Need help with steam radiators - not getting heat

JPop78

We've had problems in our house for years with the radiators on our second floor. Aside from the small radiator in the second floor bathroom, the three bedroom radiators haven't been getting heat at all for years now. I went to a hardware store the other day and asked him about it, and he said we might need to replace the vents.



Here's a picture of one of our radiators along with the vent:



<img src="http://farm4.static.flickr.com/3518/4050740379_c9f944beee.jpg" />



<img src="http://farm3.static.flickr.com/2470/4050740121_83cb07efa6.jpg" />



I removed the vent from the top of the radiator and went down to the basement to our boiler. I opened this handle:

<img src="http://farm3.static.flickr.com/2512/4050741207_278ca7cec1.jpg" />



And I released some water into this tube, up to the fill line:

<img src="http://farm3.static.flickr.com/2748/4051482914_a6511a6552.jpg" />



I kept repeating this process until the water level stopped dropping. Eventually, the radiator began to warm up, and steam came out of the hole where the vent used to be, so I replaced the vent. Once I screwed the vent back on, the radiator began to lose heat again.



Is this a problem with the vent itself? If so, is there anything I can do other than replace the vent? Since the radiator got warm when the vent was taken off, can I just leave the vent off, or will this cause problems?

nicholas bonham-carter

plugged vent?

see if you can soak them in vinegar, with the boiler switched OFF, thermostat set extremely low, and cooled down 30 minutes. give them a good shake in soapy water first, then soaking in white vinegar 1:10, for an hour or so. see if you can blow through them, vertically. finally replace the vents, using teflon tape on the threads. don't forget to turn the boiler on.!! you do not want the boiler to fire at all with the vents removed

if they are still plugged, you may be able to use pipe fittings to enable the use of less expensive vents, which are 90 degree vents. your main line vents are probably also plugged, and would make the system much more economical,  but this procedure may get you going in the next few hours.

to learn how to maintain the system yourself, get a copy of "the lost art of steam heating" available here.--nbc

Unknown

radiators.

You really need to have a professional steam man look at your steam system. Without a lot more information it's hard to determine just what it needs and it sounds like it needs more than just vents.  

JPop78

re: plugged vent?

Okay .. where can I find the mainline vent? Is there any way that I can unplug it myself? I don't have any experience in radiators or anything, so this would very much be a DIY kinda thing. If not, that's fine.



Thanks for your help anyway.

Unknown

Steam System Diagram

I have attached a diagram of a typical steam heating system. It shows where  the standard components in a steam system are located . Most "no heat" problems with radiators are related to venting problems, either with the main vents or the vents on the radiators. Each main needs to have its own main vent and each radiator needs to have its own vent.

What the vents do, is allow air to escape from inside the piping /

radiators but stop the steam from escaping. When the pipes / radiators are cold, the vents are open and air can move out of the pipe and be replaced by steam. As soon as hot steam reaches the vent, it closes.  If the vents aren't working, the air can't escape and the air then blocks the steam from entering the radiator.



The first thing I would do is make sure your main vents are working and replace them if necessary. After you have the main vents  working you can then check your radiator vents.

See if there are any names and model numbers on your vents and we can then possibly tell you what to replace them with.