Pex or PVC ?

[Reed Wells]

I am getting ready to start spending money ( ouch ) for a new outdoor wood furnace. Can anyone tell me the difference in pex and pvc? I have the black pvc? running below the frost line to the shop, and have had no problems with it in several years. Insulating it would be no problem, so I am thinking there has to be a reason for spending 20 bucks a ft. for pex, compared to 3 bucks a ft., for the black stuff. Any ideas guys. Does the black stuff not react well with hot water? Thanks, Reed

[Jay Jolliffe]

I don't have a wood furnace but a few are in the area where I live. I think the $20.00/ft is a 4" insulated flexible pipe with the 1" pex feed & return to the furnace. I could be wrong. Around here that's what their using. Also there were two people that made up their own feed & return by putting the pex in 4" pvc then insulated with a few layers of blue board insulation before they back filled the trench. They say it work's just the same as the already made up stuff.

[Greg Peterson]

What purpose does the tubing serve? From your post I'm not sure what you intend to use the line for.

[David G Baker]

Greg,
The tubing/pipe is used to circulate hot water or an antifreeze type solution from the outside boiler to the house radiators or forced air circulation system.
They are quite popular in areas that only have propane for heating the homes and in areas that have a plentiful supply of fire wood available.

[Joe Mioux]

Pex will last a lot longer.

Black PVC pipe? are you talking about Black Poly pipe that comes in rolls? If so that stuff won't survive long term especially with fittings such as t's y's l's etc.

I use miles of black poly pipe for irrigation.

I also have about 40 miles of somesort of black rubber tubing for my heating system in the greenhouses. After 23 years, in the old section, I am getting some failure.

In one of my stores we used PEX in concrete. works great and will continue to work great long after I am gone.

joe

[Don Abele]

Reed, by black PVC do you mean ABS? This looks just like PVC, though it is slightly thinner in the walls and black in color.

If that's the case, it's good from -40*F to 180*F and can be direct buried.

Not sure if that applies to your project as I am completely unfamiliar with what you are trying to do.

Be well,

Doc

[Greg Peterson]

Greg,
The tubing/pipe is used to circulate hot water or an antifreeze type solution from the outside boiler to the house radiators or forced air circulation system.


Thanks David. I thought might be what he was referring to, but wanted to be sure.

PEX can be direct buried, and works great for radiant heating. It's very easy to work with, which makes install go quick. Easy to undo if you need to rearrange, augment or alter.

The BORGs sell red and blue for color coding purposes. Red = hot, Blue = cold. Same stuff.

If you can get Wirsbo, that's the way to go. The PEX stocked by the BORG's uses a compression band to seal the connection. Wirsbo uses fittings whose OD is slightly larger than the ID of the tube, plus there is a half inch band of PEX that goes over the end of the tube. After expanding the Wirsbo with the expansion tool, slip the fitting into the tube, wait a few seconds, and move onto the next fitting. Wirsbo PEX has a memory and between the tubing and the reinforcement PEX ring, that connection is permanent.

The only thing to be mindful with PEX is direct sunlight will break down the poly.

[Jay Jolliffe]

If you don't insulate the pex there will be heat loss from the boiler to the house. The insulated pipe they sell with the stove can be laid on top of the ground. Central boiler is a big seller where I am & they sell the insulated pipe for the furnace.

[Reed Wells]

Don, you are right, It is black ABS. I will have to check with the furnace people on the temp. that the water gets as it leaves the furnace. I just thought if I could save a little over a thousand dollars on piping, by the end of summer I will be able to afford 10 cords of maple ($800.00) and hopefully a tank of gas for the pick-up.