Actually plumbing in a washing machine comes under plumbing. So it’s not a topic covered by Whitegoodshelp. The drain hose should be fitted according to the washing machine’s manual. If you don't have the instruction manual you might be able to download one here – instruction manuals for white goods appliances.
Having said that, this page offers additional advice not covered by the manuals.
Sink
At the most basic level a drain hose can be hooked over a sink. This requires no plumbing in. However, it’s not ideal at all. If something (eg. a dish cloth) fell into the sink, or if a washing up bowl was left in, then the sink hole could get blocked.
This would result in the water flooding over the top of the sink. Also if the drain hose somehow fell off the sink you would have a serious flood. If left unattended the washing machine would continue to fill trying to make up the lost water. It would never stop filling and flooding until stopped.
So clearly a drain hose needs to be attached properly and permanently into the plumbing.
Drain hose
Washing machine drain hoses have traditionally been pushed into a standpipe, which was just a grey or white plastic tube that went through the outside wall and pointed into an open grate.
But this method has fallen out of fashion. Most washing machines are now plumbed into a u-bend under a sink. Plumbing into the u-bend is considerably easier and cheaper.
The drain hose now pushes onto a spigot, which in turn screws onto the u-bend. The spigot is usually tapered. If you push the drain hose onto it as firmly as possible it should fit quite snugly.
However, in order to ensure that the drain hose does not leak or come away completely you need to secure it with a jubilee clip or a cable tie. If using a jubilee clip be careful about over tightening. Obviously if you are clamping a metal band over plastic it will crush the plastic if tightened up too much.
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Plumbing the drain hose properly
After making sure that the drain also securely fixed to the plastic spigot you can screw the spigot onto the U bend. Make sure you don’t cross thread, which is easily done with plastic threads. The most important thing to ensure now is that there is not a direct run from this drain hose down into your washing machine.
This is because if there is a direct run down from the drain hose you can get water from the sink running down into the washing machine. This can cause water to build up in the drum.
Drain hose not long enough?
The drain hose on a new washing machine is quite short. It’s only long enough to fit right in front of the waste water pipe, or right next to the sink if plumbed into a u-bend. This is fine for most people.
But many people need to install their washing machine further away. So the drain hose is way too short. So if your drain hose is too short you can either replace it with a longer one (typically 2 or 2.5 m) or you could extend the current one using a drain hose extension kit. Try my affiliate Ransom Spares for drain hoses and extensions.
This is the second article on installing a washing machine. If you haven’t seen the first part which looked at the basics and then concentrated on fill hose related advice check it out here – How to install a washing machine. This article just looks at how to install the drain hose.
More information and advice on installing a washing machine
- Connected washing machine but now it just constantly fills with water and goes down the drain
- If you connect a washing machine in a new house and the washing machine won’t drain the water
- Aqua stop hoses for washing machines & dishwashers (What is an aqua stop hose and do you have to use it?)
- Washing machine is a hot and cold fill, but I only have a cold water supply
- What should I do with the old hot water tap when connecting a cold fill washing machine?
- Why you should not connect a cold fill washing machine to the hot water supply
Anthony Rudge says
Hi Andy,
We have a Bosch WAE24166/GB which due to kitchen renovation has ended up further from the drain and will require an extension. I am a little dubious about joined hoses so am looking at a 3.5M hose. However that particular hose includes a warning about checking outlet sizes [22/29mm] before buying which I am unable to do at the moment. Could you please advise if these sizes are compatible with my Bosch water pump..
Regards
Andy Trigg (Whitegoodshelp) says
Hello Anthony, as far as I’m aware the sizes are to do with fitting on u-bend plumbing under the sink. They should fit all pumps. If your drain hose slots into an old style stand pipe you can ignore the measurements. If it pushes onto a tapered connector (spigot) under the sink the size might be significant although if tapered it will hopefully fit. The scenario you don’t want is where the rubber on the end of the drain hose is too wide to snugly fit. Even then though, yu may well be able to cut off the rubber section and push the actual plastic drain hose onto ta tapered spigot. However, you may need to use plumbers tape and/or a jubilee clip to make it watertight. There are a variety of different universal drain hoses here of varying lengths washing machine hoses including drain hoses