Water in air valve

question

Can anyone tell me why I am getting water in the airvalves? I have a five floor 20 unit building. I get water in the riser air valve which is on the fifth floor. once this happens the air will not escape and the pipe will stay cold.

BobC

Watered down vent

Read this post on a similar problem -  http://www.heatinghelp.com/forum-thread/133400/Radiator-vent-holding-water



Make very sure the piping that feeds that riser is sloping back towards the steam main. Could there be a incorrectly sloped pipe connecting that vent to the riser? Is there a way to block it up slightly to see if you can increase the slope? How long is the main that feeds that riser and what kind of main vent is on it? If the main vent is too small your forcing the riser vent to do all the work for that side of the system.



Post some pictures of the boiler, the near boiler piping from a couple of different angles. take a picture of the main vent and the piping leading to that riser and of the vent (and it's piping) at that riser.



Bob

nicholas bonham-carter

water blocking 5th floor air vent

is this 1-pipe steam or 2-pipe?surely on the fifth floor you should not have a waterlogged air vent. is this a main air vent on the riser pipe, or is it a big radiator vent?

if this is condensate which is somehow not returning /draining down the riser, then could there be a badly sloped horizontal feed at the top? a diagram of your system would be essential for determining what the possibilities are.

alternatively, a combination of over-pressure, and bad main [not radiator] venting could be pushing water up to the top, as the air seeks a way out at the start of steaming.

the  majority of the air must be removed by main vents on the supply/return pipes first. the radiator vents can then start to let the air out of the risers. on tall risers, a main vent is placed at the top on the pipe.

steam flows quicker at low pressures, and many vents can stop functioning at higher pressures. the upper pressure should be no more than 1.5 psi [2psi for the empire state building!].

the aim of good venting is to enable the speedy escape of the air at the start of each cycle, permitting the simultaneous arrival of steam at each radiator. therefore mrs. jones on the north side will get steam at the same time as mr. smith on the south side!

if you are concerned about utility cost, every ounce of pressure above 8-12 oz. is fuel wasted for no good purpose. a vaporstat, and good low-pressure gauge are necessary for maintaining this low pressure.

if this is your building, i would guess that correcting the vents and pressure would pay for themselves in a few weeks, in reduced operating costs.--nbc