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Sizing a new steam boiler with inlet orifices extisting
Looking for guidance on sizing a new 2 pipe system steam boiler. About 17 of 23 convectors and radiators have extisting orifice plates installed probably original 1931. Should I still install a new boiler to the radiation edr or measure the orifice hole diameters and use that value in the edr calc. I'm concerned that if I install a boiler to the calculated edr which is 859 that it will short cycle on pressure. The existing boiler which was 568 edr never evenly heated my house so I know I need to up size.