Soft Hose Fitting Leaks

[Cate&Rob]

GDRV uses two types of water pipe/hose (Pex and a softer hose) but only one type of fittings (Pex - usually plastic). Several of us have encountered leaks from the soft hose to Pex fitting combination. There is a reason for this. The soft hose has too large an ID to stay sealed to a Pex fitting. With vibration and temperature cycling these connections will work loose.

This came up at the Elkhart Rally Kantleak Tech Session, but I was recently asked by another forum member about how to best solve this. At first, I though maybe a Sharkbite fitting would work, but as has been mentioned previously on this forum, Sharkbite fittings are not designed to work with soft hose.

The soft hose has a 1/2" ID and barbed hose fittings are available in 1/2" OD. Once you realize that you are working with hose, not pipe, the solution becomes straight forward . . . but rather a PITA to have to do. If the proper fittings had been used in the first place, we wouldn't be doing this.

Proper fittings are available at Home Depot or similar. Pictures and comments on what should go with what are in the attached.

Rob

 

[Second Chance]

Great write-up, Rob. Must be starting to get a little cooler up there, eh?

Other Rob

 

[Cate&Rob]

Great write-up, Rob. Must be starting to get a little cooler up there, eh?

Other Rob

Thanks "other Rob" - it has actually been an amazingly warm Fall for us. Haven't even hit freezing yet! . . . which is unusual. I was out in shorts waxing the RV, just a few days ago. We head for Florida in 3 weeks !!

Rob

 

[Cate&Rob]

A specific example of fixing one of these soft hose to Pex fitting leaks . . .
Found one on the backside of my Kantleak panel (surprise surprise ) so I took a couple of pics of the fix.
Made an adapter with a proper size barbed fitting for the soft hose side and a short piece of Pex for the other side.
(I have nor been able to find a barbed hose to compression nut fitting)
We should not have to be doing this . . . but it is not difficult to accomplish.

Rob

 

[webpilot]

Rob,

You are confusing me. As I understand this, you had a drip leak from the PEX connection to the 90* fitting. So to fix it, you added a piece of soft hose to the mix? It appears that you have the same PEX to 90* fitting that you had dripping originally? How is that going to stop the leak? What am I missing here?

 

[Cate&Rob]

Rob,

You are confusing me. As I understand this, you had a drip leak from the PEX connection to the 90* fitting. So to fix it, you added a piece of soft hose to the mix? It appears that you have the same PEX to 90* fitting that you had dripping originally? How is that going to stop the leak? What am I missing here?

Hi George,

The combination that leaked (top of the picture) is soft hose -> Pex 90* fitting. (The soft hoses have the darker writing on them).
See the attachment to post #1 of this thread for the dimensions of why this does not work for long.
So . . . I had to get Pex on to the original 90* and then adapt to the correct fitting and hose clamp for the soft hose.

Rob

 

[TucsonJim]

Rob - Without closer examination, the "softer" hose appears to be PE-RT (Polyethylene - Raised Temperature) tubing. It is very common in European potable water systems. It is typically more flexible and less expensive than PEX. It can also handle higher temperatures for prolonged periods. The downside is that it is also softer. If it is indeed PE-RT tubing, standard PEX clamps are a poor choice for terminating the connections. There are PE-RT specific fittings available. Interestingly enough, many Shark Bite type fittings are also satisfactory with PE-RT.

Jim

 

[webpilot]

Hi George,

The combination that leaked (top of the picture) is soft hose -> Pex 90* fitting. (The soft hoses have the darker writing on them).
See the attachment to post #1 of this thread for the dimensions of why this does not work for long.
So . . . I had to get Pex on to the original 90* and then adapt to the correct fitting and hose clamp for the soft hose.

Rob

Thanks Rob, I thought the original was a PEX line. Sorry for the confusion!

Thanks for the explanation and your fix! I have been lucky enough to not have any KanLeak issues so far, but I figure it is just a matter of time. The problems will have to wait a while now to show up as the 337 is in storage until sometime next year.

My best to you and your family!

George

 

[Cate&Rob]

Hi Jim,

I have tried to cross reference the markings on this hose and not found anything useful. I do not think it is anything nearly as sophisticated as PE-RT (http://msdssearch.dow.com/Published...ipes/pdfs/noreg/003-08801.pdf&fromPage=GetDoc) It has a braid in it and in cross section looks very much like the common white potable RV water hose. I have tried to get it into a Shark Bite and its a lot of work because the OD is larger than copper/Pex/rigid plastic alternatives. The big problem is that it has too large an ID to be a proper fit to a Pex fitting. Once you insert a proper 1/2" barbed hose fitting, the OD becomes too large for a standard Pex clamp . . . thus the worm gear clamp which seems to work just fine (since this is a hose rather than pipe or tube).

Rob

 

[JCR GD]

I got lucky and just adding a hose clamp to the existing connection stopped the leak.

 

[Biery-Bullock]

Thanks Rob for the great PDF explaining the problem. In an attempt to avoid performing major surgery I... 1) replaced the plastic fittings with brass ones on the bathroom and kitchen hot and cold lines and 2) used heat-shrinkable tubing to increase the diameter to ~0.5". So far it's holding with no leaks. Fingers crossed...

 

[ThePowells]

Thanks Rob for the great PDF explaining the problem. In an attempt to avoid performing major surgery I... 1) replaced the plastic fittings with brass ones on the bathroom and kitchen hot and cold lines and 2) used heat-shrinkable tubing to increase the diameter to ~0.5". So far it's holding with no leaks. Fingers crossed...

I opted to go for major surgery. https://www.mygrandrv.com/forum/sho...s-adventure-into-plumbing-AKA-What-soft-hoses I have two minor leaks to address now. One is the new connection on the kitchen hoses and the other is a connection for the black tank flush line.

 

[Biery-Bullock]

Ouch! Major surgery indeed, Jerry. If we keep having problems I may need to do the same some day. Good luck with the remainder of your project.

 

[chrisopy]

GDRV uses two types of water pipe/hose (Pex and a softer hose) but only one type of fittings (Pex - usually plastic). Several of us have encountered leaks from the soft hose to Pex fitting combination. There is a reason for this. The soft hose has too large an ID to stay sealed to a Pex fitting. With vibration and temperature cycling these connections will work loose.

This came up at the Elkhart Rally Kantleak Tech Session, but I was recently asked by another forum member about how to best solve this. At first, I though maybe a Sharkbite fitting would work, but as has been mentioned previously on this forum, Sharkbite fittings are not designed to work with soft hose.

The soft hose has a 1/2" ID and barbed hose fittings are available in 1/2" OD. Once you realize that you are working with hose, not pipe, the solution becomes straight forward . . . but rather a PITA to have to do. If the proper fittings had been used in the first place, we wouldn't be doing this.

Proper fittings are available at Home Depot or similar. Pictures and comments on what should go with what are in the attached.

Rob

Hi Rob,

Wasn't sure to start a new thread or reply to this one. Anyways, my leak is on my hot line under kitchen sink where the arrow is between the bottom of the black fitting and top of the soft hose. My hose looks a little different than your pic, but still is soft. Do you think the brass barbed fitting and hose clamp will be the best route in my situation too, or any other suggestions. I can't replace the whole line since it goes under the kitchen island on our MK2670. If I ever do want to adapt this hose to pex lines, what fittings do you recommend? Thanks in advance and great write up.

 

[Cate&Rob]

[MENTION=29860]chrisopy[/MENTION]

You are picking up an a very old thread . . . but that is OK .
Look very carefully at the area where the water is leaking. Is it coming from the hose on the left or the black collar on the right?

If it is from the hose, this is where you will need to make an "adapter" from Pex pipe to the correct barbed fitting for hose as described earlier.

If the drip is coming from the black collar on the right, this is a different (easier to fix) problem. The reason that I wonder about this is that there is teflon tape on the the threads of that fitting . . . which is not the way to solve a leak with this type of connection. Inside that black plastic part is a "cone washer" that seals against the end of the brass part with the thread tape on it. These cone washers are difficult to source by themselves, but you can buy a similar fitting at any plumbing store and just use the new cone washer on your existing fitting. In the attached picture the internal fitting is brass and the collar is white, but the black rubber cone washer will also fit your existing fitting.

Rob

 

[chrisopy]

[MENTION=29860]chrisopy[/MENTION]

You are picking up an a very old thread . . . but that is OK .
Look very carefully at the area where the water is leaking. Is it coming from the hose on the left or the black collar on the right?

If it is from the hose, this is where you will need to make an "adapter" from Pex pipe to the correct barbed fitting for hose as described earlier.

If the drip is coming from the black collar on the right, this is a different (easier to fix) problem. The reason that I wonder about this is that there is teflon tape on the the threads of that fitting . . . which is not the way to solve a leak with this type of connection. Inside that black plastic part is a "cone washer" that seals against the end of the brass part with the thread tape on it. These cone washers are difficult to source by themselves, but you can buy a similar fitting at any plumbing store and just use the new cone washer on your existing fitting. In the attached picture the internal fitting is brass and the collar is white, but the black rubber cone washer will also fit your existing fitting.

Rob

It's such a small leak and infrequent, but I believe it's coming from just under the black collar itself. It leaked before I added the teflon tape also. I just added the tape to see if it would do anything. In the picture you have attached in your reply could I just use that type of fitting since it comes with a new cone washer and barbed fitting anyways? Basically get rid of the crimp ring and use this fitting with a hose clamp to replace what is one there now. I see it has a barbed fitting and should work on the soft hose like the original directions in the post.


On a side note, do you see my reply whether I reply with quote or I would use [MENTION=888]Cate&Rob[/MENTION] like you did to me? Is there a difference?
Thanks!

 

[Biery-Bullock]

Chiming in here... I used the same brass fitting and increased the diameter with heat-shrinkable tubing for a tighter fit in the soft hose. My attempt at using an ordinary (screw-tightened) hose clamp failed, however, so I invested in a Pex crimping tool that came with a supply of Pex fittings (available on eBay for ~$25). Good luck.

 

[Cate&Rob]

[MENTION=29860]chrisopy[/MENTION],

The brass fitting in the picture is a Pex fitting. The “barbs” that you see are sized for Pex tubing and are too small for the soft hose . . . which is the problem in the first place. If the leak is coming from under the black plastic fitting, replace just the rubber cone washer and you will likely solve the problem.

As to how to communicate through this forum . . . I used to be a lot more involved than I am now. I used to receive email notification of questions, but this seems to have gone away. Send me a PM (private message) if I don’t see your questions.

Rob

 

[chrisopy]

Chiming in here... I used the same brass fitting and increased the diameter with heat-shrinkable tubing for a tighter fit in the soft hose. My attempt at using an ordinary (screw-tightened) hose clamp failed, however, so I invested in a Pex crimping tool that came with a supply of Pex fittings (available on eBay for ~$25). Good luck.

Thanks for the suggestion.

 

[ThePowells]

[MENTION=29860]chrisopy[/MENTION] , Something that you can try is using a Pex connector, hook a Pex line to the soft line and then with some help try feeding it through and see if you can replace it that way. If it isn't making any hard turns, then you just might slay the dragon that way.