# Why doesn't this plumbing fitting exist?

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#### Marc_G

##### Well-Known Member
This is just a mini rant in my "why is everything I do so much harder than it should be?" Series.

This Friday I'm getting a new fridge. Old fridge goes into the garage.

Anyway, the old fridge is over two decades old and has been a reliable workhorse. It will go to light duty to serve out its remaining time.

The ice maker in it is fed by my reverse osmosis water system that uses 3/8" OD PET tubing. There's a simple coupler valve using push connect fittings to connect the plastic tubing that is part of the fridge. Easy peasy.

The NEW fridge comes with a screw port for 1/4" compression fittings, and will arrive with a 6 foot stainless hose with the compression fittings (female) on both ends.

So I need to adapt my 3/8 feed line to 1/4" compression fittings, with a valve in there.

I would assume there should be exactly this piece for sale, as my situation of replacing old fridge is hardly unique.

Bit apparently they don't make a 3/8 push to 1/4 comp valve. I have to use three pieces: a valve with 3/8 push on both ends, then a short length of 3/8, then a 3/8 push to 1/4 MIP, then a 1/4 MIP to 1/4 compression adapter.

WTH? Why is this so complicated? And so many joints introduce lots of failure modes.

Am I missing something?

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#### OverTheTop

##### Well-Known Member
TRF Supporter
Bit apparently they don't make a 3/8 push to 1/4 comp valve. I have to use three pieces: a valve with 3/8 push on both ends, then a short length of 3/8, then a 3/8 push to 1/4 MIP, then a 1/4 MIP to 1/4 compression adapter.
WTH? Why is this so complicated? And so many joints introduce lots of failure modes.
That is the way a lot of times when you start mixing fittings, usually ending up with two or three parts to make the transition successfully. There are so many threads, including parallel and taper in the same thread pitch, as well as metric and various styles of swage and flare-type fittings.

Maybe there is a valve with threads that you can put a 1/4" threaded fitting in one side and a 3/8" sharkbite on the other, screwing into the valve. That would eliminate the short length of tubing and a couple of push fittings anyway.

Are those Sharkbite fittings reliable? I have never used them but the are available for plumbing here. I use the standard PEX barbed fittings as I have the tool for terminating the fittings. Just curious on the Sharkbite though.

#### Wayco

##### Desert Rat Rocketeer
I used a Sharkbite cap to seal off a leaky line I no longer needed. It was in a difficult place to get to, and several years later is still working. A bit pricey, but handy for tight spaces.

##### Well-Known Member
TRF Supporter
Yeah, fun adapting to things. I run into the same fun with adapting different things for maple syrup stuff since things are odd-ish sizes or are just different all over the place. Teflon pipe dope/tape are your friends

As for reliability of those push to connect fittings, my maple reverse osmosis runs at nearly 120 psi all spring. No problems over several years of that. Reminds me....need to get another membrane for this upcoming season to increase processing rate...

#### Funkworks

##### Low Earth Orbit, obstructing Earth's view of Venus
Well to answer the question literally, we'd have to know sales numbers. If they had the part, sales would probably be lower than for other parts. But by producing less of them, their cost to produce would greater (per part), so profit margins would be less.

#### neil_w

TRF Supporter
Custom 3D-printed fittings would be cool. The print material and method would need to be watertight and durable. Probably not FDM. Thinking of this as an easy-to-access service, not so much a DIY thing (although anyone with the appropriate printer at home could do it I suppose).

#### Marc_G

##### Well-Known Member
Now that I have solution #1 (multiple parts with several push connects) I'm considering a better solution: one push connect to compression adapter, followed by a short compression line, connected to a valve with compression on both ends. Might be another trip to Lowes for me. Benefit would be more reliable connections.

#### Jim Hinton

##### Well-Known Member
TRF Supporter
Try to stay away from metal fittings. RO product water is very pure, and as such, highly aggressive. Plastic fittings are the best choice, if you are in a situation where metal fittings are needed, try to stay to stainless. RO water will murder brass and bronze fittings. It causes 'de-zincification' and the fittings are rapidly reduced to a copper sponge.

Jim

#### Rob Campbell

##### Well-Known Member
It's a conspiracy by Big Plumbing to make you buy more fittings.

Flex-Seal

#### Marc_G

##### Well-Known Member
Unfortunately not. That one assumes push connect input for the fridge I think. The ice maker on my new one comes with a female compression fitting for 1/4" tubing, so I need to end at that. The hook up hose is this one:

It comes with fittings to go from 1/4 copper to the hose, which is a common scenario, but getting there from 3/8" PET is apparently a bit more exotic.

I'm not too freaked out since I have something that will work (a bit concerned about the one brass fitting though). If I get time I will get back to the hardware store before delivery.

#### Jim Hinton

##### Well-Known Member
TRF Supporter
Unfortunately not. That one assumes push connect input for the fridge I think. The ice maker on my new one comes with a female compression fitting for 1/4" tubing, so I need to end at that. The hook up hose is this one:

View attachment 487530

It comes with fittings to go from 1/4 copper to the hose, which is a common scenario, but getting there from 3/8" PET is apparently a bit more exotic.

I'm not too freaked out since I have something that will work (a bit concerned about the one brass fitting though). If I get time I will get back to the hardware store before delivery.
Hi Marc;
Stainless valves are stupid expensive. I found a few items on the MSC website that might help. Take a look and see what you think.
MSC #'s 45435757, 32151920, 85552834. None of them are a one piece solution, but we are getting closer. McMaster Carr has similar stainless and plastic valves and fittings as well. MSC shows a stainless 3/8" comp. x 1/4" NPT adapter with a built in valve. For the selling price you could have all of your ice delivered.

Jim

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#### 5x7

##### Well-Known Member
I just have to remark that this is the most on-topic thread ever for the Watering Hole.

#### Sandy H.

In my opinion, regardless of the solution, see if there is a good way to put a tray (or at least block off the perimeter of the fridge with a little curb) to trap water and put an audible water alert sensor in the tray.

Water can cause really annoying and expensive damage. I'm not the most social person, but I know 6 people who have had water damage from either in-wall plumbing (i.e. done by a professional when the house was built) or appliances like the fridge, dishwasher, garbage disposal etc. The cheapest fix was $5k, with much of the work being done by the homeowner (me. . . ) and the most expensive was around$50k (paid by insurance, as it was a hose-bib issue in a condo and the condo was required to maintain everything outside of the inside of the dwelling (whew for him!!!!)

Just a thought, as those little drips from multiple connections that weren't quite perfect add up over time. Even if your connections are perfect, the ones inside the appliance are made by the lowest bidder. . .

Sandy.

#### OverTheTop

##### Well-Known Member
TRF Supporter
I just have to remark that this is the most on-topic thread ever for the Watering Hole.
If you are worried about the tubing leaking or coming out you could always use some glue. What glue would you use?

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Call a plumber.

#### DES

##### Well-Known Member
Suggestion - this lash up will require less parts if you don't use the push fittings. Use a single 3/8 x 3/8 compression stop valve; then you can get a 3/8 x 1/4 reducer that threads directly onto one end of that. Two pieces, and only three joints.

#### sjh1

##### Well-Known Member
That is the way a lot of times when you start mixing fittings, usually ending up with two or three parts to make the transition successfully. There are so many threads, including parallel and taper in the same thread pitch, as well as metric and various styles of swage and flare-type fittings.

Maybe there is a valve with threads that you can put a 1/4" threaded fitting in one side and a 3/8" sharkbite on the other, screwing into the valve. That would eliminate the short length of tubing and a couple of push fittings anyway.

Are those Sharkbite fittings reliable? I have never used them but the are available for plumbing here. I use the standard PEX barbed fittings as I have the tool for terminating the fittings. Just curious on the Sharkbite though.
I have tried the sharkbite twice and failed both times.

#### Crazyrocket

##### Well-Known Member
You may want to look at SwageLok. The have a multitude of different valves with connections using compression and push fittings. We use the push fittings for compressed at lines and they can hold our line pressure which is typically 100 psi. They come in SS. Might be a bit pricey though.

#### kuririn

##### BARGeezer
TRF Supporter
Suggestion - this lash up will require less parts if you don't use the push fittings. Use a single 3/8 x 3/8 compression stop valve; then you can get a 3/8 x 1/4 reducer that threads directly onto one end of that. Two pieces, and only three joints.
Marc will still need something to connect the pex tubing to the 3/8" valve.

#### Marc_G

##### Well-Known Member
I went back to Lowes today, and came away empty handed. I looked for and didn't find the 3/8 OD to 1/4" MIP that would have let me reduce the number of junctions. Maybe they were out of them.

After Lowe's I went to a real plumbing store, but they too didn't have a solution, oddly. They agreed with me that the brass fitting, over time measured in years, will fail. Somehow I seem to raise questions that most people don't bother with.

I've emailed my plumber, a good guy who installed my tankless water heater (new exhaust, gas line, and water piping) as well as moved a gas line for my new oven project. I don't expect a quick response but I'm sure he will get back to me eventually.

I just don't get why this takes effort at all. This is about the most common application out there in the "replacing old fridge" space.

I'm beginning to think that this will eventually go a different way: the fridge has a male 1/4" compression fitting; so that's non-negotiable. I could get a longer stainless steel supply line, say 20" ($11 on Amazon), and feed it under the floor, moving the "point of eventual failure" away from my main floor kitchen wood floors and instead over concrete basement floor with a floor drain going to the sump. Meanwhile, the sharkbite.com website sucks; I can't even find the products I already bought there (and their search feature sucks). I thought I could find the bits I bought, then search around to see if they had one in that same line that had the right ends. No luck. Grrr. #### Marc_G ##### Well-Known Member OK, so ideally you are looking for a stop valve with 1/4' threads for a compression fitting on one side and 3/8" push to fit fitting on the other side, right? This is not a valve but it will connect your 1/4" braided hose to the 3/8" pex line. Then you can splice in a stop valve in the pex line further down. U276LF - SharkBite U276LF - 1/4" Sharkbite x 3/8" MIP Reducing Dishwasher 90° Elbow Lead Free (supplyhouse.com) Thanks for this, but being brass it will degrade over time and leak. I'm still seeking my unicorn of a non-brass solution. #### Jim Hinton ##### Well-Known Member TRF Supporter I went back to Lowes today, and came away empty handed. I looked for and didn't find the 3/8 OD to 1/4" MIP that would have let me reduce the number of junctions. Maybe they were out of them. After Lowe's I went to a real plumbing store, but they too didn't have a solution, oddly. They agreed with me that the brass fitting, over time measured in years, will fail. Somehow I seem to raise questions that most people don't bother with. I've emailed my plumber, a good guy who installed my tankless water heater (new exhaust, gas line, and water piping) as well as moved a gas line for my new oven project. I don't expect a quick response but I'm sure he will get back to me eventually. I just don't get why this takes effort at all. This is about the most common application out there in the "replacing old fridge" space. I'm beginning to think that this will eventually go a different way: the fridge has a male 1/4" compression fitting; so that's non-negotiable. I could get a longer stainless steel supply line, say 20" ($11 on Amazon), and feed it under the floor, moving the "point of eventual failure" away from my main floor kitchen wood floors and instead over concrete basement floor with a floor drain going to the sump.

Meanwhile, the sharkbite.com website sucks; I can't even find the products I already bought there (and their search feature sucks). I thought I could find the bits I bought, then search around to see if they had one in that same line that had the right ends. No luck. Grrr.
What is the water like without RO? I'm guessing ugly. Is the RO purely to supply the fridge? Do you have any other in-house treatment? Lifespan on brass/bronze in that environment will be hard to predict. There is a known issue with corrosion but we don't know how fast or slow it will go. To use RO water and minimize failure points I would consider using plain 3/8" PEX or PE as a feed line with push fittings on the ends. Preferably plastic. Those are available for a reasonable price through MSC. For what it's worth, I used to do this kind of work a lot. You will usually have to order fittings through a specialty house if you want to do it right and I can tell you do.

Jim

#### Marc_G

##### Well-Known Member
What is the water like without RO? I'm guessing ugly. Is the RO purely to supply the fridge? Do you have any other in-house treatment? Lifespan on brass/bronze in that environment will be hard to predict. There is a known issue with corrosion but we don't know how fast or slow it will go. To use RO water and minimize failure points I would consider using plain 3/8" PEX or PE as a feed line with push fittings on the ends. Preferably plastic. Those are available for a reasonable price through MSC. For what it's worth, I used to do this kind of work a lot. You will usually have to order fittings through a specialty house if you want to do it right and I can tell you do.

Jim
Thanks Jim,

The water supply to the house is hard alkaline well water. It goes through a salt based softener on the way to the sink. Under the sink is a membrane based RO system (a good, well maintained 5 stage system), that supplies a small faucet at the sink and the ice maker.

Ice made from tap water sucks here. No go.

I don't know why the fridges now require these compression fittings. Seemed to work just fine when the fridge arrived with a coil of PE tubing in the back and you pushed it into a coupler and called it done.

#### kuririn

##### BARGeezer
TRF Supporter
One more alternative.
Let's try steel.
Get a Sharkbite 3/4 X 3/4 X 1/4 COMP stop valve.

Get an EvoPEX end cap

Cut a short length of pex tubing and push the end stop to the tubing, then push the tubing onto the valve. Discard the compression nut and sleeve that came with the new valve and connect your 1/4" compression fitting and 3/8" push to fit tubing to the valve. Done..

#### Marc_G

##### Well-Known Member
One more alternative.
Let's try steel.
Get a Sharkbite 3/4 X 3/4 X 1/4 COMP stop valve.
View attachment 487668

Get an EvoPEX end cap

View attachment 487670

Cut a short length of pex tubing and push the end stop to the tubing, then push the tubing onto the valve. Discard the compression nut and sleeve that came with the new valve and connect your 1/4" compression fitting and 3/8" push to fit tubing to the valve. Done..
We might have a winner here... Thank you.

#### Marc_G

##### Well-Known Member
Oops the one @kuririn mentioned has 3/4 ends not 3/8. I will have to check to see if they have similar with 3/8.