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snowman
07-05-2009, 09:03 PM
I've always been a copper man myself, but I've got a project right now that has me running hot and cold water from one side of the house to the other, with a minimal amount of branches.

Anybody used the stuff? Any bad reviews of it? The plumbers I've talked to love it, as it's quick to install and supposedly lasts forever.

How about the crimpers...I see the depot has a 25 dollar crimper that you squeeze together with a pair of vise grips. Including the price of the crimper, the whole project can be done for less than half of what I'd have in running the cold water alone.

Thoughts?

Evan
07-05-2009, 09:16 PM
I used it to plumb my solar collector. Never again. Trying to straighten that stuff enough to snake it in a reasonable manner along the floor joists above in the basement was like fighting with heavy spring steel banding. This was the 1/2" stuff, I would hate to see what the larger sizes are like.

Lew Hartswick
07-05-2009, 09:22 PM
My nephew bough a two peice "manufactured" house about 10 years
ago with that piping instaled (red for hot and blue for cold). He later
wanted to add some more taps and bought a regular crimper and the
tubing and the required fittings and proceeded to do the work. Now he
is a pretty versital fellow but had no troubles and its still working fine.
I have seen the parts in one of the "big box" stores somewhere so
I'd say go for it, but do take real care in the crimping operation.
...lew...

edit: Well as Evan says it is a "little" stiff. :-)

Fasttrack
07-05-2009, 09:28 PM
I ran 300 yards of 1" pex tubing underground for a hydrant near the shop. I didn't have any problems unrolling it like Evan mentioned. In fact, it was pretty painless and very cheap!

Maybe it's just so damn cold up where Evan is, he couldn't get the tubing to soften up enough :D

snowman
07-05-2009, 09:39 PM
Evan,

Were you trying to snake it through an enclosed space? That is the one complaint I have heard with it, is that it is "too flexible"....meaning it's difficult to keep straight, and installs will look crappy.

My install will be hidden behind a drop cieling and a wall, I'm not overly concerned.

Liger Zero
07-05-2009, 09:45 PM
Pex is a bastard to straighten out. I turn a fair bit of it on the lathe,

My trick is to heat it a bit with the wife's hair drier and flex it by hand.

'course being an old Master Of The Plastiks I have The Touch. Polymers... they respect me. [bull****=off] :D

Evan
07-05-2009, 09:46 PM
The stuff came in a tight roll about 18" diameter and it wanted to stay that way. If I let go of it it would coil up again like a coiled air hose. It is difficult to keep straight alright but not because it is too flexible, but too springy.

Fasttrack
07-05-2009, 10:01 PM
ahh - ours came on one of those large wooden spools. All I had to do was kick it along next to the trench and the pex laid down pretty well in the bottom.

MTNGUN
07-05-2009, 10:35 PM
After using pex, I won't go back to copper or threaded pipe. I use pex for air lines, too.

Bruce Griffing
07-05-2009, 11:06 PM
In water supply applications, PEX will often survive freezing tho I don't think it is guaranteed to do so. Copper is much less likely to survive the same test.

Jim Shaper
07-06-2009, 01:16 AM
How well would pex work in a solar assist pre-heater application?

I'm thinking of making a "radiator" grid attached to the roof to cycle the heated water through the tank during the day rather than having the flame maintain the temp.

If the temp in the attic is any indication, it could save a ton of money on the gas bill.

I've been thinking it would need to be copper due to rust/food safe issues.

dp
07-06-2009, 01:27 AM
The stuff came in a tight roll about 18" diameter and it wanted to stay that way. If I let go of it it would coil up again like a coiled air hose. It is difficult to keep straight alright but not because it is too flexible, but too springy.

I bought and later tossed out a 100' roll of 2" poly pipe. I was going to trench it in and plumb sprinklers in my rather large back yard (not quite as large as yours). It was in 4' loops and would not uncoil no matter what I tried. I chucked it and the idea and now just run hoses :)

Evan
07-06-2009, 03:19 AM
Jim,

It freezes where you are so you should use a heat exchanger system instead of trying to run a circulating loop directly with the water supply. Trying to run a loop with full pressure water is asking for problems in the way of leaks and will require a sealed circulating pump that can operate closed loop at 100 psi or more.

If you use a heat exchanger the solar loop can run on non-toxic etheylene glycol antifreeze at no more pressure than it takes to reach the top of the loop. The exchanger tank will act as a heat sink and can operate at zero pressure. If you design it right you can get away without the antifreeze. If there are no parts of the loop that can act as a P trap then it will automatically drain down when the pump is turned off as long as one end has a siphon break at the storage tank and the pump isn't positive displacement.

For the potable water part of the heat exchanger use an unbroken length of rated pipe in a coil. The tank can be no more than a poly garbage can or better a heavy duty poly 55 gallon food safe drum used for shipping juice. That is what I am using. I just had a problem Sunday with the exhanger pressure loop developing a leak at a seam in the multi-part heat exchanger that sits in the tank. It was really warm here and sunny all day and the exchanger tank reached nearly 100F which weakened the plastic and blew out a sealed connection. This produced an overflow but no damage was done because there is a floor drain nearby and I caught it in a couple of minutes because I have an overfill alarm on the exchanger tank.

I am going to replace the pressure side with a 100 foot coil of ABS plastic pipe I already have.

NAMPeters
07-06-2009, 12:16 PM
PEX tubing is made to copper tube size (CTS), thus is size compatible with copper tubing, CPVC and the old PB tubing. The advantage of this is that these can be mixed using push on fittings making splicing and repair of these systems easy, also push on fittings can be used in place of crimped style fittings. These fittings come in both plastic and metal styles; Graingers and ACE are suppliers. Another plus for these push on fittings is that they are reusable.

Liger Zero
07-06-2009, 12:18 PM
See now I just buy 12' sections from the hardware store. I don't deal with the coiled stuff.

camdigger
07-06-2009, 12:31 PM
See now I just buy 12' sections from the hardware store. I don't deal with the coiled stuff.

X2

One Pro plumber used straight lengths +/- 10' long to do all his work, the other used coiled tubing and a few plastic ring style holders. With adequate support, neither job has given any trouble. I doubt our home has a dozen soldered connections. The ones I can find are on the header for the infloor heat.

Plumbing PEX is available with the crimp ring and "Memory" couplers. Our whole hose (new construction) has PEX plumbing with mostly the Memory couplers.

FWIW, portable wellsite trailers have used PEX (or PVC - grey in color) for 20 years. They went to the plastic for its' resistance to freeze damage ( the units are hard to drain correctly, and not everyone is completely diligent about it.)

On another note, there are new plug in connectors for PEX for valves, etc. just cut the tubing square and jam the tubing in - very similar to the air fittings that have been available for ever. I haven't used those intended for plumbing, but I worked with lots of the air fittings over the last 20 years.

Mcruff
07-06-2009, 12:37 PM
The company I work for manufactures it in our sister plant right beside us. I bought a 300' roll to use as airlines last year. The stuff will try to coil back up and is diificult to deal with. I left mine out in the hot sun tied from garage to the fence for about 3 hours before installing it. It stayed just fine. We do also make 20' sticks of it though. The stuff we make is called Raupex made here in Cullman Ala. As far as plumbing it is far superior to any copper tubing that I have seen. Our plant was built in 1995 and the whole plant is plumbed in the stuff including alot of air lines. To my knowlege there has never been a rupture that wasn't caused from an insane forklift driver running into the stuff on the poles.

boslab
07-06-2009, 12:55 PM
over the pond we use a lot of combi type boilers that have pressurised heating at about 1.5-2 bar, got a push fit in the bathroom [PEX], slight weep, as you do touched it to see how much was leaking, the fitting blew off and i got a chest full of water at 70-80 deg C, the skin top layer peeled off the next day, i thought a steelplant was dangerous!, i still have PEX pushfit but i'm very carefull with them now, eventuallu i think i'll replace with copper!
regards
mark

madman
07-06-2009, 01:22 PM
DONT use the orange pex stuff. I used 800 feet of pex 9White clear colour) in my homemade hydronic shop floor heating system and it worked out very well. I bought the tool like pliers which werent that xpensive. I used a lot of rebar and mesh (got 2 tons of it free) and just tied like a 1000 nyties almost everywhere to hold the pex tube to the rebar,. The system exeeded my expectations. I am looking forward to finally finishing the drywall and painting and doing some new projects in theshop soon.

Liger Zero
07-06-2009, 02:02 PM
The company I work for manufactures it in our sister plant right beside us. I bought a 300' roll to use as airlines last year. The stuff will try to coil back up and is diificult to deal with. I left mine out in the hot sun tied from garage to the fence for about 3 hours before installing it. It stayed just fine. We do also make 20' sticks of it though. The stuff we make is called Raupex made here in Cullman Ala. As far as plumbing it is far superior to any copper tubing that I have seen. Our plant was built in 1995 and the whole plant is plumbed in the stuff including alot of air lines. To my knowlege there has never been a rupture that wasn't caused from an insane forklift driver running into the stuff on the poles.

All forklift drivers are insane. :p

motorcyclemac
07-06-2009, 03:34 PM
I recently had to make a repair to the shower in our master bath. There was little room to work in the wall. The original mounting for the valve body wasn't going to work with the replacement valve and thus I had to remove the pluming and shower head riser and start over. I used the white / clear pex. I bought a 12 foot stick and used some pushlock "shark bite" connectors to adapt to 1/2 inch pipe thread. It was the most wonderful, easy leak proof install I have ever done. I loved it. I bought a special pair of pipe cutter pliers from Ridgid to get clean square cuts. I can see where this was most of the reason it went so well. Clean cuts are a must.

Good stuff. I am sold on using it for water. I don't know about air....but I suspect it would be ok...as if it did fail..there should not be an issue with schrapnel. It is rather soft and I suspect it would pop at a joint rather than explode from being brittle.

Cheers
Mac.

j king
07-06-2009, 04:48 PM
I installed an outdoor wood stove and installed the insulated pex. That stuff is terrible to work with.It wants to coil and yet you cant bend it. Its tuff to lay.

I ran some inside the house for the same job. 1" and it was a wrestling match to work with.There must be tricks for working with it.

Jim Shaper
07-06-2009, 05:00 PM
Good points about the heat exchanger Evan. The problem is that I want to minimize the space the system occupies within the house. I do realize there's no free lunch. :)

In the winter, most years, we don't get enough heat in the attic to melt the snow cover, so freezing is a potential issue. I was thinking it would be a system onto itself so that it could be shut down and drained just like the yard sprinklers.

Quetico Bob
07-06-2009, 05:08 PM
Good stuff, but rent the proper crimpers or buy. :eek: Last one I used looked like a bolt cutter on steroids.

Cheers, Bob

drof34
07-06-2009, 07:00 PM
Back in the 80's, I built a new house with a concrete slab floor.
Trying to think ahead about water lines and their eventual leaking under the concrete, I came up with the idea of placing flexible copper tubing inside much larger PVC pipe with long radius ells(1/2" cu inside 1-1/4 PVC) under the slab.

After about 15 or so years, 3 of them have leaked( electrolysis). It required a tractor to pull out the old tubing and their was no way I was going to get new copper tubing pushed or pulled back in place. But pex worked great and has for 7 or 8 years now.

Jim W.

derekm
07-06-2009, 07:47 PM
I use it for:

The central heating
The automated garden watering system in the greenhouse
Hot and cold water in the house
Compressed air to the shop from the compressor (25m run)
soluble coolant around the workshop (central pump) a 10m run


Its very good ,99 out of 100 joints are fine rock solid - The other one might weep then fly off if you touch it. If its weeping dont fiddle with it under pressure. The weep is saying its duff - replace it.

motorcyclemac
07-07-2009, 12:20 PM
. The weep is saying its duff - replace it.

I get a boot out of some of the terms that come from over the pond.

Cheers
Mac.

Jim Shaper
07-07-2009, 02:35 PM
It's 109F on the underside of the roofs 1/2" plywood sheathing (IR thermometer reading from inside the attic), while it's only 80F outside right now. It's 100F inside the attic.

So even if you just circulated your water through the attic before sending it into the heater, you'd potentially gain 40F (assuming 80% efficiency).

Granted condensation would be problematic by doing it that way, so an external system would be superior.

Evan
07-07-2009, 02:44 PM
However you do it it is sure worth doing. We just got the lowest electric bill in 20 years and that is with the various price hikes since then. The bill is $95 for two months use. During that period we had a three week warm spell and the tank was averaging around 90 degrees F. That bill is for a full 35% year over year reduction in consumption for the same time period.

kf2qd
07-07-2009, 08:45 PM
There are at least 2 types of PEX tubing. For heating systems I have used K-PEX which had a layer aluminum foil between 2 layers of PEX. The aluminum layer prevents the migration of oxygen into the heating water and thus helps with corrosion control. The other type that is used for household plumbing and does not have the aluminum layer as oxygen and corrosion are not a problem as the water flows out the tap. The water supply Pex came in red and blue so you can keep track of hot and cold water.

I have used fittings that had a brass tube on the inside of the tube and used a collet on the outside. No leaks and no creep.

Jim Shaper
07-07-2009, 09:10 PM
How well does pex handle UV exposure?

Evan
07-07-2009, 09:26 PM
If it is anything like white PVC then it is very good. I pulled 350 feet of PVC out of my well when I replaced the pump about 15 years ago and since the pump was out I replaced everything down the hole. I sawed up the pipe into sections and they have been sitting in a stack outside ever since. I needed a piece recently and expected to find it useless but instead it is just as flexible as the day it was new. White is a very good reflector of UV as well as visible light.

Mcruff
07-07-2009, 11:32 PM
How well does pex handle UV exposure?
The blue (coating) is actually for UV protection and not to identify hot or cold water. The blue is what I ran my air lines in since it is exposed to sunlight on some of the walls.

Evan
07-08-2009, 12:06 AM
I was looking up PEX UV tolerance and it is poor. Even the UV protected types are only rated for 6 months exposure to sunlight.

I found no indication that the color of the tubing has anything to do with UV protection and the manufacturers all say that the red/blue is a hot/cold color code.


HydroPEX Tubing is designed for use in potable plumbing systems. HydroPEX Tubing meets ASTM F876/877, SDR 9, and is pressure tested to 180F at 100 psi. HydroPEX Tubing comes in red and blue to distinguish hot and cold water lines.

http://www.pexsupply.com/PEX-Tubing-516000

Mcruff
07-08-2009, 03:12 AM
I found no indication that the color of the tubing has anything to do with UV protection and the manufacturers all say that the red/blue is a hot/cold color code.

Well I went and checked a while ago next door.
It seems that when they 1st started molding the blue it was UV protected only, now both red and blue are UV protected. The box I have is specificaly marked UV and I know that they used to only make the clear and blue in our plant next door. The red used to be marked o2 barrier only but now it is listed as UV protected also.

gellfex
07-08-2009, 04:33 PM
There are at least 2 types of PEX tubing. For heating systems I have used K-PEX which had a layer aluminum foil between 2 layers of PEX. The aluminum layer prevents the migration of oxygen into the heating water and thus helps with corrosion control. The other type that is used for household plumbing and does not have the aluminum layer as oxygen and corrosion are not a problem as the water flows out the tap. The water supply Pex came in red and blue so you can keep track of hot and cold water.

I have used fittings that had a brass tube on the inside of the tube and used a collet on the outside. No leaks and no creep.

I used the AL core type for a hanging radiant floor install, you neglect to mention it holds it shape where you put it like a soft copper pipe, so it's not a constant wrestling match. So if you need to blind feed it, like I did, it's worth the extra cost. I can't see the other stuff useful for other than new construction with open walls.

rustyswarf
07-08-2009, 07:40 PM
Snowman, I sell the stuff at work. Sell 20 ft. straight sticks all the way to 500 ft. rolls. Get a proper crimping tool and make sure it is calibrated. They usually are adjustable for wear, and come with a guage to properly set them. Just keep the stuff out of direct sunlight. UV rays will do bad things to pex tubing. It does not matter what a salesman tells you; if you leave pex in direct sunlight, expect a split and a leak in about two years. Otherwise, the stuff is cheaper than copper, and alot faster to install in a new home. Contractors tell me they can get two men to pipe two entire houses and be on the way to the third one--and the copper guy has not finished his first house. I have not used it in my home yet, but only because the house was done in copper, and I'm keeping it all the same. Friend of mine plumbed his new shed, equipped with a complete 35 mm film developing darkroom 7 years ago. No problems.

Jim Shaper
07-08-2009, 08:07 PM
I was considering it for the flexible joints in the system, but not being able to be exposed outside rules it out.

Evan
07-08-2009, 09:28 PM
I only used it for the inside portion of my solar heater plumbing. The outside portion is connected with high quality multi ply insulated garden hose that I managed to find for 25 cents per foot in random roll end lengths. :D No piece is longer than 24 feet but they all have machined end fittings installed.

kvom
07-09-2009, 11:53 AM
My garage/apartment build used white pex for all water supplies. I bought straight sticks, so all bends used 90-degree crimp fittings. Connection to the home copper supply line was via a Gator-Bite. Connections to toilet and basins was via compression valves.