Flex Pex?

[KRB64]

This is the first time I've ever used PEX thus I'm not aware of my options & limitations.

I have run 1" O2 barrier from the OWB to the house. Problem is the crawlspace. From the joists to bedrock is only abot 2' and that's where I'm hanging my pump. I'm concerned that the 1" won't make the turn from horizontal to vertical in that distance, not easily anyway.

Are there preformed 90* sweeps? I've seen the elbow joints, do they affect performance/flow? If not, which can be recommended?

Thanks

 

[Biker Dude]

There are no preformed long pex ells as far as I know but there are 90° bend supports which are metal and wrap around the pex.

As for short ells, I don't think they would restrict flow enough to matter unless your OWB is 200 ft. from the house or more.

 

[mtfallsmikey]

1" PEX is a be-otch to bend...use ells. If you REALLY want long sweeps, get 1" copper long radius ells, solder stubs in them, use Sharkbite fittings to join to PEX.

 

[i'mstihlaguy]

This is the first time I've ever used PEX thus I'm not aware of my options & limitations.

I have run 1" O2 barrier from the OWB to the house. Problem is the crawlspace. From the joists to bedrock is only abot 2' and that's where I'm hanging my pump. I'm concerned that the 1" won't make the turn from horizontal to vertical in that distance, not easily anyway.

Are there preformed 90* sweeps? I've seen the elbow joints, do they affect performance/flow? If not, which can be recommended?

Thanks

You can find PEX installation manuals on the web. One of them states the minimum bend radius is 6X the OD. Can you just locate the pump directly under the vertical run and use a 90 pipe fitting on the outlet to make the turn then convert back to PEX? If you are worried about flow, you could use two bronze 45's after the pump outlet then convert to PEX.

 

[Windwalker7]

I used 90* Shark Bites.

 

[KRB64]

There are no preformed long pex ells as far as I know but there are 90° bend supports which are metal and wrap around the pex.

As for short ells, I don't think they would restrict flow enough to matter unless your OWB is 200 ft. from the house or more.

Where can one get this contraption? BTW, its only 95' from the house.

Sounds like Sharkbites are the thing. Whether I use a 90* or a copper sweep. Are Sharkbites availble in pex X pex?

 

[stumpjumper83]

pex pipe

sharkbites are brass, seatech's are plastic. I'm not sure where they are getting their figgures on bending pex, but you should have about 16" to bend 1" pex at a 90. You can also use crimp fittings, the tool is expensive, but the fittings are cheaper than sharkbites or seatech.

Now as for what fits what. Pipe comes in two different sizing schemes. pvc is one size, and cpvc, copper, & pex are the other size. this means that you use sharkbites to connect cpvc to copper to pex in a three way connection. They seal off the outside of the pipe, so maye sure their are no burrs to damage the o-ring inside the fitting. This is especially important when connecting copper. Be sure to push the fitting completely together, and its pretty easy to work with. Fittings are re-useable. Its a joy compared to glue or solder.

If you have other question feel free to ask, I'm employed as a plumber right now...

 

[i'mstihlaguy]

Where can one get this contraption? BTW, its only 95' from the house.

Sounds like Sharkbites are the thing. Whether I use a 90* or a copper sweep. Are Sharkbites availble in pex X pex?

May not be the best price but this site shows some of the available fittings.
http://www.pexsupply.com/CategoryPre.asp?cID=588&brandid=

 

[KRB64]

Thanks. I was wondering if there were different applications or if they were all interchangable.

I was concerned that any joints would affect the efficiency. I'll look this weekend and see if I can make a 90* bend in about 16" or so.

 

[i'mstihlaguy]

Also, forgot to mention if you are using Aluma-pex, be aware that the fittings are different than for standard pex since the Aluma-pex has a larger diameter. You probably already knew this but its worth mentioning just in case you do decide to go that route.

 

[Labman]

In most piping, the rule of thumb is that each elbow adds as much restriction as 5 times the diameter. So an elbow in a 1'' line is like adding 5'' of pipe.

Shark-Bites are expensive, but slick.

 

[KRB64]

Ah, see, this is the stuff I'm unaware of and why this site is so handy!

My PEX looks llike it has an aluminum layer but it is called Ipex Kitec pex. Doesn't say anything about aluminium...?

I figured an elbow made a difference, just didn't know how to quantify. This will be at the pump so shouldn't have an effect if it only adds 5" to the equation.

Thanks for all the options & insight guys!

 

[mtfallsmikey]

No answer here but if you don't get any, go to heatinghelp.com, post your question on the Wall...lotsa guys there use Kitec.

 

[i'mstihlaguy]

Kitec and PEX-AL-PEX are the same basic design and have a larger diameter and better flow rates than regular pex. For example, 1" PEX-AL-PEX gives you 5.2 GPM at 2 ft/sec and 1" PEX gives you 3.8 GPM at 2 ft/sec. And the great thing about having the aluminum layer is that it doesn't change length nearly as bad with temp. changes.

I am actually using Kitec compression fittings on my PEX-AL-PEX.

I too am suprised that an elbow would be equivalent to a 5" length of pipe.

 

[i'mstihlaguy]

Even better, here's an installation guide for Kitec.

 

[KRB64]

Hey thanks man. Should have known there was a manual somewhere for the stuff. I'll give it a good read and get back.

 

[KRB64]

Also, forgot to mention if you are using Aluma-pex, be aware that the fittings are different than for standard pex since the Aluma-pex has a larger diameter. You probably already knew this but its worth mentioning just in case you do decide to go that route.

Well I know now. So far, I've been getting all my stuff from the guy I got the furnace from. Hadn't asked him about the transition or 90* tight turn, he's about 3 hrs away but will ship little pieces.

It is the PEX-AL-PEX so that means the special fittings, no Sharkbites.

But the manual does say I can bend that tight by hand like ya'll said so I'll give that a shot.

Say i'mstihlaguy, how's your install coming?

 

[i'mstihlaguy]

The boiler came in last weekend and I have it and all the parts but just can't get anything done between working daylight to dark and all the bad weather. I wish it would either quit raining or just freeze up. I hate to mud the underground lines in.

 

[Khtsr44]

Bending pex

You can make it easier to bend and handle if you warm it with a hairdryer, just don't over do it.

 

[KRB64]

You can make it easier to bend and handle if you warm it with a hairdryer, just don't over do it.

Thats a good tip, thanks, especially since it's 7* out there right now!