Pex master list

[ALANSD]

Since there are many like me who will redo their old copper with PEX- And are somewhat plumbing challenged. I would appreciate a master list of tips from those who have done this job. Maybe 10 or so tips to get it done right the first time.
In my case the copper is split from the po not winterizing..26' 66 Overlander.
Gonna make temporary fixes for now then do it all over the winter.
Maybe this could be a sticky thread if it works.

[mimiandrews]

PEX itself is really easy. I found only two real challenges when we replaced all the copper in our Safari with PEX.

First, understand the system and sketch yourself a diagram of the whole thing. One sketch for hot, one for cold, detail for the complicated sections near the water pump, etc. Once the old lines are a pile of copper headed for the recycling yard (good prices, but they'll want ID), it's too late to know where they originally went.

I had to re-design the section near the water pump somewhat, because copper fittings will turn tighter corners than PEX fittings will. Just get the picture in your head and make up something that will do the same job and fit the space.

Second, if you use the crimped fittings like we did, plan to sub-assemble the sections of plumbing that are in tight places. The PEX crimp tool needs room to operate, and a trailer is full of places where it won't. Plan the sub-assembly, make it up with measurements and trial fittings, lay it in place, and make the last connection where there is room for the tool.

I've read of a PEX tool that works in close places on the Forums lately, but didn't have one when we did our trailer.

The job is more "head scratchin" than actual work. Good luck.

[ALANSD]

THANKS, that is a good start to getting me on the right track. Fortunately a frined did his trailer recently so I will be hitting him up for some advice as well.

[markdoane]

Make sure all lines are pitched toward the low point drains. Pex is more flexible than copper, so be sure you use enough anchor clips to prevent sagging.

Use Sharkbite (or equivalent) fittings at appliances connections like the water heater and pump so you can remove them for service. Also use them where its hard to get at the fitting with the crimping tool. Wrap a piece of masking tape around the tubing to show the full insertion depth in Sharkbite fittings.

If you loan out your crimping tool, don't expect to ever see it again.

Dry-fit everything.

[wahoonc]

If using Sharkbite or similar fittings, make sure the ends are clean (no burrs) and SQUARE, otherwise you will have problems. FWIW I would use the straight sticks of PEX rather than the rolls for an Airstream. I also plan to use the color coded line for hot and cold.

Aaron

[DanB]

Tip: Allow for more money!

The fittings are expensive! But they are great fun! I use the lowes version of Sharkbite. I've never had a failure or leak. Plus, as I'm going to be going thru a major renovation, I'll be able to easily take apart the plumbing and reuse the fittings.

[Mikethefixit]

Alan
I ran new Hot line to the galley,from the rear all the way up,PEX went around the curbside curve NP. I renewed the lines to the lavatory and shower. Like yours all had been frozen by one of the PO's. Third owner here. I used all Sharkbite and GatorBite fittings from both HD and Lowes. The PEX line slide thru the bulkheads NP.
You can dry fit everything and if ya make a mistake on tubing lengths ya just use the little tool and take the fittings apart and start over. PEX Tubing cuts easy with a utility knife.I dont think its worth the cost to buy or even rent the crimp tools ($90 bucks or more) to do a one time job. YES the fitting are expensive.but you can put tubing together where ya cant get the crimp tool.
Fittings come/Connector/Tee/ 90's/and Caps. .
One thing to remember at least what I found was,the copper in my 77 was soft(came in a roll) . Soft copper 1/2 and Ridged Copper1/2 are not the same outside diameter. BECAREFUL I had to learn the hard way.
I would really suggest using Sharkbite or GatorBite fittings it makes it so easy.
GOOD LUCK and GOOD PLUMBING
Roger

[bryanl]

Using a tubing cutter to get nice clean, square ends to the tubing is probably the critical skill.

Choosing your fittings will also greatly impact your effort. I prefer the 'Flair It' fittings as they are re-usable and include both inside and outside the tubing (slide tube over barb and tighten nut) connections (see how to use guide). If find iPlumb.tv - PEX Fittings Flair It Bulk a good source for fittings and a local hardware or RV store should also have a fairly decent selection. A search indicates there are even some videos available to help see how these are used.

I use a heat gun to heat up the PEX (very carefully) to make it easier to jam onto the Flair It barbs.

The Sharkbite type fittings need more attention to the tubing end being just right but are ideal if you need to interface with some existing copper.

The bend radius for PEX tubing is 4 times the diameter. Going around the curved corners of the Airstream works well but going around water heaters and pumps and making corners in tight spots often works better with an elbow.

Use color coded PEX, blue for cold and red for hot. I usually run the water pump to heater as half inch tubing and everything else as 3/8.

Do make sure to install a water heater bypass and a pump siphon to make winterizing easier.

Do plan ahead. Sketch everything out on a piece of paper and figure out a fittings diagram so you can get the right number of the right size. Anticipate missing something in your plans and be prepared. Have some spare stuff to take care of 'educational experiments' and keep in mind that the supplies aren't really that expensive so a mistake or two shouldn't be a disaster.

Take your time and take care and you should get a good result.

[ALANSD]

Great tips! Wen to Ace today just to check it out, the one I went to did not carry PEX.
Where can you get the straight sticks and what lengths does that come in?

I might consider leaving the long copper under the streetside bed. I am really conscious about winterizing so if it's not leaking there now, I would be ok.
Found out my hot water heater is leaking out the drain valve. does not want to tighten enough...guess it needs a new screw in piece?

[Mikethefixit]

ALANSD
Lowes or HD 1/2 is what ya need and it comes in 10 ft sticks. Here its only 3 or 4 bucks a 10fter. The Sharkbite or Gatorbite fittings I told ya about are around 4 to 5 buck a throw. ADDS up real fast. I had some 1/2 ridge copper and filled some of the spaces. Sharkbite fittings will work with copper,PEX and 1 of the PVC's . Sorry cant remember which one,the one I didnt use,LOL.
Great links Bryan, and ALANSD everything Bryan Said.

[ALANSD]

Ok will be buying the pex soon.. Are most sink and other connections 3/8 or 1/2"?
So if I buy 1/2" pex I will know what size connectors to order.
Also what do you all think about a small manifold?

[easyride]

What I did on my 73 was build 2 manifolds in the trunk after feeding the water heater,1/2 with angle stops for all fixtures,then ran 1/4"to all the fixtures.Needed plastic ferrules for the pex,3/8 unions to tie onto the k.s.,lavatory,and toilet. For the shower needed 1/2x 3/8 compression union.
Now all shuts are in the trunk. Dave

[Aviator]

Alan, When you finish the project, would you please post a list of material used?

[Mrcrowley]

I used Shark bite in mine they are great because they fit in hard to get places. You just push in until it stops then give a good tug out done deal . I tried the compression type but they were real big and put strain on the pex making them leak. Instead of the huge pressure regulator I put as a hose type one the hose inlet works great 30 to 40 PSI .

[ALANSD]

Originally Posted by Aviator

Alan, When you finish the project, would you please post a list of material used?

will do . I am ordering a marine type hose inlet to mount also. I hate the hose hanging out of the trailer. Looks like the I will buy is 1/2 " pex tubing with Sharkbite connectors ...Maybe a small manifold but I figure less than 10 connections total. I am guessing all the sinks take 3/8 connetions?

2 Kitchen 2 bath faucet, 2 shower, 1 toilet, 1 water heater, maybe 1 outside water.

I will be sketching this weekend while I pull out my old Dometic fridge.

[j Z]

I plan on doing PEX in my trailer as well. I did my entire house in PEX and it is a great system. Instead of buying both red and blue to hot and cold runs, I bought red and blue electrical tape and put a band on the fittings to distinguish them. That way I only had to buy 100' rolls of white pipe in each size. For making tight curves, use one of the plastic braces or a 90 for tighter curves around the water heater, etc. My house system has very few fittings, just a few manifolds with direct runs to each fixture. It makes for a very quiet and efficient system.

I went with Uponor fittings for my house and bought the expander tool for $300. I would consider selling it after my projects are done, if ever. FWIW the Uponor tools sell for 90% of retail on eBay.

Anyone use heat trace tape on their pex to keep everything warm in winter?

Has anyone installed an on-demand water heater such as the Girard?

Cheers,

JZ

[Aviator]

Pardon my lack of knowledge, but what is "heat trace tape"? I was thinking of insulating my runs with the foam sleeves.

[Crusty]

The Quick-Cinch clamps available at Lowe's for use with PEX and brass barb fittings work great (better than the copper rings) and the crimpers for them are affordable (~$40). They also stock a clamp remover if you need to try again because you weren't paying enough attention and poorly cinched a clamp.

[adwriter73]

Does anyone know how to test your water lines to make sure there are no leaks after you run new PEX? I used the Sharkbite fittings and want to make sure all the connections are good before I put everything back together.

[ALANSD]

good info guys ...