copper equalizer

STEAM DOCTOR

Good morning. Is there any good reason not to use copper equalizers. If my understanding is correct there will be very little steam going into the equalizer. Assuming there is a proper Hartford loop when using dry returns or if there is a wet return, there is really no way to get air out of the equalizer. The steam could piggyback on the water going through the equalizer but in that event the steam would presumably turn to condensate very quickly. Please correct me if my understanding is wrong.

Brad White

Below the waterline, copper

is not a problem. Steamhead among others, uses copper below the waterline and that is good enough for me.

STEAM DOCTOR

Above water line

Thanks for the reply. I have no problem using copper below the water line. My question was about the equalizer part that is above the water line

Brad White

My bad!

I was obviously not paying attention. If it regularly sees steam, use iron pipe. No question.

EDIT: You will of course have steam in the equalizer, above the waterline, with the regularity of having steam anywhere in your system.

STEAM DOCTOR

copper

I guess my question really is does the equalizer really see steam. The equalizer is in essence an unvented pipe.

Paul Fredricks_3

temperature

The steam is not the issue, as much as temperature is. And while it may not see much steam at 212°, it will see water at 212°. For that reason it makes sense not put copper up there.

STEAM DOCTOR

temp

The below water line temps are also 212(at least in Hartford loop). Is there a reason to distinguish between the equalizer and the below water line piping?

STEAM DOCTOR

latent heat vs sensible heat

I am also wondering if the 212 steam, which has more latent heat the 212 water (which has same sensible heat),would affect the copper more then the water. The water and the steam are the same temp but the steam has more heat to give off to the copper.

Brad White

The temperature issue

is not just temperature itself but the stresses of rapid changes in temperature between steam cycles. That tends to work against solder joints. Copper and copper alloys also tend to "work-harden", become harder and more brittle as they are stressed.

Brad White

The sensible vs. latent heat issue

It is all the same temperature as you note. The difference is in the heat contained in the mass of steam (with an extra 970 or so BTUs per pound) on top of the sensible heat of the source water.

Rod

Copper Equalizer

As I understand it, with copper, the problem is that the expansion puts a lot of strain on the soldiered joints which may, over time, lead to failure. This would apply especially to an application (like a header piping ) where the piping configuration results in torsional forces on the joints. By the book you should stick to black iron, however like everything in life there are exceptions to the rules. I've noticed from pictures posted  that quite a lot of the pros use copper on the equalizer though in all cases they avoid torsional situations. Properly sweating large copper pipe needs experience so I'm inclined to think it's best for amateurs to stick with threaded black iron. Just my 2 cents.

- Rod

Charlie from wmass

I would be concerned also

with electrolysis as the equalizer piping is what gets wet first with the steam formation and will have time to go through many wet dry periods. I still only use iron both above and below the waterline. Thats the small pipe after all once you hit the equalizer so the threading is easy.

Paul Fredricks_3

Yeah

That makes sense. Thank Brad.

STEAM DOCTOR

thanks

Thanks to BW and Charlie for the great insight.Iron it is above water line. I'm assuming that below the water line you don't have the same issues do to the relative slow change in temp(due to the fact that the pipes are always filled with relatively hot water).

Brad White

That is correct-

While the above waterline piping and below waterline piping can and do share the same temperature ranges within a few degrees, the rate of change below the water side is relatively slow.



Above the waterline, going from room temperature to 215F in a few minutes -and back again to room temperature in minutes as well- is tough on copper. Below the waterline, you will never get much above 210F and it will take 15-20 minutes to go from room temperature to whatever peak you do get below the waterline. It likely will be cooler than 200F and once warm may get to room temperature some hours later.