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Title: Pex plumbing lines? Size does matter!
Post by: grantgoold on August 22, 2008, 04:30:50 PM
Trying to get some idea of the size of the water lines for my bus. I plan on using PEX.

What size have you used?

Thanks

Grant


Title: Re: Pex plumbing lines? Size does matter!
Post by: FloridaCliff on August 22, 2008, 06:24:30 PM
3/4" trunk line

1/2" to fixture

In the short run of a bus, should be just fine, as a matter of FACT, it does work just fine.....

Cliff


Title: Re: Pex plumbing lines? Size does matter!
Post by: grantgoold on August 22, 2008, 06:28:57 PM
Is 3/8 too small? I have folks that have an entire lot of PEX line and connections they want to give away but I do not want to put something into the system that is too small.

Thanks

Grant


Title: Re: Pex plumbing lines? Size does matter!
Post by: FloridaCliff on August 22, 2008, 06:34:09 PM
Is 3/8 too small? I have folks that have an entire lot of PEX line and connections they want to give away but I do not want to put something into the system that is too small.

Thanks

Grant

Grant,

I would use the 3/8 as the feed to the fixture without worry, but I would still run a 3/4 trunk for the volume....

Cliff


Title: Re: Pex plumbing lines? Size does matter!
Post by: Dallas on August 22, 2008, 06:34:53 PM
Grant,
PEX is 1/2"OD ans 3/8" ID. I've been using 1/2" for the last 8 or 9 years with no problems except a FUBAR activating switch.

Shurflo has a download to figure out what you need to set your system up.

http://www.shurflo.com/pdf/rv/911_trouble_shooting/new/911-352-I.pdf


Title: Re: Pex plumbing lines? Size does matter!
Post by: FloridaCliff on August 22, 2008, 06:43:31 PM
Grant,

On using the 3/4.....

Have you ever heard anyone complain about too much volume of water...... ::)

Next............. ;)

Cliff



Title: Re: Pex plumbing lines? Size does matter!
Post by: TomCat on August 22, 2008, 07:07:14 PM
Grant,

On using the 3/4.....

Have you ever heard anyone complain about too much volume of water...... ::)

Cliff


Yeah! When something breaks!

Jay
87 SaftLiner


Title: Re: Pex plumbing lines? Size does matter!
Post by: kyle4501 on August 22, 2008, 07:51:34 PM
Since I'm the one dumping the holding tanks  :-[ . . . .
Since I don't have any hair to wash  :o . . . . .
Since water = weight & weight = more fuel  :'( . . . .
Since the less water you use, the longer a 6 gallon hot shower lasts  ;D . . . .


I'm gonna use 3/8 . . . . unless 1/2 is cheaper   :o

My airstream is plummed with 3/8. The shower has lower flow than the house, but still enough for a great shower - long hair takes longer (but I don't have to wash my back every time  :o )


Besides, if someone doesn't like the shower in the camper, they can use the campground facilities.  ;)


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 22, 2008, 08:45:46 PM
 Grant,what would be the propose of using a tubing size larger than the pumps inlet and outlet I have the 5.7 smart sensor pumps and they have 1/2in inlet and outlet and work on about 60# of pressure.Mycoach is all 1/2 in  good luck


Title: Re: Pex plumbing lines? Size does matter!
Post by: Tony LEE on August 23, 2008, 06:22:48 AM
if you do mostly boondocking then the smaller the diameter the less water you waste waiting for the hot water to arrive. Ways around it of course but running small hot and cold pipes from a central manifold to the individual points results in much less pressure fluctuations - especially in the shower - when someone turns a tap on elsewhere


Title: Re: Pex plumbing lines? Size does matter!
Post by: makemineatwostroke on August 23, 2008, 06:50:26 AM
I would follow your pump manufacturers guide lines these pumps are going to pump just so much water period the larger the pipe the less pressure you are going to have after the initial start.I have never owned a RV mostly Blue Birds with larger than 1/2 inch tubing with 2 pumps,besides 1 size tubing is easier to carry parts for than 3 sizes


Title: Re: Pex plumbing lines? Size does matter!
Post by: Damn Yankee on August 23, 2008, 06:52:19 AM
I used 1/2 throughout my system and it works just fine. Also used sharkbite connectors (http://www.sharkbiteplumbing.com/?gclid=COyihLmKpJUCFQkmIgodS2hfbQ) for the t's & 90's. had my fresh water system together and working in less than 2 hours with no leaks!


Title: Re: Pex plumbing lines? Size does matter!
Post by: Nick Badame Refrig/ACC on August 23, 2008, 07:48:35 AM
Hi Guy's,

Cliff has stated the proper way to do so.

Weather or not 1/2", 3/8", or 3/4 pex works for you for a manifold before branch runs, is your personal choice.

I plumbed my system the proper way for 2 reasons, water volumme and resale value!

If thats not important to you, then do it your way. It will still work!

Good Luck
Nick-

 


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 23, 2008, 08:38:35 AM
Grant, fwiw the flow rate on 1/2 in pipe is 5 gpm on 3/4 in it is 12 pm but the flow rate is as good as your 2.8 gpm or 5.7 gpm pump you are not going to get 12 gpm with a RV pump no matter what size pipe you use according to the Boyles and Charles law for water distribution. It looks to me that  the 5.7 smart sensor pump would be ideal for a 1/2 pipe with just a small amount left over


Title: Re: Pex plumbing lines? Size does matter!
Post by: belfert on August 23, 2008, 08:45:28 AM
I have a manifold with 3/4" inlets and 1/2" PEX outlets.  The 3/4" inlets don't help much as my tank outlets are only 1/2".


Title: Re: Pex plumbing lines? Size does matter!
Post by: Tom Y on August 23, 2008, 09:22:52 AM
Grant, If you run 3/8 to the shower you should be able to pull the controls out if the tubing is long enough. If 1/2 or bigger better have access to the back.  Tom Y


Title: Re: Pex plumbing lines? Size does matter!
Post by: Sam 4106 on August 23, 2008, 09:40:05 AM
Hi Grant,
Have you ever taken a faucet apart? If you have, you know that the ports are no larger than 1/4". Use the 3/8" lines, you will have all the water you need. And, at a very reasonable price.

How often do any of you use more than one faucet at a time? We almost never do.

Good luck, Sam 4106


Title: Re: Pex plumbing lines? Size does matter!
Post by: grantgoold on August 23, 2008, 11:05:26 AM
I have the opportunity to purchase 500 ft of pex 1/2 od, 3/8 id (250ft in red and 250ft in blue) for $50. I was hoping that once I am done someone else on the board can use what I have left?

Thanks for all the help.

Grant


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 23, 2008, 11:07:43 AM
Grant, one way to figure it is the new faucets and shower heads  use very little water the bathroom use more water than any place a new shower head will use 1.5 gpm the new faucets use 3.5  pm you can add aerators to them and bring that down to a 1/2 gpm so with a kitchen and bathroom faucet with aerators that is 1 gpm add the 1.5 gpm for the shower and you are talking about 2.5 gpm and with the right pump you could even flush the toilet while using everthing. My water system was a over kill and I am planing to change over to all the low water use items that way gray water will not be a problem anymore for me use the $50 stuff sounds good to me.I have the criping tool and cutters you can use if you will return  them to me


Title: Re: Pex plumbing lines? Size does matter!
Post by: JackConrad on August 23, 2008, 11:15:55 AM
I have the opportunity to purchase 500 ft of pex 1/2 od, 3/8 id (250ft in red and 250ft in blue) for $50. I was hoping that once I am done someone else on the board can use what I have left?
Thanks for all the help.
Grant

Grant,
    A couple tips. First, buy a pair of the pex/CPVC cutters.  The are kinda like a ratcheting piers looking thing and available at any home supply store. It is much easier to get a good clean square cut using them.
    The Sharkbite type fittings (available at Lowes and online) are easy to use AND if you change you mind and find a better path to run the tubing, it is easy to disconnect, re-route the tubing, and reconnect.  Jack


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 23, 2008, 11:51:33 AM
 If you have the crimping tool the crimp style is by far the cheaper compare 10 bucks for Sharkbite to 2 for the brass and a buck for polymer for the fitting buy you plently of drain valves the are not that expenseve for Pex


Title: Re: Pex plumbing lines? Size does matter!
Post by: belfert on August 23, 2008, 01:19:26 PM
Sharkbite fittings are at Home Depot too.  I haven't seen them at Lowes but I haven't looked in a year either.

I went with the crimp system initially and some of the crimps leaked for various reasons.  Sharkbite fittings for my whole bus are going to cost $200 at the most.


Title: Re: Pex plumbing lines? Size does matter!
Post by: JackConrad on August 23, 2008, 03:33:57 PM
Last I looked, the crimpers were over $100.00. The thing I don't like about the crimped fittings is that once crimped, that's it, no changing the route the tubing takes.  Just my way, YMMV  Jack


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 23, 2008, 04:10:41 PM
Jack, there is a tool to remove the crimp rings with out damage to the fitting or pipe cost $29.00 fwiw


Title: Re: Pex plumbing lines? Size does matter!
Post by: Nick Badame Refrig/ACC on August 23, 2008, 08:42:53 PM
Jack, there is a tool to remove the crimp rings with out damage to the fitting or pipe cost $29.00 fwiw


Here is one.
http://www.amazon.com/Zurn-Copper-Crimp-Ring-Remover/dp/B000QC3LM6

Nick-


Title: Re: Pex plumbing lines? Size does matter!
Post by: JackConrad on August 24, 2008, 05:27:08 AM
Jack, there is a tool to remove the crimp rings with out damage to the fitting or pipe cost $29.00 fwiw

Thanks!  One thing I really like about this board is that I learn something new everyday.  Now, If I could just remember all this stuff I'm learnin LOL  Jack


Title: Re: Pex plumbing lines? Size does matter!
Post by: NewbeeMC9 on August 24, 2008, 09:15:08 AM
Jack, there is a tool to remove the crimp rings with out damage to the fitting or pipe cost $29.00 fwiw

Thanks!  One thing I really like about this board is that I learn something new everyday.  Now, If I could just remember all this stuff I'm learnin LOL  Jack

I like the board because after I learn it, I don't have to remember it,  I do a search then ask again after i don't find it :D

I used the plastic push fittings at lowes and HD. work on pex, copper & cpvc,   Since my bus i already some what converted and it is easy to remove which i have had to do,  also some spots would not allow crimpers.

also if you forget to put a drain or have a fitting in a low spot, you can still drain it.


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 24, 2008, 10:36:58 AM
NewbeeMC9, there is a tool for that also if you have enough space for the slip on fitting you can crimp it cost about $35.00


Title: Re: Pex plumbing lines? Size does matter!
Post by: JackConrad on August 24, 2008, 11:45:30 AM
NewbeeMC9, there is a tool for that also if you have enough space for the slip on fitting you can crimp it cost about $35.00

Wow another TOOL!  Oops, Paula says I already got enough tools, LOL  Jack


Title: Re: Pex plumbing lines? Size does matter!
Post by: kyle4501 on August 24, 2008, 02:20:51 PM
. . . . . Paula says I already got enough tools, LOL  Jack

You need to educate Paula. There ain't never been no such thing as 'enough tools'!  :o


Title: Re: Pex plumbing lines? Size does matter!
Post by: luvrbus on August 24, 2008, 02:33:40 PM
Jack, I am not trying to give you a bad time about the Pex tools people just tell me all the time that you cannot do this with Pex a product that was design to be crimped.Me I would not use sharkbite or any other push on fitting with Pex but that is my way. Pex is good stuff and easy to work with


Title: Re: Pex plumbing lines? Size does matter!
Post by: JackConrad on August 24, 2008, 04:10:22 PM
Jack, I am not trying to give you a bad time about the Pex tools

No problem.  It is kinda a standing joke.  Everytime I see or hear about a new tool, I seem to think I should add it to my tool inventory.  My wife tries to use reason and explain to me that I really do not need every tool that is made.  Jack


Title: Re: Pex plumbing lines? Size does matter!
Post by: Busted Knuckle on August 24, 2008, 07:09:42 PM
Jack, I am not trying to give you a bad time about the Pex tools

No problem.  It is kinda a standing joke.  Everytime I see or hear about a new tool, I seem to think I should add it to my tool inventory.  My wife tries to use reason and explain to me that I really do not need every tool that is made.  Jack

Jack,
Boy that right there is hard to swallow, & just makes me wonder! Now I ain't never met you and Paula, but I have met alot of people who have. And they all say how great ya'll are, and on and on.
And I do really know Paula is a great person, but now hmmm ya really got me second guessing here. I mean 

"My wife tries to use reason and explain to me that I really do not need every tool that is made."

That is just really hard for a tool junkie like me to take! I think I need to go out and cry with my tools!
I guess it'll be alright after all you guys hve been a great couple all these yrs! And love must have something to do with it, but I feel deeply for ya! Cause busnuts needs tools & LOTS OF 'EM! ;D  BK  ;D


Title: Re: Pex plumbing lines? Size does matter!
Post by: NewbeeMC9 on August 24, 2008, 07:58:21 PM
Jack, I am not trying to give you a bad time about the Pex tools

No problem.  It is kinda a standing joke.  Everytime I see or hear about a new tool, I seem to think I should add it to my tool inventory.  My wife tries to use reason and explain to me that I really do not need every tool that is made.  Jack

Jack, Next time try , Cause your haircut only cost ______ dollars and the tool makes you feel better about yourself :D


Luvrbus,  i like the crimp, but i knew i would be taking stuff a part again and again as i fix different things so iI used the push fittings on the bus,  my last house had the crimp fittings( but i had somebody do it because i wanted it done quicker than me doing it and old galvanized was being replaced in a crammped, extreemely dusty crawlspace).  Plus i didn't need may fittings for the bus so it was cheaper than tool. 

All these tools and fiittings seems like a good article for BC MAG  with pic otools bing used and fittings etc



Title: Re: Pex plumbing lines? Size does matter!
Post by: David Anderson on August 30, 2008, 01:24:49 PM
This relates to PEX, so I figured I'd post it here and bring the thread back to the top.  I just watched an "Ask This Old House" segment on PBS where Richard Trethewey went to Raleigh NC to work with a plumber who makes a living replacing polybutylene pipe in houses.  That is all this company does.  Richard briefly explained the history of Polybutelene's origination as the great plumbing solution of the 1970's.  Here we are, 30 years later replacing all this cracking and leaking poly pipe and replacing it while class actions lawyers sue for millions and consumers get a $5 coupon on their next purchase or something or other the bankrupt manufacturer now makes. 

The segment had Richard and the plumbing contractor show some closeup views of the cracking pipe and the leaking fittings.  It is mostly the crimps that failed allowing leakage at tees and ells.  The crimps look alot like the copper and stainless crimps we see today on PEX fittings.   What will keep a repeat of this in 30 years in all these homes?   I do like the fact that PEX is mainly done with home runs and fittings are minimal and isolated at the manifold and the fixture.  If the pipe lasts for 50+ years then replacing fittings will be much easier if that is the weakest point in the system. 

The house profiled in the segment had fittings in the ceiling, walls, and crawl space.  They had so much of the sheetrock removed.  It must have been a huge expense.   The system was repaced with all CPVC, not PEX.  I guess just the choice of the local plumber, or perhaps he doesn't trust PEX.  No explanation was given, though I know Richard Trethewey loves to use PEX. 

Just a thought to bring up.

David