Burnham replacement boiler EDR/Pick Up Question

Local1Plumber

Hey all, this past winter my residential boiler has finally had it. A crack in one of the sections has me heating the atmosphere lol. That said, contrary to what my knees want I will be replacing it this summer and am trying to appropriately size up my replacement. I own "The Lost Art of Steam Heat" for a while now and have been going over all the calculations. Essentially I have about 353 EDR (radiators/blind riser) no pick up factor added in. If I add a 1.33 pick up its roughly 470 EDR. If I multiply 470 X 240 (btu) I will need around 113,000 btu boiler. In regards to a Burnham I'm looking at a "STMX150". Am I missing anything? Again this is for my home so I'm not trying to get "free" advice for help pricing a job. An extra set of eyes is appreciated. Thanks for stopping in.

STMX150NRHPA.pdf

ChrisJ

That will work but if it was mine id go with the STMX125.

But personally id recommend a WM EG40 or a Peerless.

Steamhead

@Local1Plumber , the boiler's square feet rating has the pickup factor built in. If you're going to use a SteamMax the 150 is the right choice. But make sure your steam pipes are insulated and your main vents are properly sized.

Is this a one-pipe system?

Jamie Hall

You could just compare your EDR to the EDR rating of the boiler — no conversions needed, the pick up factor is already worked into the boiler rating…