HDPE vs. PVC (temp. sensitive)

[leblanc52]

anyone know the lowest "safe" operating temperature of PVC? in a Geothermal application, water handling temperatures can drop to around 30 degrees F. HDPE performs well under these temperatures, but for ease and speed of installation, especially in tight spaces where fusion is quite a hassle it would be beneficial to be able to use PVC.

i am very wary of the operating temperature of PVC, seeing as if a joint fails or pipe bursts, the GPM of some of my systems rises above 60 GPM and this would cause VERY expensive repairs to the home.

my pipe sizes are rather small, either 1 1/4" or 2"

what is PVC good to handle?
are there any other options to consider?

any help would be greatly appreciated, HDPE is time consuming vs. PVC, but the risk vs. reward is too much to warrant installing on a tangent without investigation!

 

[idratherbefishing]

Is the system an open or closed loop?

We use PVC all the time for this application, for the very reason that you have described with the problems of the fusion pipe work.

 

[leblanc52]

we do primarily closed loop systems, but do have one open loop on the go. closed loop systems would be more likely to have a lowered EWT over time, but not by much in my area.

how long have you been installing with PVC?

 

[raugeo]

Gentlemen,

PVC is not an accepted material by IGSPHA because it has been used and has failed. PVC can not handle the temperature swings for geothermal applications. I have worked with members for the IGSPHA Technical Committee within the past year and I know for a fact PVC is not an accepted material.

There are only two materials:

HDPE and PEXa

IGSHPA approved of PEXa on 10/02/08 and It is the evolution of geothermal pipe because no heat fusion is required, it has greater flexibility, is resistant to notches and gouges and if kinked you apply a heat gun because it is a thermoset plastic. Also the PROBALANCE XL manifold replaces the reverse return header because it is mounted in the home or facility or is mounted in a vault outside of the home or building. Therefore the system is accesible at all times. If you want to know more please do not hesitate to contact me.