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Basic question re: radiator replacement

shulgs Member Posts: 1
Hi everyone,

I recently moved into an apartment that's in an 8 unit building with steam heat. I am considering replacing the large radiator for a smaller one to free up space for seating. But I've gotten a lot of mixed feedback with one vendor saying I would lose heat with a smaller unit and another vendor saying that there are now more efficient radiators that can do the same job. Wikipedia also seems to suggest that there are now steam radiators that are smaller and able to produce sufficient heat (link).

Would anyone be able to help me understand why I'm hearing different answers please? I don't want to move ahead with the work if the heat output will drop significantly or if it causes problems/banging for my neighbors.

Thank you,


  • ethicalpaul
    ethicalpaul Member Posts: 5,585
    edited July 2019
    Welcome! Can you post a picture of your radiator? Show the whole thing and include any pipe(s) going into it.

    What kind of an area does that radiator serve?

    Does the current one provide plenty of heat for that area? (this might be difficult to accurately answer and can depend on some variables like venting)

    Edit: were any of your vendors in the "Find a Contractor" section of this site? You have a (much) higher chance of success if so. See https://heatinghelp.com/find-a-contractor/
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • SlamDunk
    SlamDunk Member Posts: 1,556
    What you need to do is figure out the "Equivalance of Direct Radiation" (EDR) of your current radiator and compare the size of newer radiator with same EDR. If you pick a radiator with a lower EDR, you will have less heat in that area.
  • Ironman
    Ironman Member Posts: 7,347
    The heat output of a radiator is determined by its surface area which is measured in square feet (EDR). On steam, the output is 240 btus per square foot.

    If you decrease the square footage by using a smaller radiator, you'll obviously decrease the heat output. Nothing magical here, just common sense.

    There are hot water baseboard heaters that have higher output, but that's because there's more fin and tube surface area. These don't apply to steam.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • gerry gill
    gerry gill Member Posts: 3,078
    you have to do the math as a starting point, of course. But is the room in question to hot in winter? That would help your answer right there. You may have to go thru a winter to get the feel for that.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • retiredguy
    retiredguy Member Posts: 880
    If you have a 2 pipe steam system and are looking for a type of radiation that does not require a lot wall space, you could consider Burnham cast iron baseboard radiation.