Replacing polypropylene water lines with pex

Topic: Replacing polypropylene water lines with pex (Read 1235 times) previous topic - next topic

Replacing polypropylene water lines with pex

August 20, 2019, 08:15:51 am

My projected date for doing this is the summer of 2020. Any tips from those that have done this or have recommendations is appreciated. It appears to not be too complicated as there is easy access from the water heater thru the bathroom area, the drain valves, and kitchen covering a relatively short area. My concern is the area going to the shower and tub from the monoblock. Have any forum members replaced these grey polypropylene water lines to the shower and tub with pex?

My concern is how sanitizing our grey polybutelene pipes used in many older motorhomes, including my FT, build 5040 can and will speed up future leaks. These are caused by the sanitizer speeding up the hardening of the lines, leading to future water leaks. Not so much with pex. Up to now, I have only done short line line repairs utilizing pex and the following coupler.

SharkBite U4008LFA Conversion Coupling, 1/2-Inch by 1/2-Inch - Pipe Fittings...

Since sanitizing my polypropylene lines, which are more effected by sanitizer, than pex, I will be doing this project the summer of 2020. I recently purchased many feet of pex (following link) to replace as much of my lines as posible for a project the summer of 2020, this pex from Amazon, along with a few sections of straight line pex.

And so, have any forum members replaced these grey polypropylene water lines to the shower and tub with pex and how did it go?

Pexflow PXKT-RB10012 PEX Potable Water Tubing Combo Non-Barrier Pipe for...

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Re: Replacing polypropylene water lines with pex

Reply #1 – August 20, 2019, 10:29:08 am

Any guess as to what year Foretravel quit using polypropylene? My '81 has it and I had to carry a kit with lots of tee's, union's and fittings up in one of the storage pods to keep up with leaks on trips.
I don't see any grey lines in the'99.

Re: Replacing polypropylene water lines with pex

Reply #2 – August 20, 2019, 10:29:19 am

Jack, if you are going to replace all of the tubing with PEX invest in the tools to do the connections. With as many connections as you will make much cheaper than Shark Bite fittings.

Re: Replacing polypropylene water lines with pex

Reply #3 – August 20, 2019, 11:35:29 am

Our '93 model has had, to the best of my knowledge, zero water leaks in the original water pipes. I have never seen any sign of a repair, or come across a replaced section. (Except where I replaced our kitchen sink) Of course, the history of every coach is different. Our water system may not have been "sanitized" as often as yours. No way to tell...but I've never noticed any flora growing in the fresh water tank or the water lines.

Just saying...replacing pipes may not be something owners need to stress over, unless they start having leakage problems.

Re: Replacing polypropylene water lines with pex

Reply #4 – August 20, 2019, 11:51:23 am

Ditto what Roger said,get the Pex crimper,much better.

Re: Replacing polypropylene water lines with pex

Reply #5 – August 20, 2019, 01:38:21 pm

I think it must have been some time in the 97' year models that Foretravel started using PEX, because I am pretty sure I have seen pictures on the forum where OEM PEX was clearly visible in 97' model year coaches. That would mean that some 97's with a build date in 96' or even early 97' are using the polybutylene. It would be interesting to know what the build number cut off is for when the polybutylene was phased out.
Don

Re: Replacing polypropylene water lines with pex

Reply #6 – August 20, 2019, 01:57:03 pm

Quote from: Don & Tys – August 20, 2019, 01:38:21 pm

I think it must have been some time in the 97' year models that Foretravel started using PEX, because I am pretty sure I have seen pictures on the forum where OEM PEX was clearly visible in 97' model year coaches. That would mean that some 97's with a build date in 96' or even early 97' are using the polybutylene. It would be interesting to know what the build number cut off is for when the polybutylene was phased out.
Don

Poly in my 97, #5000.

Re: Replacing polypropylene water lines with pex

Reply #7 – August 20, 2019, 02:04:19 pm

Yours is 40 units earlier than Jack's, so that correlates with my theory... Now if someone with a 97' and PEX will chime in with their build date and number, we can narrow it down...
Don

Quote from: bdale – August 20, 2019, 01:57:03 pm

Poly in my 97, #5000.

Re: Replacing polypropylene water lines with pex

Reply #8 – August 20, 2019, 03:15:57 pm

I know #5161 is PEX and is an April '97 build.

Mike

Re: Replacing polypropylene water lines with pex

Reply #9 – August 20, 2019, 03:19:43 pm

Build 4810, have the grey lines.

Re: Replacing polypropylene water lines with pex

Reply #10 – August 20, 2019, 04:14:10 pm

Not trying to hijack this thread with a new topic but I think it adds to the discussion. If you are going to change to PEX, then what is your connection preference. PEX Crimp or PEX Clamp.

I feel I would go with the PEX Clamp. The video states that the PEX Clamp is easier to remove and the clamps are made from stainless steel. The crimp ring looks like they will rust and will be difficult to remove.
Just wondering,
John M.

Differences Between PEX Crimp Connections and PEX Clamp Connections - YouTube

Re: Replacing polypropylene water lines with pex

Reply #11 – August 20, 2019, 04:22:04 pm

John,
I have used both the crimps and punch clamps. They are both removable with the right tool. The crimps are made of copper, not steel. Removing the copper crimps requires cutting the pex shorter. I prefer the clamps for most applications.
Don

Re: Replacing polypropylene water lines with pex

Reply #12 – August 20, 2019, 04:24:59 pm

John,

I use nothing but the copper crimps.

@ Jack,
If you do go with crimps spend the money and buy a proper offset crimper. Well worth the $ over the ones you buy at a home improvement store. Look for one of these Zurn QCRT3CM (this should be for 1/2") they do make less expensive knock offs that seem to work just as good.

Mike

Re: Replacing polypropylene water lines with pex

Reply #13 – August 20, 2019, 05:05:37 pm

Quote from: Jack Lewis – August 20, 2019, 08:15:51 am

And so, have any forum members replaced these grey polypropylene water lines to the shower and tub with pex and how did it go?

Jack,

Getting to and removing some of the anti-viberation clamps so you can remove the old pipe is a big pain in the AZZ. Some places there isn't enough room to just leave the old and pull in new PEX.

Mike

Re: Replacing polypropylene water lines with pex

Reply #14 – August 20, 2019, 06:10:32 pm

I would recommend buying PEX in 50 foot rolls. Red and blue for color code.
You can save money and heart aches in buying sharkbite fittings in bulk pricing.
There are places you won't get the crimper tool in. Just my 2 cents.

Re: Replacing polypropylene water lines with pex

Reply #15 – August 20, 2019, 06:11:33 pm

If you have poly do you also have the manifold to turn each line on or off? I have the manifold and think I have pex but would not bet a beer on it at his time until I go and look.

Re: Replacing polypropylene water lines with pex

Reply #16 – August 20, 2019, 11:50:08 pm

I have used the crimp rings for years, but the tools that are needed to put them on are very large and difficult to get into any confined area, which is a distinct disadvantage in an RV.
The stainless clamps are easier to put on in confined areas and much easier to remove than the compression rings, even if you have the removal tool.
The Amazon tool for $24 with blue handles is much easier to work with and their supplies are way cheaper than Lowes or Home Depot.
On fittings you may want to consider the plastic rather than the brass connectors, the brass fittings are showing that they do deteriorate over time depending on water type etc.

Amazon: WGJW PEX Clamp Cinch Tool Crimping Tool Crimper for Stainless Steel Clamps

Re: Replacing polypropylene water lines with pex

Reply #17 – August 20, 2019, 11:54:22 pm

Typically the polypropylene Manablock is gray in color and the PEX Manablock is black

Re: Replacing polypropylene water lines with pex

Reply #18 – August 21, 2019, 10:25:51 pm

Like Chuck & Jeannie, our 93 has not had any leaks and it still has the original piping. ( I am almost hesitant to say that out loud, because you know what fate that tempts) Our units are essentially 'litter mates'. On a related matter we bought a house a few years back and when we were getting insurance for it one of the questions asked by the adjuster/underwriter was 'Does the house have grey PEX?'. I responded truthfully that it did did not have "grey PEX", it had "polybutylene piping". Note to self: even though we rented the house out it would be good to replace the 'poly B' with PEX, and I bought a 1/2" plus 3/4" crimper to do the job - both on the house and the 'not so tiny house on wheels'. now to get onto both of those projects. I think this comes under the heading of preventive maintenance.

Re: Replacing polypropylene water lines with pex

Reply #19 – August 22, 2019, 12:59:15 am

I replaced all of our galvanized pipes in our Mammoth Lakes house with PEX and used the crimps for all but one connection. The crimps work well, but required more space for the handle spacing. I found that if I had to remove a ring, I had to use my Dremel to cut and then a slot screwdriver to pry it off. Even then, it was nearly impossible to remove the tubing from the brass fitting. I ended up just cutting off the tube and throwing out the fitting, saving time. I was convinced that the connections would never leak or come apart on their own.
In the RV the clamp tool allowed me to get into tighter spaces since it acted more like a nibbler than a bolt cutter. I only used the push type fitting in one spot where space didn't allow for the tools. In really tight spaces, I found it easier to assemble a section while it was out in the open, then slide it in.
As mentioned previously, you can buy the tubing in coils or straight sticks. The coils were great when doing long runs and tracking around obstacles (vent pipes, etc), but I found that when I was making shorter connections I was constantly fighting the curves. I preferred using the straight sticks for most applications
When I bought the coach, PEX was a big selling point in selecting Foretravel. Wish I could use if for fuel lines. Good luck with the project.

Re: Replacing polypropylene water lines with pex

Reply #20 – August 22, 2019, 10:12:31 am

Build 5121...PEX

Re: Replacing polypropylene water lines with pex

Reply #21 – August 22, 2019, 10:29:26 am

5040, polybutelene .

Re: Replacing polypropylene water lines with pex

Reply #22 – August 22, 2019, 11:09:39 am

I have the grey polybutylene lines and have had only one leak and that was from contact with a sharp pointed screw. FT used lots of pointy screws in building the coach. I bought this crimp tool to make the repair and install a new sanitary compartment faucet and hose bibb. IWISS Combo Angle Head PEX Pipe Crimping Tool Kits Used for 1/2" & 3/4" Pex... You can get in rather tight places, although unless you have a really strong grip, you may need two hands for the crimping. The copper rings for pex are black. I will probably never use the tools again and I only used the 1/2" one and the cutter.

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Re: Replacing polypropylene water lines with pex

Reply #23 – August 29, 2019, 08:49:24 pm

My 1998 (built in 1997) is pex. I thought all FT were pex haha. I lucked out and have hub-centric wheels too.

Re: Replacing polypropylene water lines with pex

Reply #24 – August 29, 2019, 11:01:51 pm

Quote from: krush – August 29, 2019, 08:49:24 pm

I lucked out and have hub-centric wheels too.

You are lucky...my wheels are ego-centric. They think everything revolves around them.

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