In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Another Steam Boiler Sizing Concern
Sorry for my prior "non-post", but for some reason it worked. So here goes:
My relative is about to replace his 1930'ish oil fired steam boiler with a gas fired unit. He has had several quotes and both contractors have come in with 120/125,000 mbtu input units, one a Slant Fin and the other a Weill Mclain. As I figure the origial boiler was likely oversized, I asked him to compute his EDR to see whether the size quotes made sense. He did this and came up with 288 sq.ft. So if my math is correct:
288 x 240 = 69,120 x1.33 = 91,930 = DOE Heating Requirement
Based on this it appears that these two quotes make sense, especially given he has an inboard row home with his neighbors helping to heat both sidewalls. So while perhaps a "done deal", I"m not one adverse to making things more complicated. I've read on a number of threads about some gas powered boilers that achieve around 85% efficiency. So while I thought this may be an option, I soon learned that the smallest Slant Fin gas powered unit has an input of 154,000 mbtu and produces 408 sq.ft of steam. As I figure only around 300 sq.ft of steam is needed, I'm concerned that the larger unit may be oversized enough to reduce its efficiency to the point it is a "wash" with the smaller units in terms of actual gas/utility bill usage. So it wouldn't make sense to do this unless these powered gas burners can be throttled down enough to meet his application. This may be possible to some degree, but I don't know of any possible adverse effects in doing so. It also wouldn't make sense if the end usage results are close in that the powered burner appears more complex and is noisier. Also, in this case. a unit this large may require a larger gas meter or gas main to the house. That would not be an added cost in this case, but just add to the complexity of the job.
So I would appreciate any comments as to whether I'm seeing this right or am I way off base (a distinct possibility !). I would like to see him get this job done right because, as you know, most homeowners only have this opportunity once or twice in their lifetime.
Thanks For Listening !