how do I stop steam radiators and pipes from BANGING??

the steam pipes leading to several of my radiators bang loudly after the steam subsides, how do i stop this awful noise???

4 Answers

  • 1 decade ago
    Favorite Answer

    It depends if you have Water or steam heat. You shouldn't have to bleed the lines for air unless you have a water system. Water systems are relatively closed systems while Steam heat systems inherently have air in them. They are regulated by the pressure release valves. Everything equal, Steam heat is going to be louder than water. The reason for this is that the pressure and temperature changes between an inactive steam system and the active steam system are much greater then a water system. When the system kicks on and recirculates hot steam into pipes or a radiator that has much cooler vapor in it the temperature difference can causes the pipes to begin hammering. When the 230 plus degree steam hits the colder zone the velocity of the steam entering the radiator is reduced, but the pressure pushing behind it does not drop until an equilibrium temperature is reached within the zone. With the increased volume of the radiator and the drop in the temperature you have a drop in the velocity of the steam. To assure that the steam continues at a velocity that will reach the other zones the piping exiting the radiator will ussually be reduced in diameter to increase the velocity of the steam at the reduced temperature.(when it comes to piping-volume and velocity are inversely proportional) The Hammering of the pipes as the steam enters the zone is controlled by the release valve and the fact that the radiator has a larger volume than the pipe that is supplying the steam. The reason you are experiencing the hammering after the release valve has been activated is that the steam is being forced into the pipe exiting the radiator as it heads to the next zone. Once again the discharge pipe has a much smaller volume and is cooler than the radiator.(Increasing velocity with a great temperature difference) The difference is that the pipe does not have a pressure release to relieve the pressure until it reaches the next zone. The pressure exerted on the piping causes the noise you are experiencing.

    I bet the noise is more pronounced when you kick up the thermostat 5 or 6 degrees. Try to avoid drastic temperature changes. Maintaining a constaint temperature will reduce the internal temperature changes of the system.

    Have a Mechanical engineer that specializes in Hydronic heating take a look at the system. Have him look at your release valves they may not be functioning as intended. He would also be able to tell you if you have any improperly sized piping. Hammering is often caused by improperly sized pipes. Remember a too small a pipe increases the velocity which increases the pressure which causes the noise.

    I'm sure it's more than you wanted to know. Sometimes I get carried away. Good luck!!!

    Source(s): I'm a physics geek and a r-key-tekt
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  • falls
    Lv 4
    4 years ago

    Steam Heat Banging Pipes

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  • 1 decade ago

    Make sure that you bleed every radiator of all air. The expasion tank might have to be replaced also.

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  • 5 years ago

    difficult matter. do a search at search engines like google. this can help!

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