60c temperature will kill bacteria.

Also 9 year old machine may have a weak pump as it's old which slows up the water flow.
Swap pump is easy sometimes.
Lay machine on its side and swap pump takes 10 mins and cheap at around £40 or less so worth a punt.

New pump and switching to powder solved our machine problems.

 

[CountryFan]

Does the grey hose have the correct fall?

 

[Mottie]

Using liquid detergent and softener for normal washes.

For maintenance, I use a dedicated washing machine cleaning liquid or regular detergent (if washing machine cleaner is finished) - both on a 95c cycle.

I don't know if the cleaner has degreaser in it tbh, never checked and didn't know it was a thing.

Try a dishwasher cleaner. Try changing to powder for a while and see if it still gunks up then.

 

[jj4091]

To solve it once and for all instal it's own 40mm waste standpipe.

 

[foxhole]

Does the grey hose have the correct fall?

As mentioned likely you have hose syphoning muck from the kitchen sink if your hose is not correctly positioned .
Photo of waste would clarify .
With an old machine you get a build up of old soap in the sump which gets loosened when the machine is spinning and gets pumped to outlet.
Would be worth removal and cleaning ( I once removed six mugs of congealed soap from an old machine ).

 

[opps]

Ages ago, I had to extend my mum's washing machine waste pipe. Months later, the machine wouldn't drain.

I removed the pipe and blew into the end of it, black gunk appeared in the drum. I recommended that she do a high temperature wash from time to time. The process of blowing into the pipe was not pleasant.

You are doing the hot washes but it might be the case that you need to remove the existing gunge in the pipe that was there before you moved on to the occasional hot washes. Scrunching the pipe and doing mouth to mouth might help. Alternatively, you might be able to pour cleaning agents down the end of the hose. Ribbed hoses risk gunk building up in folds.

If the spigot is pointing upwards, I suspect that the gunge is from the pipe and not water running down the trap.

Unfortunately, the waste pipe is factory fitted. You cannot replace it with ease.

Best of luck.

 

[diyyid]

Thanks for the replies.

Used powder.
Liquid causes black slime and smells so you have to run a cleaning cycle with the magic button press (see instructions for cleaning)
Over 60c temperature will kill bacteria.

Also 9 year old machine may have a weak pump as it's old which slows up the water flow.
Swap pump is easy sometimes.
Lay machine on its side and swap pump takes 10 mins and cheap at around £40 or less so worth a punt.

New pump and switching to powder solved our machine problems.

I've never heard of this before but I've always preferred to use liquid because I've used power with other machines where the powder doesn't dissolve or leaves white streaks on dark clothes. User manual doesn't say anything specific to liquid-use maintenance. The model is L8FEE965R.

Does the grey hose have the correct fall?

I believe so - after cleaning the pipe, spin cycle runs as normal. I don't have a great deal of flexibility with the pipe and can't reroute it any way. See attached picture.

Once when the pipe was blocked, as a test, I ran the spin cycle and drained into a bucket. It pumped out water very swiftly (which caused a bit of a panic since I only had one bucket to hand!). To my eyes, it was working as expected. No solid waste was pumped out which would indicate old soap or other dirt being stuck somewhere, and this is why I think the problem is not the machine.

To solve it once and for all instal it's own 40mm waste standpipe.

It would be ideal to have a dedicated waste pipe, unfortunately not an option at this time.

As mentioned likely you have hose syphoning muck from the kitchen sink if your hose is not correctly positioned .
Photo of waste would clarify .
With an old machine you get a build up of old soap in the sump which gets loosened when the machine is spinning and gets pumped to outlet.
Would be worth removal and cleaning ( I once removed six mugs of congealed soap from an old machine ).

See attached picture of waste. Please also see my reply to CountryFan above re old soap being pumped out.

Ages ago, I had to extend my mum's washing machine waste pipe. Months later, the machine wouldn't drain.

I removed the pipe and blew into the end of it, black gunk appeared in the drum. I recommended that she do a high temperature wash from time to time. The process of blowing into the pipe was not pleasant.

You are doing the hot washes but it might be the case that you need to remove the existing gunge in the pipe that was there before you moved on to the occasional hot washes. Scrunching the pipe and doing mouth to mouth might help. Alternatively, you might be able to pour cleaning agents down the end of the hose. Ribbed hoses risk gunk building up in folds.

If the spigot is pointing upwards, I suspect that the gunge is from the pipe and not water running down the trap.

Unfortunately, the waste pipe is factory fitted. You cannot replace it with ease.

Best of luck.

Yikes, I'll can try cleaning fluids but I certainly won't be doing mouth to mouth on it, especially after seeing what came out of it during cleaning.

 

[Mottie]

That waste pipe is below the level of your sink at its highest point. Surely the sink will drain into the machine? Can you get it up higher. Here’s mine.

 

[diyyid]

Thanks, I'll give this a try and report back - it takes a few weeks for the problem to restart. I'll be kicking myself if that is the solution!

 

[foxhole]

A test as you describe would not clarify if you have a sump blockage, vibration from spinning is not guaranteed to free up any loose material, you may run the machine a dozen times before this happens.Idealy run the machine at maximum temperature at least once a month.

 

[JohnD]

Old soap residue and fabsoft forms a sludge, and stays in the machine (it also supports bacteria, which smells).

If you want to see it, put a cup full of Washing Soda Crystals in the powder compartment, and run the hottest cotton cycle, with no soap of fabsoft.

If you want you can put some old white towels in.

I bet you 50p the machine foams up with the old soap dissolving, and the towels come out softer and whiter than before.

You can do it again, until you have cleaned out all the sludge.

Most people put in too much powder.

You will get better long term results without fabsoft.

You can add a spoonful of Washing Soda to each wash for better results and to keep the machine clean. Reduce the amount of powder and buy a 50ml scoop to measure it.

Washing Soda is not aggressive or harmful like Caustic Soda, it is a different chemical.

£2 a kilo in Tesco and other supermarkets

 

[diyyid]

Thanks all for the tips and feedback.

I've been monitoring washing machine performance after raising the pipe and checked everything again today - so far no sign of any blockage. I'll continue keeping an eye on it but preliminary signs are it's problem solved. And to think the solution was so simple!

@JohnD those soda crystals look handy, I'll definitely be picking up a bag to give my machine a good clean.