Main venting

jiggy72

Looking to replace old main vents with new ones. I have 3 mains in home (single pipe system) 60’ 40’ and 20’ long. I was split between Gorton 2 and B&J Big mouth. I see some people have multiple vents on a single main, should I have more than 1 vent on longer mains?

nicholas bonham-carter

Yes, and you could tell when you have enough main venting by using a 0-3 PSI gauge, in addition to your 0-30 psi one.
keep adding main vents, until you can see only a couple of ounces on the gauge as the air is being pushed out.
A rule of thumb is one Gorton 2 for each 20 feet of 2 inch line, but as the goal is to have almost no back pressure impeding the air on its way out, the low pressure gauge method is more sure.--NBC

jiggy72

Thanks for the feed back NBC. So for 60’ of 2” main I should have 6 Gorton #2?

JUGHNE

One Gorton # 2 for each 20 feet of 2" main would be 3 G2's for your 60' main.
One B&J Big Mouth vents about double of one Gorton 2.

They are about the same price for each vent.
The BJ looks to be the better investment.

jiggy72

So I’m thinking 2 b&j big mouth vents for 60’ 2” main, 1 b&j for 40’ 2” main, and either 1 Gorton #2 or 2 Gorton #1’s for 20’ 2” main. Does that sound right? Should I be rearranging vents based on main length and pipe size?

gfrbrookline

I would round up and put 3 big mouths on the 60' and 2 on the 40', you can't over vent the mains and massing out the vents worked wonders on mine, one 60' one 40'. Thank you New England Steam Works. No more short cycling and more even heat.

jiggy72

ok i ordered big mouths for the 2 longer mains, but the short main (20' 2" main) I don't know if 1 gorton#2 is too much/just enough or maybe i should put 2 Gorton #1's would be enough?

**side question....most pics i see show 2 mains on majority of steam systems...i have 3 mains...is that uncommon?

Fred

A Gorton #2 on that 20' main should be fine. Also, three mains isn't unusual, especially on larger systems or larger houses. In many cases, even when there are just two mains off of the Header, one or both mains may branch off further down the line and need vents on those branches as well.

jiggy72

Is blue Teflon tape enough when installing main vents? Or should pipe joint compound or pipe dope or some other alternative be added too?

Fred

Teflon tape is fine and will make it easier to take the vent off to clean or replace it, in the future.

jiggy72

Thank you Fred

jiggy72

So I put main vents on, 2 big mouths on long main, 2 Gorton #1’s on short main. Anything I should change (piping setup)? Or it looks ok?

Fred

Nice job. It's hard to tell from the pictures but I assume you have a little pitch on those antlers that the vents are mounted on, to allow condensate to drain back into the main/return. Doesn't take much. If it holds water, turn your 45's just a little to get the pitch (if you don't already have it)