How to Plumb in a Washing Machine or Dishwasher

Locating the best place to plumb in a washing machine is the first job on the list. Every washing machine needs both hot and cold water and a 13amp socket. Most machines can run with cold water supply only, but you are paying for the washing machine to heat the water for you. Do not take the hot water feed from a single outlet water heater, but most other water heating systems are excellent.

For both washing and dishwashing, you need to locate the machine as close as possible to hot and cold pipes. It is a good idea to plumb the machine close to your kitchen sink, as the machine waste must go to your foul/sewage drainage system, not your surface water drainage. Before you start any plumbing, turn off the water supply to all your taps.

Plumbing hot and cold water feeds
Start by inserting valves to take the water from your pipes to the machine. There are many types of valve. A T-piece valve handle is colour coded for hot and cold. Insert the valve into the pipe. You will need to cut out 18mm of your feed pipe. Clip a pipe slice onto the pipe and turn to cut. Clean the pipe thoroughly until you only see copper. The hose from your machine screws onto the centre section of the T-valve. The T-valve handle turns the water on and off.

Place the nuts and olives from the T-piece valve over each end of the cut pipe. Once inserted the valve needs some "give" on the pipe. Tighten the nuts onto the pipe, compressing the olives into the valve. Ensure that the black rubber washer is inside the plastic nut of the washing machine hose Screw the hose onto the outlet of the T piece valve.

If your washing machine is further away, you may have to insert an ordinary T piece. Instead of the hose going on the T, fit another copper pipe to take the water to the appliance. Add a valve to the end of this pipe to connect your machine.

There are other alternative valves. Have a good look at the options available in your local DIY shop. Speed fit connection valves simply push onto the end of the pipe with a lock washer inside that secures it to the pipe. The self-cutting valve clamps onto the pipe and the turning handle cuts a hole in the copper pipe. The hose is then screwed on as before.

Removing waste water
Removing the waste water from washing machine or dishwasher is easiest when you are locating the appliance close to the sink. Change the waste fitting to replace the fitting you have and fix the machine hose to the nozzle. Use a jubilee to ensure sealed joins.

Fit a standpipe to the wall if you are too far away from the sink for a standard waste fitting, or the manufacturer instructions recommend this type of waste removal. Connect to the existing drainage kitchen system, or take out through a hole in the wall.

Wastewater must pass through a trap. The waste hose from your machine goes down the standpipe and must have a gap between the end of the tube and the trap water. The waste pipe must end below the level of the grid on the drain outside.

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