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bleeding radiator problem

rick3 Member Posts: 3
I have a 4 story apt building that no fluid (or air) comes out on any radiators on the 4th floor apt.

I'm guessing that there isn't enough water pressure (?)  Does a taller building NEED more pressure to bleed the radiators?

Thinking that I should run the pressure up to 20 lbs (or more?) and then bleed them,..and then drain it down to about 10 lbs?

Do I try to bleed it with the circular on or off?

I  think the pop off valve is set to 15.

Should I run it NEAR  15?    Or is a closed system like this really need to be pressurized above a certain point?


  • JStar
    JStar Member Posts: 2,752

    You need enough pressure to lift water to the highest radiator. If the building is four stories, then you need to set the water pressure at 20 psi, and leave it there. However, you would also need to upgrade the relief valve from 30 to 50 psi, and match the pressure in he expansion tank to the new water pressure. This is a job recommendd only for professionals.
  • Steve_210
    Steve_210 Member Posts: 645

    Check the maximum Working pressure for that boiler
  • rick3
    rick3 Member Posts: 3
    Thank you gentlemen, its an

    Energy Kinetics System 2000. Is there a place on the boiler that tells the max operating pressure?
  • 4-storey pressure

    Is this a new building to you? Has the heating ever worked for the people on the top floor?

    If this is a relatively new instalation, can you get the installer back to rectify the problem?--NBC
  • rick3
    rick3 Member Posts: 3

    It apparently  always been a bit cool.

    I inherited the tenant from the previous owner. He was an older gentleman and keep saying the heat was fine, I find from a friend of his that he was frequently cold but didn't want to say anything because of fear that his rent would go up. (it was quite lower than market)  So he apparently endured and had a electric oil filled space heater as a boost and had a warm room.

    He has since passed away and I'm trying to boost the heat up/ The building has 5 units and this one occupies the entire top floor. (nearly 1500 sq feet) we did some extra insulation in the top of this unit and did a blower door and fixed a number of air leaks.

    Before the new people set to go in I tried to bleed the radiators (boiler running and circulating)  and  and found that there was positive pressure but when boiler cycled off they had a vacuum instead.

    The building has one thermostat and surprisingly the heat is well balanced in the other units,.. 
  • Annual maintenance

    It's time for a checkup of this system, done by a competent hydronics specialist (not just a plummmmer)

    Make sure you are there, and can learn to do the simple jobs of yearly maintenance. He should also be equipped to do a combustion test of your burner. There may be economy features on your boiler which have never been used, such as a 2 stage gas valve. Call now, and see your tennantsSee comfort increased, and your gas bills probably go down!--NBC
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506

    Follow JStars advice. When bleeding, you need to turn the boiler & the circulator off. If the height from the boiler to the top of the highest radiator is 32 feet, you're going to need about 18-20 psi of operating pressure. Look on the relief valve for its pressure rating. It's probably 30psi.
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