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Switching radiator off and on?

Hi all, long story short, is it okay to switch a radiator off and on on a daily basis (at night)?  It's a one pipe system.  Do I need to worry about the return water being cold and cracking the boiler when I turn the radiator back on in the morning? 
Thanks for the help.


  • Waher
    Waher Member Posts: 251
    Why are you shutting off a radiator on a daily basis? It is better to solve that problem than create a new one.

    If you really need to shut a radiator off each day, do not do it with the supply valve, install an adjustable air vent like the Vent-Rite #1 that allows the radiator to be shut "off" by turning the vent all the way down to "1".

    Supply valves in one pipe systems should always be fully open unless a radiator is being repaired/replaced to allow condensate to drain back to the boiler. Water pooling in a one pipe system creates various problems.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,837
    Let's assume that you have been doing this already. Have you had any noticeable problems with the valve, radiator or the rest of the piping? One pipe steam valve to radiator must be fully open to operate or fully closed to stop that radiator from getting any steam.
    there is no in-between on one pipe steam. You can slow down how fast a radiator heats by slowing the air vent or increasing the air vent. Steam and air don't mix so if there is air in the radiator, and it cant get out... the steam will not be able to get into the radiator. Vent the air slow and the radiator heats slow. Vent the air fast and the radiator heats fast. Don't vent the air at all, and the radiator will not heat at all. So an adjustable vent or even a small valve between the radiator and the air vent may be the better way to accomplish your goal with minimum system trouble.
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • NewJerseyKirk
    NewJerseyKirk Member Posts: 4
    Thanks so much for the quick replies. I've been turning it off via a big ball valve on the one pipe.   The reasoning is my wife bought new drapes that cover the radiator when closed.  We only have the drapes closed at night so have been turning off out of fear or fire or damaging the drapes. The heat isn't on much at night so the house temp bit hasn't been a problem, but don't want to damage the system.
  • KC_Jones
    KC_Jones Member Posts: 5,737
    The steam radiators don’t get even remotely close to hot enough to start a fire.

    The sun coming from outside will do far more damage to the drapes than that radiator is capable of.

    I wouldn’t bother doing anything with it.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • pecmsg
    pecmsg Member Posts: 4,847
    Just let it run.