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Can I put in smaller radiators?

slimline radiators are not meant for steam. Steam needs a lot of room to do it's work. It would be like putting Sylvester Stallone in a Mini Cooper.

Comments

  • Jeff Nichols
    Jeff Nichols Member Posts: 2
    Can I put in smaller radiators?

    We just moved into an older house, part of which is heated by steam (1 pipe) radiators.

    I would like to put in smaller radiators in several of the rooms (and even eliminate them in others).

    I realize smaller radiators means less heat, but we tend towards keeping the house colder anyway (blankets/exercise is always cheaper than more heat!).

    So, what is the best way to go about this? And are the slimline, wall mount radiators a good bet? However, they are quite expensive.

    Thank you.

    Jeff
  • Jed_2
    Jed_2 Member Posts: 781
    You're headed for trouble

    thinking like that. You will effectively oversize the boiler you have, causing short cycling, and costing you more in the long run. Are you prepared to replace the steam boiler to match your downsized radiation load? Even if you don't replace the boiler, and set the thermostat down, the boiler will still short cycle, costing you money going forward. Put one pipe thermostatic radiator valves on the radiators, turn down the rooms not used, or used, and save some money.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    turning off radiators

    until you get the TRV's installed, you may be tempted to use the hand valve to turn off some of the rads--DON'T DO IT. far better in a pinch to turn the old hoffman radiator vents upside down, and then they will not let the air out, or the steam into the rad!

    use the time [and money] you save not removing the rads to make sure that your main line venting is more than adequate, and that your pressure is below 16 oz.--nbc
  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    besides

    TRVs are cheaper... and give you real flexibility!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Jeff Nichols
    Jeff Nichols Member Posts: 2
    I believe they do have TVR...

    I guess I'm not sure about the short cycling--the demand is the demand, right?

    And I was very surprised at the current set-up, especially upstairs. In the 2nd largest room, there was the biggest radiator--doesn't make a whole lot of sense.

    Also, my limited understanding was that older systems were "oversized" due to limited insulation in the outer walls. Now that there is insulation, then one could argue the boiler will "short cycle" due to less demand.

    So, what does one do when renovating? For example, we had a strange "extra room" right next to the bathroom--if we combine the space, we would have not one, but 2 (rather large) radiators in the bathroom. Short cycling or not, I don't have the room for that kind of setup.

    As for the "slimline", I know many are for forced hot water--I was referring more to ones found here: http://www.steamradiators.com/

    Sorry to keep at this, but if the valves are in the off position, then there is no demand on the system. How is that different from less demand using smaller radiators? And by my limited understanding, in the warmer months, there is NO demand on the radiators, whether they are open are not, so during that time, one could argue that the system is oversized.

    Thanks for all the help with this--just want to try and combine the best of both worlds.
  • Matt_72
    Matt_72 Member Posts: 2


    By oversized and short cycling they are referring to the effective surface area of the radiators and the steam production capacity of the boiler. The boiler is always producing the same amount of steam, so if you remove or downsize radiators, the radiators won't be consuming all of that steam, so the pressure in the steam mains will increase quickly and the vaporstat or pressurtrol will shut the burner off while the t-stat is still calling for heating. The vaporstat cycling will be short and will consume more fuel starting and stopping and constantly re-heating the boiler if the amount of radiator surface area isn't fairly well matched to the steam output of the boiler. This is more or less independent of building heating load. Sometimes the boiler can be fired at a lower rate, but that also tends to reduce efficiency and make the boiler soot up. I'm not sure where I see how TRVs don't cause the same issue.
  • Larry C_13
    Larry C_13 Member Posts: 94
    Buy Dan's books

    Get a copy of Dan's excellent book, "We Got Steam Heat". (Top of this page Online Store) It is written for both the homeowner and the professional. From there you can understand what these guys are talking about. Some of the US's most experienced Steam Men are on this site. I would listen to what they say.

    Larry C (home owner)
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