Radiators Using A Steam Vent

Radiators Using A Steam Vent

radiator steam vent

Do you have cold or partially heated radiators when there is a call for heat? If you’re having trouble with cold radiators, find out what can simply and inexpensively correct this problem. First you have to know what type of heating system you have. Do you have steam heat with radiators that have one pipe feeding each radiator? If you do, that means you have a one-pipe steam heating system. How would you be sure? Well, first there would be one pipe entering the radiator on the left or right side. Second you will see half way up the radiator either on the right side or left a cone-shaped device that is called a steam vent. Now that you know what type of steam system you have we can move to a solution.

One pipe steam systems…

In a one-pipe steam system, each radiator has a single pipe connection through which it receives steam and drains condensate at the same time.  All of the radiators and the end of the supply main are properly pitched above the boiler water line so that condensate flows back to the boiler by gravity.  The condensate that drains down from the radiators and steam supply piping all go back to the boiler where it can once again be turned into steam and returned to the radiators.

How do they work?

A one pipe steam heating system uses a thermal air-vent or “steam vent” located on each radiator throughout the heating area of a home or building. Without the normal function of a steam vent, the heating system will not work properly. A steam vent works like this when the heat is off the vent is always open to atmosphere, and the radiators and pipes all contain air. When a call for heat begins, the boiler produces steam, which pushes air ahead of it throughout all of the pipes and radiators in the heating system. The air exits through the air venting valve on every radiator and a main vent. The vent closes off from heated alcohol inside it vaporizing, this exerts mechanical force on a float closing off the vent and preventing steam from escaping the radiator. When the call for heat has ended, the alcohol in the vent cools which reopens the float allowing the condensate from the radiator to drain back down to the boiler, and be reused to make steam.

radiator steam vent
Radiator Steam Vent
main steam vent
Main Steam Vent

Cold Radiators

Radiators that don’t heat up in a one pipe steam system usually can have these symptoms, and they are:

  1. Radiator valve stem broken in closed position
  2. Steam vent is not opening
  3. Steam vent is stuck open

If the radiator valve is being used to control the steam to heat the radiator it sometimes may fail closed preventing the radiator from heating up.

Is this confusing?

Don’t worry about about all those details of how your steam heating system works. Leave it to a experienced steam heating expert who knows the details and can efficiently and affordably solve your problems. Schedule an appointment with Vince.

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