Main Vent Placement

jeff_72

I have a one pipe steam system with two mains running around the perimeter of the basement. The main vents are NOT set back 15" as Dan suggests, but right on the end of each main on a T. The top of the T goes up to the vent while the bottom of the T goes down to the drip connections. The system runs quiet. Can there be a negative effect on the system having the vents at the very end of the main?

Thanks

Bob W._3

I have the same venting setup. All I did was take out the old vents at the top of each Tee and then installed the new vents above Y strainers. Since I used two vents per main, I piped one vent on top of a Tee off the strainer and the other back and then up off the same Tee. Works.

Long Beach Ed

The main reason...

...to set them back from the ends of the mains is to protect them from water hammer. One good episode of water hammer will wreck them on the ends of the mains.

If the mains don't hammer and the system is piped right, just leave them alone. Or you can put them up on a 6" nipple or so and gain a little protection.

clammy

as ed says

As ed says add a nipple to raise the vent or as i do use 2 45's and a few extera nipples and give yourself a offset to raise the vent and give a little resistance to the water hammer i have had good results with it i even do it this way when my vent tees are cut in in the proper location just my 2 cents peace and good luck clammy