Steam Install

RTW

In a single pipe steam system, I am adding two 24 inch window height 4 tube radiators with 1 inch valves to the second floor of an older Cape style home and want to size the pipe off the main nearest the boiler with 1 inch to 3/4 inch where it 90's to the second floor bedroom #1, and size the pipe furthest from the boiler (at the end)with 1-1/4 inch off the main to 1 inch where it 90's to the second floor bedroom #2. There are some structural reasons for this preference as well.

RTW

Mad Dog

3/4\" will give you problems

you also don't say how many sections the rads are. You need to know first the heat loss of the room, then how big your new rads need to be via EDR. Do yourself a big favor: Buy The Lost Art of Steam Heating and the new book Got steam heat (both avail. here) . If you can read them and understand them, you might be up to this job. Otherwise get a steam pro in there.

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