New main drip and moving a vent

Polycarp

Thanks so much for all the great input I've gotten from this site. It's been invaluable.



I'm about to take my next step in my ongoing rehab of my one-pipe steam system. I was hoping the pros and pro-ish homeowners could take a look at the plan and let me know if I'm missing something.



My end of main drip line is clogged and needs to be replaced. (I want to eventually replace the whole wet return, but can only afford to do it in stages.) Since I'm taking this drip out and will have access to the end of the main, I also want to take the opportunity to:



1) move my vents from their current location (currently sharing a boiler runout, the best I could do at the time) to the end of the main and



2) add a mud leg to the end of the main (the pipes are 100 years old and all that scale and sludge is what did my drip line in, and I imagine this will continue to be a problem so I'd like to avoid that problem in the future) and



3) as per Steamhead's advice, increase the drip from 3/4" to 1".



I've attached a picture of my current vent location and a sketch of my plan. You can see that the main takes a 90 degree turn to feed the last riser runout and meet the wet return. Until I'm able to replace the rest of the wet return, I'm stuck with a 1" to 3/4" coupling to the horizontal wet return. This is another reason for the mud leg, I can just see this reducing coupling getting clogged.



And one last question: does antler or menorah configuration make any difference for venting? Antler made the most sense for the old vent location, but I have the opportunity to change it if I should.



So, anything wrong with my plan? Thanks in advance.

TomM

hey! looks like my basement!

regarding the mud leg, wouldn't a ball valve with plug be easier for maintenance than a cap? 

-

you could also put a garden hose attachment somewhere at the beginning of your wet return so you can flush the wet return annually. 

jpf321

what vents?

what vents do you plan on using ..



i concur on the ball valve idea .. at the very least, how about a union at the top of the mud leg so you can break it easier in the future.



nice sketching by the way.

Polycarp

ball valve

regarding the mud leg, wouldn't a ball valve with plug be easier for maintenance than a cap? 



Very likely.  But hose full port ball valves can be pretty spendy, so I'll have to balance it out.



you could also put a garden hose attachment somewhere at the beginning

of your wet return so you can flush the wet return annually. 









That's a good idea.  For it to work, I'd need an isolating valve for the main so i don't just wash stuff into the boiler though.

Polycarp

Vents and union

That's a great idea, a union would be much cheaper than a 1.5" valve.



I already have the vents (hopefully you can see them in the pic).  There are two Hoffman 75s.  I used your sizing sheet to spec 2 Gorton #1's.  Since the Hoffmans are a little bigger than the G1s and locally available, I decided to go with them instead.

Charlie from wmass

A coupling and a brass plug

would be more likely to come apart after a few years of service than an iron union. I would vote for a full port 1" ball valve on the mud leg. You can get 3/4" full port boiler drains too. in a straight pattern. One time busting knuckles to get that cap off would get me to go buy a ball valve.

Polycarp

ball valve

Maybe I'll just make that mud leg 3/4" and extra long and put the ball valve at the end.  I'd probably keep the Tee in the main at full size and reduce it with a coupling below just to capture as much gunk as possible.



A mud leg near the end of main seems like such a useful thing to me, especially for an older system, I wonder why I haven't seen (or at least noticed) it more often.

Polycarp

new plan

OK, based on everyone's input, here is the new plan.



I decided not to put the hose connection in here because while it is the end of the main, it is not the end of the wet return. When I replace the wet return, I'll put it in then.



But I still have my basic question about whether either an antler or Menorah configuration is better for the vents. I'm inclined toward the menorah just because it won't put torque on the union. But are there other concerns?





Thanks again everyone!

Rod

Question for Charlie

Hi- I'm just wondering if there is a possibility of the mud leg causing the steam to collapse at this point. (water hammer)  It would initially  fill with condensate (water) and would remain colder than the condensate and steam coming down the main. Thoughts?



Polycarp - Nice drawing! What did you use to do this?



- Rod

Polycarp

The drawings

are just freehand pen in my sketchbook with a little clean-up after I scan them.