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Do I need to bleed my radiators?

Thanks Brad for all of your advice. They were both enlightening and helpful.


  • MiaLisa Morris
    MiaLisa Morris Member Posts: 5
    Do I need to bleed my radiators?


    I rent, and since I been here, a new boiler was installed for my apartment (I pay for my own heat, gas, & hot water). Anyway, I recently ran into a problem with the thermostat and now I have to go to the basement to turn/off the boiler for my heating needs (until the repairman comes). When I turn on the boiler, the radiators are constantly leaking. What shall I do?
  • Brad White_147
    Brad White_147 Member Posts: 14
    Range of Issues

    (BTW, MiaLisa- you may want to re-post this under Heating Questions for more focused responses.)

    I would ask who is responsible for servicing equipment.

    If the radiators are leaking, where does this occur? It it steam or hot water? (Radiator vents are high or mid-way up? One pipe or two into the radiator? Partial indicators.)

    What do you do to turn on your boiler when you go to the basement? Switch or have you maybe twisted some wires together or placed a jumper on the control so that it thinks it is always asking for heat?
  • MiaLisa Morris
    MiaLisa Morris Member Posts: 5

    Thank you for responding Mr. White.

    First question: My landlord is responsible for servicing the equipment.

    I have the cast iron radiators. They are leaking hot water (one by way of the valve, and the other, by way of the pressure control knob)

    When I go to the basement, I turn on/off the boiler by way of switch.

    To answer the latter part, in regards to the thermostat, you are correct, but I don't know if that was my doing. I just recently moved into this apartment 4 mos. ago.

    I had my utility supplier to come and check the problems of the thermostat and that was the conclusion, "twisted that it thinks it is always asking for heat" The service person is coming to repair that problem, as per my landlord.
  • Brad White_147
    Brad White_147 Member Posts: 14
    It could still be a steam system

    if the vents are spitting water, that is just condensed steam. How many valves and how many pipe connections to each radiator? When you say "pressure control knob" I am thinking that is an adjustable vent (1-10 scale and/or "Faster---Slower" on the adjustment?)

    If it is a steam system (this is where I was going with that), then the system could be full of water... Properly, steam is a gas and no liquid should exist under pressure above the waterline of the boiler (if it is one-pipe steam).

    So, if you are running a steam boiler in a flooded system you will have spurting water, whistling, gurgling, ungodly metallic banging...

    Sort of like when a pod of Humpback Whales meets the cast from "Stomp!"

    However, my biggest concern is that you are running the boiler wild, limited by the safety limit controls (brakes on a runaway train). Now it seems it is up to you, physically going down to the boiler as if you were a manual thermostat yourself :)

    I would wait for the pros to arrive, but in the meantime, see if there is a gauge glass on the side of the boiler (another sign of a steam system). See if you can see a waterline.


    Brad (call me Brad. Mr. White is my father. Come to think if it, he is Ernie... so, there is no Mr. White :)
  • MiaLisa Morris
    MiaLisa Morris Member Posts: 5

    Okay Brad :-)

    Thanks again! There is one valve and one pipe connection to each radiator in my apartment. When I said, "pressure control knob, (maybe I used the wrong name - amatuer you know:-)), I was talking about the knob that is located either to right or left of the cast iron radiator which is also connected to the pipe system in the floor. (I hope I'm not sounding stupid).

    Yes, you are correct - "if you are running a steam boiler in a flooded system you will have spurting water, whistling, gurgling, ungodly metallic banging..." This is what I'm experiencing. I will take your advice and wait for the pros, but in the meantime, I will also go down and check the waterline as you suggested.

    Thanks again!
  • Brad White_147
    Brad White_147 Member Posts: 14
    All good questions

    No, nothing you said has anything close to sounding stupid about it- just areas of interest you never had before(and probably did not seek for that matter!).

    The low angle valve is the very same one where steam enters and consensate leaves the radiator. It does this each time the boiler cycles, like a tide only several times an hour, more frequently when cold out.

    This valve- it is important that you leave it fully open or if you want no heat at all in a room, fully closed. Not in-between. It does not "throttle" in a way that would be meaningful to you or anyone for that matter.

    The air vent normally is located on the opposite side from the hand valve.

    Now, what I am about to say is not an indictment or criticism of anyone that comes to look at your system, but there is a tendency for those who do not understand steam heat to crank up the pressure. (More steam is better, right?). Nope. Your system can run on OUNCES of pressure, less than a pound.

    I mention this because if your service person comes in and says, "you need more pressure!" it is a litmus test of sorts. If he or she says that, tell them about this site, Dan's books ("We Got Steam Heat! among others) and how you need less pressure, not more. Just one tip, but it can "filter" the service people and find those that are not really knowlegeable about steam.

    If they insist you need more pressure, insist you need another service person. Stick to your guns. Not to telegraph an issue that may not occur, but somehow you have to trust the service people and how can you know?

  • Roger_7
    Roger_7 Member Posts: 1
    Thatcher Radiators

    How do I bleed these types of radiators. They are full open but not receiving much steam
  • Brad White_9
    Brad White_9 Member Posts: 2,440
    You may want to post this as a new thread.

    Your posting is at the tail end of a thread that has been more or less resolved-

    See the "Homeowners" section for instructions and use the "New Topic" button to get answers focussed on your actual needs.


This discussion has been closed.