Venting main options

steve_25

I have a 1 pipe steam system with vent tree at the end of main

I'm wondering if there is any options to replace air vents with a solenoid valve that closes when steam fills Main and reopens without losing steam

Boiler set to .5 lb. put never builds presure

Any ideas?

Steve Nichols

it sounds fine

to me.  If your boiler isn't building pressure, it's vented correctly and should be quick to fill the mains.  While it may be possible to hitch up a solenoid, now you are relying on electricity to shut/open something using some type of switch that detects a specific temperature as a tipping point. Bimetallics in main vents are fairly reliable as there are no moving parts in the bimetal itself, just differential thermal expansion.   I'd love to have a boiler that never built pressure, but mine is oversized but aggresively vented. 

gcp13

venting too fast

is it possible to vent too quick?

an maybe cause banging from heating to fast

gcp13

venting

Venting main options

I have a 1 pipe steam system with vent tree at the end of main

I'm wondering if there is any options to replace air vents with a solenoid valve that closes when steam fills Main and reopens without losing steam

Boiler set to .5 lb. put never builds presure

Any ideas?



not building pressure could also be slow leaking air vents ,wasting gas

Jamie Hall

No need

The fact that you are not building pressure simply means that your radiation is condensing all the steam your boiler is producing.  Which is what it is supposed to do.



If there were a steam leak, you would have to be adding water from time to time (you do keep track of how much water you add, if any, don't you?).  Anything over a gallon a week would be cause for at least curiousity, if not concern, in most residential settings.



Specifically to gcp13.  Too rapid venting will not cause banging.  What causes banging -- ninety nine times out of 100 -- is water hammer.  That needs to be found and fixed.  That hundredth time is expansion, and that will bang no matter how slowly you heat the pipe.  It also needs to be found and fixed.  "Slow leaking air vents" will not waste gas -- but see the remark above about steam leaks and adding water.



Low pressure does not waste fuel.  High pressure does.

nicholas bonham-carter

Building No pressure

What sort of gauge is on the boiler? No pressure with the proper sort of gauge (0-3 psi) would give more useful information than a typical 0-30 psi gauge, which most installations have.--NBC

gcp13

Gauge

Good point about losing water.

I keep an eye on water level,and add very little over the heating season

I have a 0-5 lb. gauge from waters on there right now

And never see the gauge move

I tested by shutting all the radiators an the boiler shut off on presure at 1.5 lb.

can't get presuretrol to set lower without switching to vaporstat