CPVC pipe is an option?

[MrEd]

Hi all.

On another thread, someone mentioned they were using CPVC pipe as part of their heating system piping. Until now I was deciding between 2 runs of 1" pex, or a single run of back iron pipe 1 1/4 from the tarm to the oil and back. I didn't realize CPVC would even work in a heating system. Is it a valid option? I've used PVC piping plenty and like the inexpensive quality, and the ease of working with it with tools I already own.

Any reason not to use it? I assume it is considered oxygen barrier?

 

[markpee]

Ed -

I found this on a CPVC industry website:

USES/APPLICATIONS
CPVC piping which is suitable for hot and cold water distribution has a 400 psi pressure rating at room temperature, and a 100 psi pressure rating at 180 F.

CPVC materials are resistant to many everyday household chemicals.

It looks like it would do the trick - now you have me thinking. I'm going to try to get pricing today, if you do the same, please let me know. I do believe however, that most pex has ratings up to 200 F - and I didn't see this on the site, though I could be wrong. As of now, I'm going to use 1 1/4" black iron, unless this CPVC thing will work.

 

[markpee]

As a follow up, I also not this:

The model codes recognize CPVC's capability to handle short-term pressure/temperature excursions beyond these levels. Therefore, CPVC is well suited for usage as T/P relief valve discharge lines, evidenced by its faultless service history over the past two decades in this application.

However, the site keeps referring to its use as a water supply pipe, I've found nothing related to hydronic system use.

 

[MrEd]

I got a price yesterday of $105 for a 21 foot section of 1 1/4 black iron...$5/foot. I also know that holding up a 21 foot section of black iron pipe is going to be a back-breaker if I could even figure out how to get it into the cellar.

Looks like PEX for me if the CPVC thing isn't an option.

 

[mysticfalcon]

CPVC does not however have an Oxygen Barrier.

 

[markpee]

I checked Lowes the other day, and they have 1 1/4" black iron at $1.79/foot in 10' lenghts - I have not checked the plumbing supply house yet - I'm a little surprised at the price you got. I hope it's not right.

 

[markpee]

I did find one more thing about CPVC, and it seems to agree that there is no oxygen barrier and some say it should not be used in a heating system. Sorry to hog the post, I should let some of the experts chime in.

 

[MrEd]

That price is accurate, but its from a small local supplier - they don't sell a lot of it so they probably pay a premium for it in small loads when you factor in trucking.

 

[MrEd]

Well without an O2 barrier, that kinda rules that out - guess it will be PEX.

Not to hijack my own thread, but every time I look at Pex and pex tools and pex fittings I get confused by all the different brands, styles etc. Is everything interchangeable (tools and fittings)?, or do you need to decide ahead of time which style and then commit to it (i.e. VHS or beta). If so, can someone just point me to exactly the brand fittings and tools that are compatible and best? I would want 1/2, 3/4 and 1" capability and readily available fittings pipe etc.

 

[WoodNotOil]

I used CPVC on the open tank side of my piping for cost reasons. I was told by someone else that after 3 years they started to have problems with theirs cracking near the joints. So it is not ideal for heating systems, even though the temp rating is good.

PEX is the better choice to keep cost down. I think most PEX is rated at 180* max, however maybe there are newer products now with a higher rating. As for fittings and tools, most of them are somewhat interchangeable. I used PEX on the boiler side of my storage tank and had only a few connections to make. I bought the pocket crimper http://www.pexcrimper.com/ and it did the job with no leaks. Much more affordable than the bigger commercial tools meant for real installers that do a lot of this. I used the inexpensive crimp fittings with rings like these http://www.pexsupply.com/CategoryPre.asp?cID=543&brandid;=.

If you want to be able to run your system at higher temps though, you may consider the long life of the iron and copper a good investment for the flexibility. That is up to you.

 

[leaddog]

years ago I used cpvc on a boiler (OWB type.) with a 100ft run. I had a over heat problem and the 3/4 in got about 6in dia. Also over time it swelled slightly over size so in a repair or change fittings wouldn't quite fit. It also got brittle. I would go with pex.
leaddog

 

[chuck172]

In my house, and I plan to stay for a while, I bit the bullet and stayed with copper. I really don't like change.

 

[BrownianHeatingTech]

Well without an O2 barrier, that kinda rules that out - guess it will be PEX.

Not to hijack my own thread, but every time I look at Pex and pex tools and pex fittings I get confused by all the different brands, styles etc. Is everything interchangeable (tools and fittings)?, or do you need to decide ahead of time which style and then commit to it (i.e. VHS or beta). If so, can someone just point me to exactly the brand fittings and tools that are compatible and best? I would want 1/2, 3/4 and 1" capability and readily available fittings pipe etc.

Fitting systems...

Cold-expansion fitting systems (Wirsbo, Rehau) are only compatible with pex-a pipe.

Compression fitting systems (almost everything else) are compatible with pex-a and pex-al-pex pipes. However, they tend to be more restrictive, since the internal port of the fitting is smaller.

The most cost-effective system is probably the Watts compression system.

The best (in my opinion) is the Rehau system, but it is also pretty much the most expensive.

Many supply houses have tools for rent.

As far as the pipe, pex-a is a standard, so any pex-a pipe has to meet certain minimums. Some brands tend to exceed the minimum standards. Personally, I use Uponor and Rehau pretty much exclusively.

Joe

 

[pybyr]

In my house, and I plan to stay for a while, I bit the bullet and stayed with copper. I really don't like change.

A long time ago, I was that way, then around 1999, a friend in the building trades gave me a scrap of Wirsbo pex to play around with. I did everything I could think of to mistreat that piece of PEX (hammer, vise, heat, etc., stretching it to far greater diameter than it was supposed to be stretched), and was bowled-over [completely contrary to my expectations] at its durability.

I plan to stay in my house until I go out feet-first, and I hope and reasonably expect that won't be for several decades-- and I now tend to use the PEX instead of copper for a lot of applications

 

[deerefanatic]

When I replumbed my house, I used PVC to get me from the well, to the water filter, down to the softner, then back up to my T that branched to the hot water heaters and cold water circuits........ From there, it's pex to the heaters, and copper ALL the way from there...... For cold, it's copper to the kitchen sink, then pex down to the other end of the house where it's connected to copper for everything else........

I LOVE the ease and trouble-free properties of Pex..... BUT, if I had the money, I'd use ALL copper in my plumbing..... PVC IMHO is ONLY suitable for cold water due to the fact that most plastics (PVC especially) give off nasty carcinogens when it gets hot......

 

[markpee]

To me there is no other choice than Viega Fostapex - it has great fittings, and a crimping system that ensures there will be no leaks. It is manufactured in Germany - need I say more. Their aluminum jacked pipe is awesome, and their 1" pex has a 1.032 ID. Check it out before you buy.

 

[pybyr]

To me there is no other choice than Viega Fostapex - it has great fittings, and a crimping system that ensures there will be no leaks. It is manufactured in Germany - need I say more. Their aluminum jacked pipe is awesome, and their 1" pex has a 1.032 ID. Check it out before you buy.

Viega looks like good stuff, but I think the same can be said for any of the quality makes of PEX, although each of the fittings and systems have their individual pros and cons- it's a Chevy vs Ford vs Dodge vs Toyota pickup thing- you like what you know, or what you bought.

I use Wirsbo/Uponor, probably because that's what I first got hold of and got used to, was able to borrow a tool from a friendly acuaintance pro, and then was able to buy a used but good Wirsbo expander tool at a really low price from another local pro who was getting out of the business. It's Swedish, and they're no less methodical than the Germans.... I like the Wirsbo system because it is easy to cut the PEX and collar rings off of fittings if you need to re-do/re- use, and I have never had, nor seen or heard of a leak, but I can see how some of the other makes' crimp-in-place systems might be easier to install in some (but not all) places or situations.

In any event, after many, many years of thinking that any and all plastic piping was always a cheesy second to copper, I now basically view copper as something that has certain continued limited advantages, but for most purposes/locations/tasks, I think you can't beat PEX. I tend to view PVC as something that has a good mix of price/weight/structural advantages in large diameters, but have no desire to drink anything that flows through it, nor to trust it with any combination of heat and pressure.

 

[sfriedri]

To me there is no other choice than Viega Fostapex - it has great fittings, and a crimping system that ensures there will be no leaks. It is manufactured in Germany - need I say more. Their aluminum jacked pipe is awesome, and their 1" pex has a 1.032 ID. Check it out before you buy.

I just checked Viega's website and their spec sheet for FostaPEX (http://www.viega-na.com/downloads/1201645046TD-PFFP-0907 FostaPEX.pdf) indicates an ID of 0.863" for their 1" tubing. The pressure drop they list in the table for 1" also lines up with what I have seen for other 1" PEX. Where did you see 1.032" listed as the ID? If you installed this did you confirm the actual ID?

Thanks