Slower Venting = Faster Heating?

Big-Al_2

Recent topics here have made me more curious about my radiator vents. Last night I switched the vent on a second floor radiator at the end of a main from a VariValve to a much slower Maid-O-Mist vent, trying to quiet it down and eliminate the occasional drop of water.  I was wondering how much slower the radiator would heat up.  I didn't time it, but it actually seems to heat up faster.  I did observe that the big vent would keep closing and opening as the radiator heated up, slowing down the process.  The smaller vent seems to stay open until the radiator is hot all the way across and then close.  It's really quiet too . . . virtually silent . . . no more raspy breathing sounds. 



I'm thinking that the old vent was so big that the steam blew past the air and hit the vent before it could fill the radiator, and that the new vent held the steam back just enough that it filled the radiator more  evenly.  I thought this could happen. Obviously, if  the vent was super slow, it would hold back the steam enough to slow down heating . . . but there must be some optimum speed, beyond which the venting becomes so fast that it is ineffective.   Anybody else have the same experience?  Is there anything published about this, with radiator size vs vent size charts?  Any other possible explanation?



By the way . . . I added a Watts vacuum relief valve to my main vent antler and . . . . no more shutdown sucking sounds upstairs . . . Little things like that make me so happy . . .

gerry gill

yup, i've come to hate vari vents

as radiator vents, but i use them on the steam pipes on occassion as a mini main vent with great results..ive found that i have no problems with venting fast so long as i stay with gorton vents..but the vari vent vents much faster than the fastest gorton radiator vent.