pex vs. copper for an indoor boiler

[Bob Rohr]

I used per for the 1st time for baseboard heat in my addition. I did notice the ID of a 3/4 pex fitting was about the same size as 1/2 copper. That's gotta hurt flow alot. Pex was easy to work with wish I spent the extra money on the copper. My boiler will creep up to 205 if it idles for awhile. I hope it's never an issue if that zone calls while the Temps are higher than normal

Determine what type of flow rates you need copper and pex tube have different ID. Not a lot of selection in 1-1/4 pex fittings as far as tees and adapters. Copper in sizes 1-1/4 and larger may pencil out less $$.

If you do go with large diameter pex, buy the straight 20 foot sticks

 

[Highbeam]

If you do go with large diameter pex, buy the straight 20 foot sticks

This is so true. I fought a coil of 3/4" in domestic plumbing and won't do that again. Way too stiff.

 

[krinkov]

i used copper on my install in 1986 for the essex boiler now use the same copper pipe on the 140 woodgun in 2015.i use copper on everything then you are finished.

 

[maple1]

I have found though that you need to be careful with copper on DHW lines, particularly ones that hook up to a boiler coil. I had one spring a leak a few years ago, it was wasted away to not much, and when my father made changes on his a few years ago his were pretty well toasted too. Not sure if it's a chemistry thing, or a velocity thing, or a combination.

 

[Pat32rf]

Copper is supposed to be the NOBLE metal but has proved to dissolve under the right conditions. This is why we now have to install coated oil lines to our furnace or water heaters in Ontario. In our area we have acid water and when we remove copper domestic water lines that have been in service for 30 years they are very eroded on the inside. When I have a wall open I replace them.....
Some years ago I used to service electric water heaters and boilers. One sausage maker insisted on very pure water for his steam cooker. I had to replace his regular copper elements every year as they dissolved in the pure water. Don't know where the dissolved copper wound up.....

 

[Highbeam]

Copper is supposed to be the NOBLE metal but has proved to dissolve under the right conditions. This is why we now have to install coated oil lines to our furnace or water heaters in Ontario. In our area we have acid water and when we remove copper domestic water lines that have been in service for 30 years they are very eroded on the inside. When I have a wall open I replace them.....
Some years ago I used to service electric water heaters and boilers. One sausage maker insisted on very pure water for his steam cooker. I had to replace his regular copper elements every year as they dissolved in the pure water. Don't know where the dissolved copper wound up.....

That dissolved copper stays in the water all the way through the sewage treatment process. I get called in to fix the water system when discharges from the sewage treatment plant contain too much dissolved copper. Never mind the compromised plumbing systems.

 

[Pat32rf]

There used to be a geothermal system in our area (Ontario) where they would bury the copper freon coils directly in the ground instead of running antifreeze and another heart exchanger. You only needed a short run of copper instead of hundreds of feet of PVC.....From what the old timers say, the copper started to leak in about 15-20 years and needed to be replaced as it was paper thin.