Installing a dishwasher

How do you install a dishwasher? We’ll guide you through the steps from preparation to plumbing…

It’s the unsung hero of any home, saving arguments about who’s doing the washing up, as well as sometimes having the dishwasher deal with unusual things!

As with any appliance, if you’re not confident about installing it, especially if it involves plumbing or electrics, it’s best to get in a professional. But if you have some experience with installing a dishwasher, or other major appliances like washing machines, it is possible. The main thing to do is be prepared, read instructions thoroughly and take your time with the fixtures and fittings. Rushing can lead to some making a manageable job more work than it needs to be!

Preparing to have a dishwasher fitted

If you’re replacing an existing dishwasher, this part is slightly simpler as you will already have connecting pipes and waste pipes in place. However, if you’ve not had a dishwasher installed before, or you’re moving a dishwasher to another part of your home, it’s going to be a bit more involved as you’d expect.

Take your time to find exactly the right place for installation. The first thing to check is the dishwasher is going on a level and firm floor and preferably against an exterior wall. This is so the waste pipe won’t have to run through an internal wall. Think about any doors that will need to open around the dishwasher, or if it’s obstructing cupboards and other access to panels or sockets.

If there’s a need to add a new power socket, do speak to an electrician before moving any wiring.

How to connect a dishwasher

If you’ve found exactly where you want to install the dishwasher, it’s time to read the manufacturer’s installation instructions to the letter. Give yourself time to read through and familiarise yourself with the steps so there are no awkward surprises down the line.

If your dishwasher needs a hot water supply, you will need to ensure that the hot water pressure is high enough, especially if you’re fitting the dishwasher upstairs. A plumber will be able to advise here. If you are planning on installing a dishwasher on another floor, do speak to the plumber before you start – you don’t want to start shifting the plumbing if installation isn’t feasible.

Although you’ll have a stack of packing material around the appliance, you might have supportive packing materials inside too. Make sure you have all of this cleared up and out of your way. Keeping the area clear will help to make sense of what you’re doing without unnecessary clutter. Now follow the instructions on fitting the dishwasher, step by step.

Dishwasher plumbing

As previously mentioned, if you’re simply replacing another dishwasher, the hot and cold water pipes can be attached in place on the new machine. The blue valve is the cold water supply, the red valve is for hot water. These valves allow you to turn off the water supply if any maintenance is needed.

Your dishwasher will also need a waste outlet, which is through the flexible waste hose. There are two options:

Dishwasher drain hose through sink

To have your sink as a drain outlet for your dishwasher, you will need to change the section of the pipe that’s a sink trap and switch it out with a dishwasher trap (this is also used for washing machines). This trap has a specific inlet for a waste hose.

Dishwasher waste outlet to drain

It’s not always possible to connect directly to the sink because the dishwasher is just too far away or in a different room entirely. If this is the case, you will need to connect the dishwasher to a vertical waste pipe instead. This pipe is connected to your home’s sewer system. All you need to do is push the pipe from the machine into the top of the waste pipe. If you don’t have one, you can get a waste outlet pipe kit from a DIY store.

This overview should give you better insight into fitting a dishwasher yourself, however it’s always advisable to contact a plumber (and electrician if necessary) for further advice.

Check valves for dishwasher

The last step is to check your fittings. To do this, turn on the hot (if connected) and cold supply valves. This will enable you to check for any leaks. If you’re satisfied that the fittings are all secure, plug the machine in and run a test wash. This will also let you check the valve for the dishwasher drain line. If it all goes as planned, you’re good to go and you can set your dishwasher against the wall.