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Pex al pex install

Kaizen

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I am well versed in crimp pex. I need to run a copper baseboard in a hard to access area so need to run return inside the baseboard. reading pex al pex is the best for this?
besides the tool that chamfers the inside of pex al pex are there any other tools I need? really don't want to have another tool around collecting dust if it can be avoided. not a lot of videos in English showing the installation. I see compression fittings and other fittings that use a tool but not sure what goes where.

can normal pex be used and insulated every few feet or something to keep it from rubbing?
 
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75gmck25

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I had to run PEX through holes I drilled in the iron main support beam in my basement and I just wrapped the PEX in short sections of reinforced rubber hose I bought at HD. The thick walled hose was big enough to slip over the outside of 3/4" PEX and still leave room for expansion and contraction.

If you are worried about damage to the pipe behind a baseboard it would be more durable if you use copper, or for really vulnerable areas you could even use iron pipe.

Bruce
 

skoronesa

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Jan 2, 2015
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If you're worried about rubbing/noise yes, you can just insulate it. Fostapex is different for two reasons, the aluminum layer as you know and that the inner has a sealed coating to stop the ingress of air into the water. They make pex without the aluminum that is sealed as well, the viega brand we get is black with a red stripe for heating and you wouldn't need the stripper tool. I don't know what brand of fittings you are getting that needs a chamfer on the inside, viega just needs the aluminum layer removed from fostapex on the outside and the inside is left untouched. Pretty sure uponor/wirsboro is the same. The aluminum layer helps a bit with heat loss but is mostly to stop mice/rats from chewing through it. It bends nice too.

Fyi, in case some one suggests it, YOU CAN NOT PROPRESS BASEBOARD COPPER TUBING. It is too thin to provide enough pressure against the oring and will just leak. If you use propress you would need to solder on a piece of L or M copper.
 
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Kaizen

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If you're worried about rubbing/noise yes, you can just insulate it. Fostapex is different for two reasons, the aluminum layer as you know and that the inner has a sealed coating to stop the ingress of air into the water. They make pex without the aluminum that is sealed as well, the viega brand we get is black with a red stripe for heating and you wouldn't need the stripper tool. I don't know what brand of fittings you are getting that needs a chamfer on the inside, viega just needs the aluminum layer removed from fostapex on the outside and the inside is left untouched. Pretty sure uponor/wirsboro is the same. The aluminum layer helps a bit with heat loss but is mostly to stop mice/rats from chewing through it. It bends nice too.

Fyi, in case some one suggests it, YOU CAN NOT PROPRESS BASEBOARD COPPER TUBING. It is too thin to provide enough pressure against the oring and will just leak. If you use propress you would need to solder on a piece of L or M copper.



I would solder in a pex connector between the copper.
I had read that straight pex expands at a different rate....much faster...then the copper so it makes a heck of a racket. Also read this expansion and contraction causes rubbing from the fins and eventual failure. It's just my house and would prefer to not use copper due to the cost.
I like the idea of wrapping it in rubber hose to insulate the heat and from damage

Thanks for the feedback everyone


Sent from my iPhone using Tapatalk
 
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brewchief

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If you use pex it needs to have an oxygen barrier, it can be pex-al-pex or regular pex designed for heating system use, do not use the standard plumbing pex as it will allow oxygen into your system and cause rust and corrosion on the ferrous metals.

How long of a run is it? If you have to buy a roll of pex and any tooling it might end up being pretty close to the same price to do it in copper, at least the section that returns above the fintube.
 
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Kaizen

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If you use pex it needs to have an oxygen barrier, it can be pex-al-pex or regular pex designed for heating system use, do not use the standard plumbing pex as it will allow oxygen into your system and cause rust and corrosion on the ferrous metals.

How long of a run is it? If you have to buy a roll of pex and any tooling it might end up being pretty close to the same price to do it in copper, at least the section that returns above the fintube.

right. oxy barrier. I already have all the fittings for either so just looking at the pipe. about 80 feet including the return. rooms all have carpet so figured it would save me some prep and damage over soldering and running the pipe between the baseboards.
I've never understood the oxygen barrier very well. doesn't it get picked up as air in the air eliminators?
 

Bondo

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If you use pex it needs to have an oxygen barrier, it can be pex-al-pex or regular pex designed for heating system use, do not use the standard plumbing pex as it will allow oxygen into your system and cause rust and corrosion on the ferrous metals.

How long of a run is it? If you have to buy a roll of pex and any tooling it might end up being pretty close to the same price to do it in copper, at least the section that returns above the fintube.

Ayuh,..... Agreed,.....

I've used alota pex in boiler systems, 'n no Special tools,....

Just a ratchet cutter to cut the tubin', ssteel crimp rings, 'n ratchin' crimper,....

I just blew a 1" line from my owboiler this mornin',....
Isolated the leak with valves, repressurized the system, 'n switched to oil, til Monday or Tuesday when the industrial places open, to get oxygen barrier pex,....
Found 1" pex at the box stores, but No O-barrier stuff,......:(

I've never understood the oxygen barrier very well. doesn't it get picked up as air in the air eliminators?

It blocks the migration of O2 molecules from passsin' Through the tubin' itself,...
Normally boiler water becomes sorta Dead water, no free oxygen, suffocates fish,.....
The barrier is also nearly of the molecular level,....
 
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Kaizen

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It blocks the migration of O2 molecules from passsin' Through the tubin' itself,...
Normally boiler water becomes sorta Dead water, no free oxygen, suffocates fish,.....
The barrier is also nearly of the molecular level,....

I get the barrier and the science of it. what I don't get is oxygen should form bubbles in the system right? just like an air bubble. why is it not just purged by the air burper thing?
 

Bondo

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I get the barrier and the science of it. what I don't get is oxygen should form bubbles in the system right? just like an air bubble. why is it not just purged by the air burper thing?

Nope, it ain't 'bout bubbles, it's 'bout o2 content in the water,....
 
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