Proper Near Boiler Steam Piping

Steve Garson

I expect to receive my bids for a new steam boiler in the next week. I want to be sure that the piping quoted is correct.

I looked at the Weil McLain installation manual for the SGO-4. This boiler has only one riser, but my present system has two mains fed by two risers. I assume that how this is piped is very important, so I need advise on how to judge that the proposals do the job properly. The instructions do not address this.

Thanks!

Steve in Boston

Unknown

The contractors will need to

pipe the 2 system mains into the boiler main separately . This is a Peerless we installed last year with 2 system mains . The drop in the header is not a necessity but in my opinion it separates carryover water from the steam better than not having it at all . I would recommend going one size bigger on the boiler main than what Weil says is their minimum . It's money well spent to assure the system will see dry steam . Good luck with the repipe .

bernie_2

nera boiler piping

Near boiler piping on any system but particularly steam systems is possibly one of the most important and overlooked steps leading to many possible issues with the system.

Steve Garson

So the riser doesn't need to be piped between the two mains. It looks like your photo shows the riser connected to one size of a header with the two mains.

Steve Garson

So the riser doesn't need to be piped between the two mains. It looks like your photo shows the riser connected to one size of a header with the two mains.

Unknown

Nope

You want the 2 system mains in the flow of the steam path , so that any carryover water will go right to the return of the boiler . Having the boiler riser tee into the 2 system mains on each side of it is a big no-no .

I'm guessing that's how your system is piped now ? Would you be able to post a pic of the boiler here ?

Steve Garson

Ron:

Here is the present piping, which will have a single feed on the new boiler.

michael_15

I had thought

that if you took off the two risers from the boiler like such without combining them into a single header before they go off to the radiators, you might have problems.

Just thinking about it, what if one main has more radiators (and more venting) than the other? You might get steam preferentially moving into one main, which, among other problems, might lead to an uneven waterline in your boiler.

-Michael