Posted by jtown on October 01, 2001 at 06:29:42:
In Reply to: Steam vents "gurgling" posted by Chris Russo on September 30, 2001 at 14:50:45:
Gurgling is water not draining out of the vent when cooled and pressure dropped enough. Then the new steam is gurgling through it. Sometimes there is a little "tongue" of sheet metal to let water out while steam or air goes over it. Make sure the vent is vertical so the float isn't hanging up. Make sure they aren't painted over. Some can be taken apart to clean with vinegar and soft brush. You should have a spare or two to switch them so you can get some sleep. Don't let them hiss. Replacing the water brings in corrosive oxygen laden fresh water. Plus you can be building up excessive water in the vent that will need draining on the next off cycle (steam can go places liquid can't, through small openings like GoreTex and uphill). In the vent there is a little bottle filled with a liquid that boils at about 212F. The bottom of the bottle expands out and pushes the needle on the top of the bottle into the hole you see. The bottle can float up in case the system gets flooded also.
Hoffman, Gorton, Danfoss are a few of the big names. Don't count on adjusting much. Set the hole to the size of the radiator and how far away from the blr. There are thermostatic vents that work good for rooms that are too hot from solar etc. The first cycle from night set back, etc. they won't work as the air is out of the radiator and steam can replace the steam that condenses. Check your main vents in the basement and top of risers(in big bldgs) while you're at it.