Drop Header:Which way to Go?

vaporvac

In figuring out the best piping for the Slantfin tr50s we've come across a dilemna. We've emailed the techhelp there, but are seeking further imput.



The Tr50s have two tappings, one in front(3") and one in back(2"). The back one comes up and over forming a t juncture with the front tapping which then continues up and over into the drop header. All the drop headers I've seen go towards the rear of the boiler, but to hit my existing main flange perfectly, we would need to drop it forward. No need to worry about headroom as there's plenty of height available. Is there any reason not to do it this way? I prefer not to extend the mains. I'm attaching a little diagram showing it going forward with two alternate configurations.



Also, SF connects the drop directly into the mains, but everyone seems to do the regular drop-header into a supply header and then up into the mains. Any advantages to either method or am I just misunderstanding what the SF rep says.



Still recuperating from the tear-down. Just watching made me ache!

Danny Scully

Risers

The 2 risers need to connect independently into the header.

vaporvac

Piping Diagram

Thanks Danny,

That's what I thought, but after we were having a hard time figuring out how to tie the risers into the header I called Slantfin. I thought maybe I was misinterpreting their diagram. However, they said we should do it as shown, tying the back riser into the front at a tee juction and from there continue up and over to form the drop header (actually they suggest dropping directly into the mains. I'm attaching the piping diagram (see p. 4) as it might give you some more insight into my dilemma.

The other boiler (they're being stage-fired) drops into the same supply header.

Also, the diagram title says oil, but I'm using a gas conversion burner.

Rod

Dual Risers

Hi- I would disregard the drawings. I think what they are trying to accomplish is to alleviate the potential problem of a cockeyed waterline (See diagram on page 49 of "The Lost Art...." as the way it is piped in the drawing does nothing for the velocity. If you want to use the second exit port I'd pipe both risers in 3 inch and then use a bell reducer to reduce to the smaller exit port. As Danny mentioned each exit port needs its own individual riser to the header. Using two individual risers will slow the velocity and allow water to settle out of the steam.

- Rod

The Steam Whisperer (Formerly Boilerpro)

slantfin piping

Slantfin's diagrams do show a header with its own equalizer and then the steam supply comes off the top of the header.    

I also don't like the two boiler risers tying together in a tee before raching the header.  I haven't piped any mulitple boilers with 2 risers each, but my thought is to pipe each riser seperately into the common header.  The goal of the supply piping to the header is to keep the pressure drop across the piping at a minimum and the same for each boiler, so the boiler water lines remain equal.  To me, keeping the risers separate would better accomplish this goal.  Installing the boilers back to back with the header in the center of the boilers would keep this piping as short as possible....but probably a little tricky when firguring the venting.  You could offset the boilers enough for the venting to clear and still get the piping equal, but just slightly longer.  Gerry Gill has done multiple boilers with two reiser on each boiler.

SWEI

depending on the outlet spacing

you might be able to locate the header between the boiler risers.  Don't forget unions on the risers so you can pull a boiler if something comes up later.

Dave in QCA

Follow the Expert

Follow the advice of the Steam Whisperer. 

vaporvac

Clarification...

Thanks for clarifying that TSW. That's how I read it, but the SF techie insist it went directly into the mains. I think it may have been a case of calling things by different names. I call the bit between the risers the supply header, maybe he was calling it the mains, but meant supply header.

Anyway...

I love the idea of putting the boilers back to back and coming out the sides with the drop header. That's why this is such a great forum! Bingo! Fresh eyes! I'm posting pics of the empty space in case anyone has any further input. the dinesions of usable space are: 9' (from back wall to mains take-off) x 81/2' (from wet return to coal boiler) x 71/2' (floor to bottom of mains).

You can see the old vent hole in one of the pics.

I'm hoping Gerry Gill will pip in if he has the time and sees this post.

Hap_Hazzard

The point of the diagram

I think the point the diagram was trying to make is that the risers should go straight up at least 18" inches from the top of the boiler (24" above the water line) before they connect to anything. More is better. A long vertical riser will allow most of the water to fall out before it even reaches the header.



The worst thing about the diagram was that it gave the impression that you could tie the two risers together without swing-arms, which is a good way to make the sections leak.

nicholas bonham-carter

rusty return

I would try to flush that return out, if possible. a hose fitting could be adapted on to one end, and then flushed with hose pressure.

make sure there are no horizontals in it which are not well below the waterlines.--nbc

Dave in QCA

Great!

Great to see the pictures of the boiler room.  Can you take more? 

Also, I am wondering about 2 things.  What is the elevation above the floor, of the horizontal return piping located in the area below your return trap?   And, what are the return pipes that we see that drop and connect to that pipe?  Are they condensate returns on your 2-pipe?  Or, are they end of steam main drips?



I was just thinking about the earlier questions about wet/dry returns and the new boiler water line.

vaporvac

More Pics & Dimensions

Thank you all for the replies. NBC, I will flush those returns out and see what their actual state is then. They seem really heavy-duty so maybe we can add a flush-out to the existing piping. If not we'll probably redo in copper.



I'm adding a few more pics and a bit more explanation. There is just one single mains that wraps around the entire basement and through the garage exiting in the pictures on the right front. That drops down into that return line so I suppose it's the end of mains steam drip. The pipe just behind is the condensate return line. It ties into the Trane vent (which is the big black box that looks like something off a steam locomotive) in TWO places: directly into the box and just below it. There's not actually any venting on the mains with this system. Amazing that it works quite well.

The big cut off pipe is the part of the mains that tied into 1/2 of the boiler. We probably will cut that off after we determine the final piping.

One can see the water feed with the blue handle and tag near the ceiling. The other pipe to the left of the cut-off mains is an equalizer of sorts. I think it's the vacuum equalizer that I've read about and comes directly off the mains. You can see it the newer pic next to the coal boiler. There's always hammering in that line that I'll investigate later.



The old water level was 29.5, the new one is 25.5, but will be higher once we pour the pad. The wet return in 11.5" from the floor and 20" by the return trap. that actual inlet on the new boilers is 4.5" from the floor. Does that help, David?



I'm including pictures of the new boiler to give a sense of the piping dilemma. Could they have made it more difficult. The closed port on the top back is for the second riser. I'm sure the pros would have this figured out in no time. That's why they're called pros!



I have a bit of time to figure this out as I'm noticing the ceiling coming down and will probably deal with that first because that would be so much fun to do after the boilers are in!

Dave in QCA

water line will be fine

Thanks for the details.  I was beginning to worry about the water line, but your new water line will be fine, especially when you have the boilers setting on a concrete pad that will probably be about 4" thick.  The new water line will be about the same as the old and well above those horizontal return pipes.



I am surprised at how tiny those Slantfin boilers are!  They will run efficiently!

vaporvac

Same ? here...

I, too, wondered the same thing. Looking at the piping diagramodfm  it is aapparently for the oil application. For gas (which I am using), one needs to size the smaller  pipe up to a matching 3in. I'm not sure why that is the case, but it is.



I really wonder why the take-offs are placed where they are...one in front and one in back which explains their directions to bring the back riser into the front riser and from there go up and over into the supply header, as I showed in the initial drawing. This is what is shown in the install pdf and verified by the tech rep. I emailed him the sketch to re-verify, but haven't heard back. In order to have them enter the supply header independently, we have to rotate the boilers somehow, either back-to-back or facing.

I wish I could find at least one pic of a Slantfin install with the double risers. They're only used for the TR50s and above.

Paul48

Perception

      I don't read the diagram like that, at all. I see....Use 2 tappings for oil, and a single for gas. It would have been easy enough for them to have both drawings as side views, with the smaller riser increased in size then connected to the larger, for gas. If that was their intention.

     Their 2 riser diagram seems contrary to conventional wisdom for near-boiler piping. It sets up a collision of steam, similar to tapping between the risers.

      If it were me, I'd want to speak with someone in "Engineering" directly. Ask....It couldn't hurt.

gerry gill

sorry for the delay Vaporvac, been a busy year

As Paul48 says, i question the duel risers on the slantfin as they don't appear in their multiple boiler diagram. I would recommend also a call to slantfin tech support on that. Don't be bashful, as we in the field will call a companies tech support when necessary. Thats what it is there for. If all four risers are to be used you could pipe it like we did in this link,



http://www.gwgillplumbingandheating.com/webapp/p/216/multiple-boiler-install.html



By turning the boilers sideways as was previously suggested. In the pictures, looks are deceiving. Even tho one boiler is bigger, the important thing stayed the same, that being they both have the same water line height from the floor.

Steamhead

Take those plugs out

and run the second riser from each boiler up to a drop header. According to the diagram I have, a single steam riser is only acceptable on a 3- or 4-section boiler of this type. 5 sections or above require using both risers.



I'll try to attach the diagram.

vaporvac

Thought this Post was Dead!!!

Wow! I thought noone else was going to reply!!! Maybe it's a good thing the heating seasoning has come to an end and the cooling one isn't yet in full swing!



So, to reply to the postings. I did check with Larry Askew, the tech rep at SF. For gas, BOTH tappings are used with the TR50 and above. With the TR40 only one. (They were originally designed with only one tapping for all sizes, but they found this interfered with the water level and produced wet steam, so they changed the design.They don't have multiple broilers illustrated for both piping options, but they both ARE used with all the boilers TR50 and larger.)) So I need both of them and the second one does indeed need to be sized up to 3" as well. So for the TR50, it's 2 x 3" risers.



I've found their diagrams very confusing, to say the least. Larry had to send me a couple of diagrams extra that aren't on their website. Nothing comes with the actual boilers. Larry also verified that's how the two tie in together. I think it looks like a bad design, but who am I? In the schematic showing our proposed piping (see: http://www.heatinghelp.com/forum-thread/146319/TwinBoiler-Schematic _), we've NOT used this design.So far, I haven't seen anyone on this board do a Tr50 or above, only the TR40 which only uses one tapping.



Gerry, that is a beautiful install! Are those street Ls that you used? I had envisioned this set-up and may draw up another schematic, If you guys don't think the one in my most recent posting would work correctly. See: http://www.heatinghelp.com/forum-thread/146319/TwinBoiler-Schematic

It's a bit more space efficient for working on them in the future and fits in with the current mains a bit better. However, what ever you think. It could work with tweeking.

thanks for the replies...I was thinking I'd overstayed my welcome! Please check out the twinboiler scematic post.

Colleen

P.S. Steamhead. did you ever get my email for the Speakman Sentinel schematic?

gerry gill

not street el's

but could be..there are close nipples in between the 90's.

Steamhead

No I didn't.....

try again at steam dot head at verizon dot net .