Installing dishwasher - Compression Tee fittings?

[Jamieb]

Hey,
Rookie here trying to install my dishwasher at home,
From what i can see i need a compression fitting tee,
1/2" M to connect to the wall, 1/2" F to connect to the existing pipe and 3/4" M to connect to my dishwasher line.
From what i can see they would call this a
15c 20c 15Fi fitting
But i cannot find a fitting like this in existence?

 

[justin_dewan90]

Are you sure that's what the measurements are?

 

[justin_dewan90]

Sure it's not 3/8?

 

[havasu]

They have recently changed the normal dishwasher connections. I got so frustrated with the last one I installed that I ended up just buying a stainless steel flexible hose which had the necessary fittings, which tied into my 3/8" fittings on the angle stop

 

[Jamieb]

I am 99% it is 1/2"
I had it dodgeyd in at my old house which had the same connections, using a polly fitting which has on it "' 1/2'' 15mm '" (in my world 1/2'is 13mm?)

 

[justin_dewan90]

I believed you on the 1/2, just not on the 3/4. But Havasu says they changed something with new dishwashers. Haven't put one in in about a year or so. So not savvy to what they are like if they've changed.

 

[Jamieb]

I just measured the OD of the threads and they are approx 20mm and 25mm ..
Seems this is what i need https://www.ebay.com.au/itm/Plumb-P...783308923?epid=1105019608&hash=item283ab0107b

It seems odd that they measure 1 end in metric and the other imperial? and that 15mm is called 1/2"

 

[Matt30]

Post pictures of what you’re trying to do

 

[justin_dewan90]

Wasn't trying to be confusing. I do know this. I'll reiterate, I was questioning the 3/4 part. Didn't know dishwashers came with 3/4 connections. That's all.

 

[justin_dewan90]

Sorry, read your post wrong. Disregard my previous post.

 

[justin_dewan90]

And I'll eat my words. I thought 12mil is 1/2? Kind of odd it'd be 15mil. Might just look and see if there is a brass adapter to transfer from the dishwasher water line to a regular shut off.

 

[Jamieb]

Yeah im a mechanic and we call 1/2"13mm but on one of the polly fittings i used last time is says (1/2"- 15mm) But i know in the world of pipes and fittings things are measured in different ways..
The dishwasher hose is the same as you would find on a washing machine,
THIS is what i need, i may just have to order off the net and wait 4 weeks..

 

[justin_dewan90]

Yeah but I thought that was for just under the dishwasher and then it converted at the other end? Learning something new. You should be able to go to a supply house or a good hardware store and findl exactly what you need without waiting.

 

[jwwing]

Pipe size is 1/2" - 13 mm - but the fitting is 15 mm or 9/16"

The normal shutoff in the States is 3/8" and is not compression fittings unless you want them to be. The hardware stores sell these neat little connectors that adapt from the machine to the shut off. So if it uses a 3/8" tube, it will have a 1/2" or 9/16" nut or perhaps even larger to make it possible to hand tighten.

I am sure that there is a name for this type of connector, but it is not a 'compression fitting although it uses compression by the outer cap to conform the bulbous tip onto the shutoff which has a shape to accept the tube end. A compression fitting generally has a ring of material that is collapsed or compressed onto another material to effect the seal between the two and the ring then also seals to the output of the shut off. The material of the ring is usually copper or plastic. I doubt that you have one of those. They are usually more expensive and less common.

I looked at the description that you posted and you appear to be correct. These are definitely not what we normally run into. It appears that a compression fitting is being used to connect between the line coming in and the feed to the dish washer - in fact if I read that correctly, it looks like an ordinary garden hose connector for the dish washer.

But are you sure that you have to cut the line? The only way to T in is to cut the line to install this connector - is that what you are proposing needs to be done? Seems a bit like overkill. Usually there is some kind of fitting where a threaded T could be installed so that two shutoffs one for whatever the run was for and one for this unit. Otherwise, I would suggest that you install a T of the normal variety such as a copper sweat fitting if that is what is there, and not use the compression valve, just install a normal shutoff onto a regular T like your system uses. (If plastic use plastic, if copper use copper, etc., install the plumbed T and then install the shutoff.) I would avoid the compression fittings - but that is just me.

 

[Geofd]

I install dishwasher on almost a daily basis some older connections are 1/2 od compression and most now are 3/8 compression there are kits out there that convert the compression size between 1/2 ips...1/2inch compression or 3/8 ips… to 3/8 compression

 

[Jamieb]

OK so here is what i had hooked up before i moved.. It done the job but did leak a little which i am assuming is coming from the Polly fitting..
I need a tee with a female compression fitting instead of the polly adaptor, or a correct adaptor to join 2 male compression fittings together..

 

[frodo]

if you wish to do it correctly
you need to remove the valve at the wall
it is most likely this. 1/2 x 3/8 angle stop

and need to replace it with this 1/2 x 3/8 x 3/8 double angle stop

and you need this under your dishwasher 1/2'' mip x 3/8'' compression 90

 

[Jamieb]

there is currently no valve at the wall, it is just 1/2"coming out of the wall going to the tap.
there is no 3/8" fittings in the plumbing- , my tap is 1/2" and my dishwasher is 3/4" ..

 

[frodo]

there is currently no valve at the wall, it is just 1/2"coming out of the wall going to the tap.
there is no 3/8" fittings in the plumbing- , my tap is 1/2" and my dishwasher is 3/4" ..

is this what you are looking at under the dishwasher? are the 3/4'' threads a hose fitting thread?
if you do not have a valve at the wall, you really need one