End of Main Piping question

USA498

I have successfully re-piped my near boiler piping and the system runs quite well. Its about 8-10 min to fill the main. Thanks to all that guided me on this great site !

While looking at the end of the main just as it goes to the dry return I questioned the piping used. It looks like it would accumulate quite a bit of condensate in the Main before the first elbow.

I was thinking there should be a eccentric reducer somewhere in the mix so that the puddle does not form.  Any guidance would be appreciated.

Hap_Hazzard

I agree,

but eccentric reducers are really hard to find. You could just rotate the reducing elbow until the bottom is level or pitched downward. Make sure the rest of the dry return drops at least 1" per 20'. (You might want to check this with one of the pros, but I'm pretty sure that's right.)

Dave in QCA

eccentric reducer

I agree with Hap hazzard, if you turn the reducing el downward, you would eliminate the puddle.  I can't tell if your end of main, heading back to the boiler has enough fall that you can do that.

Regarding the eccentric reducers, I spent over a year lookin for eccentric reducing bushings and have concluded that no pipe manufacturer is currently manufacturing them.  However, eccentric bell reducers are being made by Anvil Pipe.  They are commonly used for fire sprinkler applications so you may have to go to a sprinkler or major pipe supplier to get one.  You won't find them in the plumbin shops.

USA498

A Dimension

Thanks for your replies Hap & Dave.

I am a little concerned that my A dimension will not be ideal if I pitch the current configuration of the main. I am currently at 28" for the A Dimension and will probably lose an inch when I pitch them.

 I was thinking about removing the two reducing elbows and installing 2 - 2" elbows and then an eccentric reducer which will drain the end and not have that much effect on the A Dimension.

While I was repiping the ends of the main I thought I would relocate the Main Vents here as well. The vents are currently piped at the end of the dry returns.

Dave in QCA

Looks like you have plenty...

In the photo, it looks like you have plenty of dimension A, but photos can be deceiving.  You are measuring to the water line, right?

USA498

dry return height

Dave, the bottom of the dry return is 28" from the center of the glass. I guess being that I don't run over a pound ( more like 1 to 2 oz ) I doubt it would be a problem going shorter than 28". Would you agree ?

Dave in QCA

reasonable

That seems like a reasonable assumption, however, I would be reluctant to drop more than an inch or 2.



On the other hand, the puddle is at the end of the distribution main, no supply steam going over that puddle, just condensate heading back to the boiler, and steam on its way to the main vent. So, it is not likely to impede steam getting to your radiators.  If it has not caused any water hammer, it might be best to leave well enough alone.

USA498

radiator take off

Dave, there is a radiator take off about 3 inches back from the end and I am pretty sure there is a big puddle. I have the same issue with the other main piped the same way. Both radiators/piping  have water hammer and don't heat very quickly compared to others on the main

Dave in QCA

Go for it!

In that case, I'd say its time to fix the problem!  I don't think an inch or 2 will hurt you on your B dimension.