non return valve for dishwasher

[graham]

I want to put a non return valve into the waste pipe on a dishwasher.

I've been looking all over the net. I can find fitting kits for tapping into an existing sink pipe that include a non return valve. However, I can't find anywhere that just does an inline non return valve that can be spliced into the existing flexible waste discharge pipe on the dishwasher.

I have also tried a few local plumbing suppliers. It's the same thing. They all do the tapping kits, but not the inline valves.

Thanks, Graham

[Lobster]

Got one myself from B&Q, albeit many years ago; so they definitely do (did?) exist!

David

[Andrew Gabriel]

Some dishwashers have them built-in.

[Lee]

Got one from Wickes a while ago, but they do seem to be dropping some of the more useful bits :(

Lee

[OldBill]

I saw them in B&Q not long ago, grey plastic with both ends ridged. Looked as though they're supposed to go on the flexy-waste. Maybe they're called anti-siphon so thats why you can't find them?

[Andrew Gabriel]

Anti-siphon valve is different. It's an air admittance valve. It won't stop waste flowing backwards, it just stops it being siphoned back (or forwards) by allowing air into the pipe, like the exposed trap entry does.

[graham]

I asked in the local B&Q and they said they did not stock them. I can't find them on their web site.

A further web search didn't throw up an answer.

I shall keep looking.

Graham

[Pete C]

Hi,

Plenty on Ebay, one for a boat should be designed to cope with dirty bilge water and so be OK for a dishwasher.

This one looks like a plunger type instead of a flap type and so be less likely to get fouled:

What diameter hose do you need to connect to? I make the size of the tail on a plumbing out kit to be 20mm so the above item should be ideal.

cheers, Pete.

[Lobster]

OldBill's description actually fits the antisyphon valve equally as well as the non-return valve I was on about - mine had a built-in spring and plunger affair. I was in B&Q today buying plumbing bits (only cos BLOODY Lynx had lost my anticipated Screwfix order) and so had a shufti for it; couldn't see one I'm afraid.

David