Air Vent Placement

BAB

What is the ideal placement the air vents?  I use Gorton #1 & #2.  My first installation of the Gortons was near the end of my main pipe runs, furthest from the boiler.  Recently I noticed that on my long pipe mains the majority of the pipe air volume is actually close to the boiler.  For example, 20 feet of 5" pipe and 3" pipe will have more trapped air to vent than 20 feet of 2' pipe.  In round numbers there is three times more air in the large pipe mains near the boiler versus the smaller pipe mains way out there.  I have therefore started to move some of my air vents (Gortons) from the end of the pipe runs to the start of the runs, closer to the boiler. On a 200 foot pipe main I place the Gortons near the end of straight runs & before 90 degree elbows.



I have 5 steam mains each with its own respective thermostat & Honeywell motorized steam valve.  My longest main is about 200 feet long & caused me the most trouble.  It used to take 25-30 minutes for us to get steam.  After we got the steam it would rarely heat the radiators.  Now we get steam in 10-15 minutes & the radiators eventually really cook, all the way across their 14 foot length. 



What is your advice on placement of the Gortons on the long, long pipe main? 

nicholas bonham-carter

"air is the enemy"

you have to let the air out, as quickly as possible, before the steam can arrive at its destination. the motorized valves make this even more tricky, because when they are closed. even when the boiler is firing, they prevent the vents from letting the air behind, and in front of them out. when the valves open, the vents on the ends have a lot of work to do, all of a sudden. you could put vents immediately in front of the motorized valves, to speed up the steam into the various sections. you would still need vents next to the boiler, on the dry return so as to complete the evacuation. i would put plenty of vents at the end of the dry returns, so that you have as quick a response to a call for heat as possible. start with 3 gorton# 2 for each dry return, and see if that is enough.

remember that low pressure steam [ounces] travels faster than high pressure steam [1+ psi]-do you know what your pressure is?--nbc

BAB

low pressure steam

Over the last several heating seasons I have been adding Gortons here & there, never on the condensate line.  Also put in some wide open 1/2 & 3/4 air vent stacks on the dry condensate return piping, usually after & below the radiator trap, also on the condensate drop headers from the steam mains every 20-30 feet.  All piping never sees 1 psi, ... I have no oz per in sq gages so I do not know actual pressures.  We used to run the system up to 6-9 psi during cold weather until I stumbed upon this website and got the message, became a believer.

I understand & appreciate your comments, especially regarding the motorized valves.  I hate working in the dark, reinventing the wheel & your comments indicate that I might be on the right track. 

Steamhead

Vent your steam mains

at their ends, before they drop into the returns. This way no matter how many vents you use, they will all contribute to venting the entire main.