Plumb in a dishwasher

Connect a dishwasher to your water, waste and power supply safely, checking for leaks before running a full test cycle.

PD-01Gather your tools and clear the spaceEmpty the cupboard under the sink and lay old towels down to catch drips. Check the dishwasher box for its inlet hose, drain hose and power cable — most come fitted with a plug. Have a spanner, spirit level and bucket ready before you start.

1 each · Adjustable spanner

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1 roll · PTFE tape

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2 each · Old towels

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1 each · Bucket

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PD-02Turn off the water supplyFind the isolation valve on the cold pipe under the sink and turn it off, or shut the main stopcock if there isn't one. Turn on the kitchen cold tap briefly to relieve pressure in the pipe. Check no water drips from the connection point before you go any further.

PD-03Fit an isolation valve if you don't have oneIf the cold feed under the sink has no valve, you'll need to add one. Cut the pipe cleanly with a pipe cutter, then fit a compression tee with a full-bore isolating valve so you can shut the dishwasher off on its own in future. Support the pipe while you cut it so you don't strain the rest of the run.

RULES

1 each · Compression tee, 15mm

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1 each · Isolating valve, 15mm

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1 each · Pipe cutter

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KNOW THE RULES

Any new pipework or fittings must comply with the Water Supply (Water Fittings) Regulations 1999 — use WRAS-approved fittings only.

PD-04Connect the water inlet hoseScrew the dishwasher's inlet hose onto the isolation valve. Tighten by hand, then give it a quarter turn with the spanner — don't overtighten, it only needs to be snug. If the hose washer looks worn or missing, fit a new one.

1 each · Rubber hose washer

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PD-05Connect the drain hoseMost sink traps have a pre-scored spigot for a dishwasher — knock it out with a screwdriver and push the drain hose on, securing it with the clip provided. If your trap has no spigot, fit a dishwasher waste connector onto the waste pipe instead. Keep the hose looped so the highest point is at least 400mm off the floor, or water can siphon back into the machine.

1 each · Dishwasher waste connector

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1 each · Hose clip

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PD-06Position and level the dishwasherSlide the dishwasher into its space, feeding the hoses and cable in behind it as you go. Check it's level side-to-side and front-to-back with a spirit level, adjusting the four feet with a spanner. Make sure no hose is kinked, trapped, or resting against a sharp edge.

1 each · Spirit level

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PD-07Connect the electricsPlug the dishwasher into a nearby 13A socket — most come with a fitted plug, so no wiring is needed. Choose a socket you can still reach easily once the dishwasher is in place, so you can unplug it in an emergency. If there's no socket nearby, don't run it off a permanent extension lead — get a qualified electrician to fit a proper one.

RULES

KNOW THE RULES

Plugging into an existing socket needs no notification. Adding a new socket or circuit from the consumer unit is notifiable work under Part P of the Building Regulations.

PD-08Turn the water back on and check for leaksOpen the isolation valve and turn the main stopcock back on. Check every new joint — at the valve, the inlet hose and the waste connector — with a dry cloth or kitchen roll, looking for drips. Watch them for a good 10 minutes; slow leaks often take a while to show.

1 each · Kitchen roll

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PD-09Run a test cycleRun a short cycle with the dishwasher empty. Watch the connections again while it fills and drains, and check the drain hose stays clear and doesn't kink. Open the door partway through to check the seal isn't letting water escape.

PD-10Tidy up and finishOnce you're happy there are no leaks, push the dishwasher fully into place. Flatten the cardboard box for recycling and wipe down the worktop and floor. Keep the instruction manual somewhere handy for future settings and error codes.

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