BTU'S of piping after boiler to rads & cellar and 2 floors need to be added to sizing of boiler?

baerlisnice

I 'am wondering in sizing new boiler that piping other then near boiler need to be added to the sq. ft and or BTU's , there is a lot of steam pipe in the cellar and up in 2 floors of 3,200 sq. ft. residence , approximately 80% is insulated. thank you in advance for everyone's help in this.

KC_Jones

No it does not. The rating on the boiler already has 33% pick up factor in it. Get the radiator EDR then compare that directly to the boiler manufacturers rating.

baerlisnice

thank you so much for writing, the EDR is 536, i used the Burnham guide the Mega steam 513 is 513 sq.ft production , and the Megasteam 629 is that output in steam , so which one should I use?

BobC

Your 536 EDR is only 5% larger than the 513 and given there is a 33% pickup factor I's go with the Megasteam 513. Near boiler piping is critical. make sure both steam outlets are used and I'd want a dropped header (oversized to keep the steam velocity low) as well.

Bob

baerlisnice

thank you so much for writing, i'am trying to do the best possible job to get some one in here but every contractor tells me a different set up thank you for the comment on the 513, I thought the 629 would be better because 2 contractors told me you need 20% more sq. ft. to accommodate all the piping in the basement and 50 % more if they are uninsulated !!!!!

KC_Jones

baerlisnice said:

thank you so much for writing, i'am trying to do the best possible job to get some one in here but every contractor tells me a different set up thank you for the comment on the 513, I thought the 629 would be better because 2 contractors told me you need 20% more sq. ft. to accommodate all the piping in the basement and 50 % more if they are uninsulated !!!!!

They are factually incorrect. If they add 20%, that would be in addition to the 33% the manufacturer has already.

Here are the numbers, for your education and so you have a rebuttal for their crazy suggestions.

Using the numbers from Burnham
The 513 fires at 1.35 Gallons per hour
Gross BTU input is 190,698 BTU
Efficiency is 86% so a gross output of 190,698x.86=164,000 BTU
Your system has 536 EDR x 240 BTU/sqft = 128,640 BTU

164,000-128,640 = 35,360 BTU for pickup or 27% pickup factor

That is enough excess to heat approximately 235 feet of un-insulated 2" pipe, that's a lot of pipe and I doubt very seriously if you have that much.

They want to add 20-50% on top of that, for what? I bet they can't tell you.