Pex Plumbing

[TheNescios]

Does anyone know if the topic of how to handle replacing the non-Pex flexible tubing been addressed previously?
If so, can someone point me in the right direction? My searching hasn't turned anything up.

After dealing with a leaking check valve nipple I started looking at the little bit of off-brand flexible tubing and don't like that there is Pex and off-brand tubing mixed together - seems like there should be a better solution.
Thank you!

[Cate&Rob]

Hi Chris,

Many on this forum have replaced all or some of the soft hose with Pex. A few years back, soft hose to Pex fitting leaks were very common. More recently, Grand Design is using flexible hose that is a better fit to the Pex fittings and leaks seem to be less of a problem. Use the forum search tool in the upper right corner. Scroll down to “Advanced Search”. Enter “replace soft hose” and perhaps “Cate&Rob” in the search criteria. This will find you lots of reading material on this topic.

Rob

[tlovell]

Hi Chris,

Many on this forum have replaced all or some of the soft hose with Pex. A few years back, soft hose to Pex fitting leaks were very common. More recently, Grand Design is using flexible hose that is a better fit to the Pex fittings and leaks seem to be less of a problem. Use the forum search tool in the upper right corner. Scroll down to “Advanced Search”. Enter “replace soft hose” and perhaps “Cate&Rob” in the search criteria. This will find you lots of reading material on this topic.

Rob

Possibly a silly question, but: What is the better flexible hose that you refer to. Our 2022 390 RK has flexible hosing that is color coded as per the pex coloring on the hose it attached to, in fact the colors are a perfect match. To my untrained plumbing eye, I would say that it appears to be of a reinforced flexible tubing with the nylon grid mesh imbedded in the layering. It appears to be correctly fitted with pex crimp fittings where used.

[Cate&Rob]

tlovell
Hi Tim and Terri,

Your 2022 Solitude may have a better fit braided hose . . . so this may or may not be an issue for you. For many years, Grand Design has used red and blue soft hose that is a loose fit on the Pex fittings and works loose, even though it is clamped with a Pex crimp ring. Braided hose is not designed to be crimped to these fittings . . . proper hose fittings have larger OD and much sharper barb rings. See attached picture of what can happen to a braided hose clamped to the too-small Pex fitting. In recent years, manufacturing has changed to a thinner wall smaller ID braided hose which is basically white with a colour tracer. This hose seems to fit the Pex fittings much better.

Rob

[acoleman43]

Hi Chris,

Many on this forum have replaced all or some of the soft hose with Pex. A few years back, soft hose to Pex fitting leaks were very common. More recently, Grand Design is using flexible hose that is a better fit to the Pex fittings and leaks seem to be less of a problem. Use the forum search tool in the upper right corner. Scroll down to “Advanced Search”. Enter “replace soft hose” and perhaps “Cate&Rob” in the search criteria. This will find you lots of reading material on this topic.

Rob

TheNescios I'm one of those that replaced most of my soft hoses due to many, many leaks. I didn't know GD were using better soft hoses now. That would have been nice.

[Cate&Rob]

TheNescios I'm one of those that replaced most of my soft hoses due to many, many leaks. I didn't know GD were using better soft hoses now. That would have been nice.

To be clear, I don't "know" that the soft hose currently being used by Grand Design is better than the red & blue hose used previously. On a recent factory visit, I happened to notice that the hose looked different and seemed to be a tighter fit to the Pex fittings before crimping. This is still a braided hose crimped to a Pex fitting . . . which only seems to be "approved" within the RVIA manufacturing requirements.

Rob

[acoleman43]

To be clear, I don't "know" that the soft hose currently being used by Grand Design is better than the red & blue hose used previously. On a recent factory visit, I happened to notice that the hose looked different and seemed to be a tighter fit to the Pex fittings before crimping. This is still a braided hose crimped to a Pex fitting . . . which only seems to be "approved" within the RVIA manufacturing requirements.

Rob

Thanks. The problem with those soft hose (in my opinion) is that once one fitting starts to leak, it dominoes. You fixe one fitting and the movement used to fix that fitting disrupts another fitting and it starts to leak. At some point you just replace all soft hose with real pex and have no more issues.

[tlovell]

tlovell
Hi Tim and Terri,

Your 2022 Solitude may have a better fit braided hose . . . so this may or may not be an issue for you. For many years, Grand Design has used red and blue soft hose that is a loose fit on the Pex fittings and works loose, even though it is clamped with a Pex crimp ring. Braided hose is not designed to be crimped to these fittings . . . proper hose fittings have larger OD and much sharper barb rings. See attached picture of what can happen to a braided hose clamped to the too-small Pex fitting. In recent years, manufacturing has changed to a thinner wall smaller ID braided hose which is basically white with a colour tracer. This hose seems to fit the Pex fittings much better.

Rob

Rob

Thanks for the explanation. I will invest in some water detector/alarms and hope for the best for now. I will let all know if anything untoward happens. Now I just have to fix the leaking fresh water overflow!

[Jlawles2]

This is making me want to go through the unit, and cut all of the soft lines, install PEX compatible valves, and then either properly MFG braided lines to the fixtures, or barb fitting on the valves for the braided hose.

[TedS]

You could also change to fittings with proper barbed ends for hose. I replaced the oem 80-psi hose to the pump outlet with a premade 150-psi hose from a pump silencing kit.

[Cate&Rob]

This is making me want to go through the unit, and cut all of the soft lines, install PEX compatible valves, and then either properly MFG braided lines to the fixtures, or barb fitting on the valves for the braided hose.

Hi Joseph,

In earlier builds, Grand Design tended to use all Pex or all soft hose on different lines. The idea of a soft hose pigtail on a Pex line came along later. Attached is a picture of most of the soft hose that I removed. I was lucky that the long runs to the kitchen island were already done in Pex . . . some have found these to be all soft hose. There are lots of choices of stainless braid flex hoses to go from Pex/copper plumbing to fixtures. Lowe's does a particularly good job of displaying these on a rack for comparison. It should be relatively easy to replace the fitting on the end of the Pex with one that adapts to a standard braided extension to the fixture. I went right to the fixtures with Pex on most of my rebuild and have not had any problems with this method.

Rob

[Guest]

Our 2017 Imagine has 150 psi rated braided hose and one did blow off its PEX fitting. Under the rig of course.

I noticed the PEX clamp looked like it had not clamped down on the hose enough since its one size fits all when the PEX tool is used to clamp it down. If the newer hose has increased wall thickness I could see it clamping better with a PEX clamp and fitting. A barbed fitting and a mini clamp in my case resulted in a tighter connection.



Jim

[TheNescios]

Information from this site has been helpful, and YouTube videos on PEX and other plumbing systems have helped - but the more I've read and researched, the more disappointed I am in the use of soft hose to PEX. Haven't found one bit of reliable information that supports this type of installation so am embarking on the fun of replacing the soft hoses after experiencing a run of leaks.
Who was the brain surgeon at Grand Design that come up with this idea? Guessing other brands do the same thing?

[Guest]

Personally I believe its the PEX clamp that is the issue on soft hose connected to a PEX fitting. The crimp tool will tighten to a specified limit based on the thickness of PEX tubing, not hose which is pliable. To convert to a barbed fitting and to use mini-clamps would be fine IMO. The hose in my Imagine is rated to 150 psi.

Jim

[StephenO]

Information from this site has been helpful, and YouTube videos on PEX and other plumbing systems have helped - but the more I've read and researched, the more disappointed I am in the use of soft hose to PEX. Haven't found one bit of reliable information that supports this type of installation so am embarking on the fun of replacing the soft hoses after experiencing a run of leaks.
Who was the brain surgeon at Grand Design that come up with this idea? Guessing other brands do the same thing?

Every other trailer I've seen uses the soft hose, so it's not just Grand Design who does this. The use of it is very likely related to the speed of installation, and it makes sense. A soft hose would be easier to route through small spaces and around corners and obstacles as compared to PEX. I'm aligned with Guest thought here that the real issue is the use of the smaller ID PEX fittings that don't have the correct barbs on them. Changing out to a proper barbed fitting should fix the issue, but replacing all of the piping with PEX would obviously be a good choice too, just more involved. As with everything, pros and cons to each option....