How important is oxygen barrier pipe?

[Como]

$10 ish a day where I am buys about 100kw

300,000btus

12,000 an hour, double it for peak

So not that large a stove.

Stoves are not cheap, chimney for ours cost the same as the stove.

 

[Murphy2000]

Only 10% or less will even be exposed to air as the rest will be under ground.

Ever wonder what worms breath?

And boy oh boy do they breath!

I grow worms by the thousands and use their poop to water my garden. You can't buy fertilizer that good.

 

[cljimmy72]

Forgive me please as I am a little new to this. Trying to set up a system for a 24 x 40 workshop which already has the pex in the floor. Radiantec from Vermont designed my system and sold me all the necessary goods for it. I am not sure if the pex has the oxygen barrier or not ( I will call them and find out). Isn't oxygen already present in a system using water as the heat transferring fluid. After all water is H20. Without taking up too much of someone's time could you explain this to me.

 

[sdrobertson]

Forgive me please as I am a little new to this. Trying to set up a system for a 24 x 40 workshop which already has the pex in the floor. Radiantec from Vermont designed my system and sold me all the necessary goods for it. I am not sure if the pex has the oxygen barrier or not ( I will call them and find out). Isn't oxygen already present in a system using water as the heat transferring fluid. After all water is H20. Without taking up too much of someone's time could you explain this to me.

Welcome to the forum!

There is extra oxygen in water. When the extra oxygen is used up (rusting) and the water system is closed (pressurized) then the water will not allow anymore oxygen to leave the water to rust the system. Kind of like a lake that doesn't have enough oxygen in it to support fish.

 

[millerblt]

After reading all of the posts on O2 barrier pex I started to get curious myself is there is a difference? I have a machine designed to test for leaks in any material, we weld aircraft engine parts and have to test them for leaks when we have completed our work. The tester draws a vacuum on the part and then we flood the outside of the part with Helium, if the parts leak the Helium is detected by a mass spectrometer inside the machine.
This morning my curiosity got the better of me and I tested a piece of my underground O2 barrier pex and as I suspected I detected no leaking at the maximum rate my machine will detect Helium, ( 1x10-9 torr ).
As Helium molecules are much smaller than O2 molecules I would think this is an almost perfect protection, although every material leaks to some extent. This machine is closely calibrated as we do use it daily for all the major aircraft engine manufactures including the space shuttle. Although I do not have a piece of non barrier pex to test my guess based on other plastics I have tested is that I would get the same results if I tested the non barrier pipe.
I will try to find some non barrier to test and post my results if I can. There might be more to this than I am aware but I thought I would share my test results.

 

[in hot water]

After reading all of the posts on O2 barrier pex I started to get curious myself is there is a difference? I have a machine designed to test for leaks in any material, we weld aircraft engine parts and have to test them for leaks when we have completed our work. The tester draws a vacuum on the part and then we flood the outside of the part with Helium, if the parts leak the Helium is detected by a mass spectrometer inside the machine.
This morning my curiosity got the better of me and I tested a piece of my underground O2 barrier pex and as I suspected I detected no leaking at the maximum rate my machine will detect Helium, ( 1x10-9 torr ).
As Helium molecules are much smaller than O2 molecules I would think this is an almost perfect protection, although every material leaks to some extent. This machine is closely calibrated as we do use it daily for all the major aircraft engine manufactures including the space shuttle. Although I do not have a piece of non barrier pex to test my guess based on other plastics I have tested is that I would get the same results if I tested the non barrier pipe.
I will try to find some non barrier to test and post my results if I can. There might be more to this than I am aware but I thought I would share my test results.

Here is some info on the standard and amount of O2 they test to.

Tomas Lenman "Mr. Pex" has some good info on pex tube at www.mrpexsystems.com most of his book Water and Pipes is on his site. One of the early pioneers on pex tube he knows a lot about O2 and pex.

 

[btuser]

Only 10% or less will even be exposed to air as the rest will be under ground.

Ever wonder what worms breath?

I bet they don't do well in closed cell insulation. Maybe he's planning on insulating with packing peanuts?

 

[bigburner]

It's got to make a difference on the amount of pipe ya have also. Got 1 1/2 miles of the stuff here. [all ox barrier or PAP]. Some in concrete, some in the ground and some just hanging around.

 

[heaterman]

Only 10% or less will even be exposed to air as the rest will be under ground.

Ever wonder what worms breath?

I bet they don't do well in closed cell insulation. Maybe he's planning on insulating with packing peanuts?

I have never seen any information on the oxygen permeability of closed cell foam. I know is it closed cell to worms and water but an oxygen molecule is far smaller than either. Personally I would want to see it in writing before I trusted the integrity of my system to an assumption. ......Maybe I should go live in Missouri, the "show me" state along with Hot Rod.

 

[free75degrees]

After reading all of the posts on O2 barrier pex I started to get curious myself is there is a difference? I have a machine designed to test for leaks in any material, we weld aircraft engine parts and have to test them for leaks when we have completed our work. The tester draws a vacuum on the part and then we flood the outside of the part with Helium, if the parts leak the Helium is detected by a mass spectrometer inside the machine.
This morning my curiosity got the better of me and I tested a piece of my underground O2 barrier pex and as I suspected I detected no leaking at the maximum rate my machine will detect Helium, ( 1x10-9 torr ).
As Helium molecules are much smaller than O2 molecules I would think this is an almost perfect protection, although every material leaks to some extent. This machine is closely calibrated as we do use it daily for all the major aircraft engine manufactures including the space shuttle. Although I do not have a piece of non barrier pex to test my guess based on other plastics I have tested is that I would get the same results if I tested the non barrier pipe.
I will try to find some non barrier to test and post my results if I can. There might be more to this than I am aware but I thought I would share my test results.

A couple things have been mentioned to make sure this would be a fair test, so I'll summarize: (plus add a couple)
- The length of the tube is very important. If an actual system has hundreds of feet and you test a foot or so of length that's greater than 100x difference, so you could get misleading results.
- Temperature is critical. You'd really want to get the pipe up to 180* or so.
- Time is also very important. The issue is not leaks, so you shouldn't expect a quick result. Diffusion is a slow process. I don't know the numbers, but you might need to wait days, weeks, or maybe even more. A heating system has that much time and more.
- I assume the spectrometer can detect oxygen? If so, why not do the test with normal air. Better to remove as many variables as possible from the experiment. Plus you'd hate to get a positive result and wonder if it was just because of the helium being smaller molecules.

 

[heaterman]

After reading all of the posts on O2 barrier pex I started to get curious myself is there is a difference? I have a machine designed to test for leaks in any material, we weld aircraft engine parts and have to test them for leaks when we have completed our work. The tester draws a vacuum on the part and then we flood the outside of the part with Helium, if the parts leak the Helium is detected by a mass spectrometer inside the machine.
This morning my curiosity got the better of me and I tested a piece of my underground O2 barrier pex and as I suspected I detected no leaking at the maximum rate my machine will detect Helium, ( 1x10-9 torr ).
As Helium molecules are much smaller than O2 molecules I would think this is an almost perfect protection, although every material leaks to some extent. This machine is closely calibrated as we do use it daily for all the major aircraft engine manufactures including the space shuttle. Although I do not have a piece of non barrier pex to test my guess based on other plastics I have tested is that I would get the same results if I tested the non barrier pipe.
I will try to find some non barrier to test and post my results if I can. There might be more to this than I am aware but I thought I would share my test results.

A couple things have been mentioned to make sure this would be a fair test, so I'll summarize: (plus add a couple)
- The length of the tube is very important. If an actual system has hundreds of feet and you test a foot or so of length that's greater than 100x difference, so you could get misleading results.
- Temperature is critical. You'd really want to get the pipe up to 180* or so.
- Time is also very important. The issue is not leaks, so you shouldn't expect a quick result. Diffusion is a slow process. I don't know the numbers, but you might need to wait days, weeks, or maybe even more. A heating system has that much time and more.
- I assume the spectrometer can detect oxygen? If so, why not do the test with normal air. Better to remove as many variables as possible from the experiment. Plus you'd hate to get a positive result and wonder if it was just because of the helium being smaller molecules.

That's all been done and if one does a little searching on the www the specs for oxygen diffusion are readily available. The specs are mainly from Europe under DIN standards. The jury of scientific method is in and has spoken on this many moons ago. Non barrier tube is not suitable for heating use if you want long and trouble free life from your heating system. One can definitely argue the total surface area of the tube in the system being a mitigating factor but it happens to some degree in any case. Personally I have seen two infloor systems so plugged up they could not be cleaned and had to be abandoned.

 

[DaveBP]

I assume the spectrometer can detect oxygen? If so, why not do the test with normal air. Better to remove as many variables as possible from the experiment. Plus you’d hate to get a positive result and wonder if it was just because of the helium being smaller molecules.

If his helium sniffer is anything like the one I was involved with 40 years ago it only detects helium.

And helium IS the smallest molecule. It is a single atom and the second smallest atom at that. (don't get started on the 'size' of an atom). The idea is that it can squeek through where nothing else could fit.

Other than this little nit-pick, 'free73' nails the argument for barrier PEX despite the leak test of non-barrier.

If someone really doesn't want to use barrier PEX... well ... don't . But as soon as you've finished arguing with the entire industry about that, start researching water treatment and start aguing about why that is a fallacy, too.

 

[Digger873]

Ok so lets summarize.
So O2 "MAY" diffuse through the pipe and "MAY" cause corrosion according to the post by heaterman.
I will concede once again that O2 barrier pipe would be better.
But I would like to remind you all that the question was "is it really necessary".
Some of you say its better but corrosion can be controlled with water treatment. I think this is probably an accurate statement.

Some of you say or imply if a guy doesnt use barrier pipe he shouldnt even have a boiler because it just wont work right.
I sure feel sorry for all those guys out there with open systems, poor suckers should just just shut em down untill they can afford a proper closed system with O2 barrier pipe, I mean my God what were they thinking.

I am one of those poor ignorant slobs in the trades. I have put miles of pipe in the ground, and while I dont do boiler work, I am not a stranger to water running through pipes of all kinds. I dont doubt that you all that do this for a living have seen thing rust out and systems plugged up beyond repair. But to say the only cause of these problems was lack of O2 barrier pipe is really a stretch.
There are a lot of things that can cause corrosion and plug up a system, I would be willing to bet that even a system that has O2 barrier pipe is going to require treatment and maintenance, and is going to get some corrosion.
I happen to know that water/ can be run through steel pipes at 180 F for years without becoming unusable, as long as you maintain it and or treat it.
I asked this question in order to find out if maybe there was something about the pex I didnt know about that caused maybe more than normal O2 to get in the water or something allong those lines.
I have my answer, and here it is.
NO O2 barrier pipe is not really necessary. It is better to be sure, but there are other ways to deal with corrosion as well. Water treatment (which has to be done anyway) and maybe a little more maintenance will control the corrosion just as effectively.

Thanks for all the input

 

[heaterman]

NO O2 barrier pipe is not really necessary. It is better to be sure, but there are other ways to deal with corrosion as well. Water treatment (which has to be done anyway) and maybe a little more maintenance will control the corrosion just as effectively.

I would agree if you changed the last part of your statement as follows.....

Water treatment and more maintenance will control the corrosion to some degree depending on the diligence of the owner and the budget for chemicals. (that would be more correct)

 

[DaveBP]

How long do Garn boilers last when they are maintained according to the manufacturer's water treatment procedures?

Might be a useful standard of comparison for a high quality welded steel boiler exposed to atmosphere and treated with a proper chemical program.

 

[intheknow]

This is an old thread, but I'm going to add two cents. I think that this is a better way to end this debate: (broken link removed to http://www.mrpexsystems.com/pdf/Diffusion.pdf)

 

[heaterman]

Ha! Now there's a blast from the past.

I wonder how Digger made out of what he wound up doing?

Must have lost track of this one way back when because I never answered DaveBP's question about the Garn.
We have seen them go up to 30 years if maintained. In fact we refurbed serial number 29 a couple years ago and it is in service yet as of this date.

I have seen them 10-12 years old and pitted so badly they look like they've been blasted with buckshot when the owner didn't take care of it.