3" Riser Vs 2" Riser

Lumberguy

Hello all,
I have a 1 pipe steam system that has 2- 2" mains (1 feeds the (5) radiators on the front of the house and the other feeds (5) radiators in the back of the house) and I'm having a New Burnham IN6I Steam Boiler being installed. The boiler has 2 ports which have 2" tapings. Using both 2" ports with a 2" riser that are 30" tall into a drop header. See attached pictures. The radiator calculations worked out to be 416 sq. ft. and the IN6I is rated for 450 Sg Ft. Had a knowledgeable old time steam guy I know take a look at the work and he said the risers are undersized and should be 3". What are the opinions of this fine group of knowledgeable steam people? Should the riser be 3"?

EdTheHeaterMan

In looking at the Installation manual, You can install the Burnham IN6I using only one of the boiler supply tappings. Using 2 tappings is optional and your contractor has decided to use both (a better choice). IIn the manual on page 17 is a piping diagram indicating the recommended pipe size of 2" for your Burnham IN6I. I believe that you are just fine. To the trained eye, one might consider the Pipe (B) in the diagram below should be 3", but it is not necessary according to the manufacturer.

3" would be necessary if you have a Burnham IN7I or larger

STEVEusaPA

Your flue piping is really bad-against code, and potentially dangerous.
For starters, water heater needs a riser before the elbow. And because it has a vent hood it needs to be higher than the barometric damper, which is the wrong one for gas, and installed wrong.

JUGHNE

Aren't the boiler outlets only 2" for all sizes of this line?

EBEBRATT-Ed

@Lumberguy

Your piping is fine. You have already gone over and above using 2 risers and a drop header. No issues.

As far as the flue piping goes. Coming off the water heater you need to make a vertical rise as high as possible (it's called self venting) then turn and go into the flue as high as possible.

Is there something else connected in the back? looks like 2 flue pipes going in the flue. I would double check on that could be an issue. The barometric if you use one has to be double acting for gas with spill switches wire in

EdTheHeaterMan

STEVEusaPA said:

Your flue piping is really bad-against code, and potentially dangerous.
For starters, water heater needs a riser before the elbow. And because it has a vent hood it needs to be higher than the barometric damper, which is the wrong one for gas, and installed wrong.

Steve, I think the barometric is from the old boiler. Probably replacing the old oil for a new gas boiler. I think the vent piping is not finished yet (or not even started). But good eye on the incorrect water heater vent design. It would be nice for the installer to correct that while venting the new boiler.

Lumberguy

Thank you all for your quick response. It's good to see there is consensus that the 2" piping is fine. Good eye @STEVEusaPA and as @EdTheHeaterMan has mentioned the venting has not been started. There is a second boiler which is Forced Hot water (gas) that heats another part of the house (used to be a cold storage room back in in the 1800's, now converted into a bath, Pantry room and Laundry room, house was built in 1790, the main box of the house is heated with steam). The Forced hot water boiler is the flue you see in the picture in the back that @EdTheHeaterMan has mentioned. Appreciate the feed back, those issues on venting will be addressed. We are hoping to take 1 section out of the main vent stack and move all other vents up, and create a vertical rise for the water heater's vent. @JUGHNE you are correct all lines are 2" except for the return lines which are 1" that tie into the Hartford loop which is pipe in 1-1/2". Thanks again for all the great feedback!!

ChrisJ

I've never seen anyone that neat and clean with thread sealer before?

Was there dope used on those threads?

Lumberguy

@ChrisJ you need pipe dope on the threads It all dry fitted, all the pipes need to be disassembled and then assembled with Teflon tape and Rector seal pipe thread compound (Tru Blue).

Lumberguy

Another question for the group. Is there a recommended measurement for the distance the Drop header, drops down from the riser? Currently the bottom of the drop header is about 12" above the top of the boiler. Is there a recommended distance the drop header should be above the water line as there is for the riser.

ChrisJ

Lumberguy said:

@ChrisJ you need pipe dope on the threads It all dry fitted, all the pipes need to be disassembled and then assembled with Teflon tape and Rector seal pipe thread compound (Tru Blue).

I wasn't sure if it was dry fitted, or, if someone was actually that picky.
When I do exposed piping in the livingspace I can make it look like that, but it takes a lot of time.

If that was my boiler, I'd want a 3" header on it, but the risers are fine. As has already been said, you can't go bigger.

JUGHNE

The height of the boiler risers above the water line is recommended by the I&O book, looks to be 24" for yours. You have plenty more than that which IMO is good.

The dropped horizontal header could be as low as you want, (just so you can get the top cover off of the boiler for cleaning).

The lower it is then the taller the steam main risers are, again good as it lets more water fall down into the header. All this is to give you dry steam.

EBEBRATT-Ed

@Lumberguy

You just have to keep the drop header above the boiler water line. I wouldn't go lower than the top of the boiler jacket

Lumberguy

Understood, Thanks guys!!

KC_Jones

Why have a second boiler for the hot water system?  If it’s that small of an area any water boiler you install will be massively oversized.  Seems like a hot water loop off the steam boiler would have made a lot more sense, I’m guessing that ship has already set sail.

EdTheHeaterMan

KC_Jones said:

Why have a second boiler for the hot water system?  If it’s that small of an area any water boiler you install will be massively oversized.  Seems like a hot water loop off the steam boiler would have made a lot more sense, I’m guessing that ship has already set sail.

I don't know KC, Lumber guy's converted cold storage room may be bigger than you think. He may have a lot of laundry, have a big appetite, and likes a spacious bathroom. That's why he needs a separate boiler for that huge space.

Just Say'in

Lumberguy

I wish I found this site back 20 yrs when I purchased the house, I thought is was odd have 2 boilers, but that's how the house was set up. Knowing what I know now, I would have asked the forum their thoughts, but I had to replace the steam boiler 15 years ago and dragged my feet till this year. Attached are a few photos of the old boiler. The second boiler (FHW) is heating an area about 350 Sq. Ft with little to no insulation in the walls.

EBEBRATT-Ed

back when a boiler was a boiler

BobC

Just thinking of moving that old beast makes my back hurt.

Bob

ChrisJ

EBEBRATT-Ed said:

back when a boiler was a boiler

I mean any modern steam boiler is a boiler.

Every single "hot water boiler" ever made on the other hand...........