Plumbing in dishwasher

[ladwey]

I'm installing an Ikea dishwasher and I'm having a hell of a time with the input hose. They said it's a 3/4in connection, so I put a 22mm reducing coupler on my 15mm pipe. But the plastic connector barely fits on it, it's very difficuot to twist on, and I worry if I try too hard to get it on I'm going to damage the thread which would cause no end of trouble. Does anyone have any tips? Should I just force it?-- surely not!

 

[ladwey]

Is this what I need? -- https://www.amazon.co.uk/gp/aw/d/B08HLZ392Q?ref=ppx_pt2_mob_b_prod_image

I had been told that 3/4in and 22mm were interchangeable.

 

[Rodders53]

You need an appliance isolating valve... But a decent brand rather than random **** off Amazon/ebay.

Pegler from Toolstation or Screwfix. Straight or 90 degree angled. Goes onto 15mm pipes usually.
May be called washing machine valves. The mating surface is flat so the rubber washer in the plastic connector seals.

3/4 BSP thread is not the same as 22mm compression fittings' thread afaik... nor are the two pipes the same equivalent dimensions.

 

[Deleted member 267285]

Is this what I need? -- https://www.amazon.co.uk/gp/aw/d/B08HLZ392Q?ref=ppx_pt2_mob_b_prod_image

Yes, it’s similar or a tee, Depending on your setup. As above though, get a decent brand.

I had been told that 3/4in and 22mm were interchangeable.

threads aren’t.

 

[ladwey]

Thanks for the useful replies -- screwfix has just the thing, I'll pop there in the morning.

 

[Madrab]

I had been told that 3/4in and 22mm were interchangeable.

Go back and tell them they're wrong - as far as pipe sizes/fittings are concerned - 1/2" and 15mm are interchangeable - 22mm and 3/4" are not.

3/4" BSP threads (that the washing machine hose uses) have no relation to pipe size and have no real metric fitting alternative.