2 vents one radiator

alanm

Follow up to a previous question. Does anyone know if tapping a 2nd vent into a radiator (so there is two vents instead on one) does anything to help or hinder heating a radiator.

Fred Harwood

two vents

Shouldn't hurt, but no substitute for fast mains venting.

Mike T., Swampeast MO

Figuring the REAL steam pros...

...weren't sitting in a cozy office waiting for contact cement to dry I decided to put my books to good use and attempt to answer this question.

Went through the 5 good heating texts I have here from the 1900s - 1950s. None completely devoted to steam, but figured surely....

Found out:

1) Rads on single-pipe systems need an air vent. Duh!

2) An automatic air vent is preferable to manual. Double duh!

3) Automatic vents should be installed as low as possible (because steam is lighter than air) on the radiator but manufacturers often located the "spot" rather high to avoid problems with condensate backups.

Found a few illustrations of various automatic vents but, beyond the above--nothing!!! No mention of the speed or size of the air vents. CERTAINLY nothing about "double" air venting.

From what I've read here, two air vents are sometimes installed on really large radiators that fail to heat fully during a typical steam cycle with the fastest available single vent. I believe that if one is high and one low (using the "cast in" vent spots on most rads) that the upper will close rather early in the cycle with the lower continuing to vent quite a while longer.

The author of one of those books uses a particularly dry and very "by the numbers" writing style. I'd never really read the sections on steam before as I don't work with steam systems. I found it interesting that is style changed considerably--particularly regarding one-pipe steam. He almost became witty with "choruses of hammers" and other "hauntings". Again, while he is VERY much a stickler for calculation and "real" numbers in other sections when it comes to one-pipe steam it's "if you're even close [regarding pipe size] go up a size because if you don't those little things that weren't perfect to begin with will start the hammers, haunt you and the word will spread that you don't know your business."

Interesting....

Steamhead

It's usually done

to get steam to a hard-to-heat radiator. But it's better to install a properly sized main vent and fill the main with steam before it starts going into any radiator run-outs.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Contractor"