Steam and Hydronic system not working well

Michael G.

Size of boiler

So my Dunkirk PVSB-8D has the following ratings:

262,000 btus AGA input
214,000 heating capacity
161, net I=B=R rating
671 Net I=B=R rating sq. ft. radiation.

My contractor is telling me that it is correctly sized since I have 275 sq ft radiation of steam radiators, and 100 feet of hydronic baseboard radiators (I don't know how to measure the radiation requirements of hydronic baseboard radiators?) running off of the same boiler, using a direct heat exchanger. He also mentioned that he needs to remove and eliminate the heat exchanger and repipe the hydronic system using the "Bell and Gosett" approach (does anyone know what that is), since the steam unit is clogging the heat exchanger with too much crud.

Additionally, since he just installed this system for the previous owner of my home in April of this year, he feels like I was not the one who hired him. He sees nothing wrong with the fact that he used copper piping on the header (see photos earlier in this thread) and also piped the header without an equalizer or Hartford Loop and with the takeoff to the steam main in the center rather than between the riser and the equalizer.

Does anyone know if any building codes may have been violated so that I might be able to pressure him to fix things? I expect to talk with the building inspector in my village tomorrow, but any advice would be greatly appreciated. I don't know how to convince him to fix it with minimal cost to me?

Unknown

get rid of

Get rid of the so called installer... No matter if u weren't the orginal customer of this contracter, ALL heating systems is suppose to be done in one way, the RIGHT way.... Located and hire a REAL hot water/steam pro to do this job correctly...

Michael G.

Rating my boiler -- how to know if it is the correct size?

My steam radiators have a steam radiation edr of approximately 275.

The Dunkirk that I have installed has the following ratings:

AGA Input *mbh (1,000 btus) 262

Heating capacity *mbh 214 ( I guess that it means that the boiler is 82% efficient?)

Net I=B=R rating *mbh 161 (I guess that is after the pickup factor?)

Net I=B=R rating sq ft radiation 671

I am a bit confused... I don't understand how the sq foot radiation rating correlates with the gross and net ratings? It seems that if we look at the radiator that you suggest, that has an edr rating of 283, it's net i=b=r rating is only 68? And since my 100 ft of hydronic heating is 60,000 btus, I would need to have a boiler that should have at least 180k btus (based on Dan Holohan's "no more than 1/3 of your output from the steam boiler should be used for hydronics). I simply don't understand enough of the ratings systems (between the 671 and its net rating of 161) to have a meaningful conversation with the plumber's supply house. Can you please clarify?

brucewo1b

240BTU sq ft of radiation X Net I=B=R rating sq ft radiation 671 = 161,040BTU or Net I=B=R rating *mbh 161

Michael G.

Bruce

Thanks very much for this. So, if I only have 275 sq foot of steam radiation (or approximately 66,000 btus), it would seem that this boiler is grossly overrated by almost 100,000 btus. The real question is whether or not one needs to add on capacity for the 100 sq ft of hydronic baseboard (approximately 60,000 btus) that is added onto the steam boiler using a heat exchanger and if so, how much?

Michael G.

So if I am understanding this correctly, my 275 sq ft steam radiation translates to 66,000 btus. Given that my 100 feet of baseboard on the hydronic system needs approximately 60,000 btus (or more than 1/3 of the output of a system rated for the 275), wouldn't I therefor need to add capacity to the boiler and if so, how much? Isn't it possible that I would need to have a total gross rating of closer to 180,000 btus (or approximately 571 sq ft radiation)

Michael G.

size of boiler

My 275 sq ft steam radiation translates to 66,000 btus. Given that my 100 feet of baseboard on the hydronic system needs approximately 60,000 btus (or more than 1/3 of the output of a system rated for the 275), wouldn't I therefor need to add capacity to the boiler and if so, how much? Isn't it possible that I would need to have a total gross rating of closer to 180,000 btus (or approximately 571 sq ft radiation)