This is a pretty easy job for any keen DIY enthusiast as all you need is to connect the water supply going into the machine and the drainage for the water coming out of the machine.
So the first thing you should consider is the placement of the machine - Next to the sink is ideal as it gives you easy access to existing supplies and drainage.
Connecting The Water Supply Machines either have a Hot & Cold feed or just a cold feed ( most dishwashers just have a cold feed ) Subject to satisfactory water pressure ( check your manual ) most machines are designed to run straight from the mains water pressure - you may have problems if you have a short vertical run from a water tank supply.
Washing machines and dishwashers have standard fittings ( which should be supplies with the machine ) and use ¾ inch BSP flexible hose or hoses.
First of all you need to fit an inline valve for the hose to connect to - this is so the supply can be isolated when required.
When connecting to the mains an inline valve with a Check Valve incorporated into it should be used for connection directly into the mains - this prevents any flow back of water.
The inline valves are pretty standard for connecting to 15mm copper pipe and come in various styles These are compression fitting valves - a straight, an elbow and a Tee.
With Red or Blue control knobs for either hot or cold water supply.
You could also use a push on valve or a self cutting valve.
The Pipe Work The Pipes need to be run close to the washing machine or dishwasher so that the hose / hoses can be fitted without being pulled tight - ideally forming a slight loop.
The hoses are usually supplied in a 1.
5 metre length.
Disconnect the water supply and drain down then connect the pipework where required - make sure you have a bucket and cloths to hand because there may well be some water left in the pipes.
If the existing pipe work has compression fittings then just disconnect these and add the extra pipe using new compression fittings such as a tee fitting.
This can often be done without the need for cutting pipes.
If your existing joints are solder joints then you will need to cut the pipe to insert your required fitting.
Make sure that if you are using solder joints again then the water level is well below the level of the joint you are soldering so a good solder seal is made and that the taps are left open so no steam builds up - or you can simply use a compression or push fit fitting.
If your pipe work has push fit couplings then these can be easily be taken apart and the pipework usually re-used to make up the new pipe work - just changing your coupling to a Tee.
Make sure the new pipe work is secured to the wall with pipe clips - making sure your new valves are securely held in place.
Waste Water Drainage Using Your Sink Waste Trap If your washing machine or dishwasher is positioned close to your sink then you might be able to use your existing sink waste trap to plumb into - you may well be able to plumb the waste water hose straight into the side or top of the trap ( depending on what type of sink trap you have ) or you may be able to change your existing trap to one that would accommodate the hose as shown in the picture below.
If you have to change the existing trap then make sure that you do not use a trap where the spigot for the waste water is in the bend as this can case the machine water to be siphoned out of the machine - But do make sure that the top of the waste hose is higher than the waste water trap - a screw in the wall at an appropriate place can sort this out.
Using a Dedicated Waste Water Outlet.
If your machine is too far from an existing trap then you will have to make a dedicated outlet.
This is a vertical pipe with the water trap at the bottom of the pipe - you will then need to connect this to your existing foul water system - this is the same as your sink, bath and toilet water drainage.
It can not simply be fed into a rain water soakaway.