Venting the steam Mains

BBQ12

I am new to steam heating and appreciate your guidance on how to size the main venting to reach the 2nd floor as the radiators do not warm fast.
Total piping length (without the returns) is 83'.
2" = 17'
1.5" = 57'
1.25" = 9'
I have two Gorton #1's furthest from boiler and a Vent-Rite #35 on a return next to boiler.
Also, should there be a vent on the left side of the basement?

Thanks in advance for your help!

Jamie Hall

This is two pipe steam? That is, there are two pipes to each radiator (and traps or something of the sort on the outlets?)? If so, part of your problem is that you need a lot more venting on the return. At least one Gorton #2.

And yes, you also need a Gorton #1 where you ask "should there be a vent here?".

Steamhead

Jamie Hall said:

This is two pipe steam? That is, there are two pipes to each radiator (and traps or something of the sort on the outlets?)? If so, part of your problem is that you need a lot more venting on the return. At least one Gorton #2.

And yes, you also need a Gorton #1 where you ask "should there be a vent here?".

This. @BBQ12 , can you post some pics?

BBQ12

Hi Jamie, if I understand your question, it's a one pipe steam (I mean one pipe leading up to each radiator on the 2nd floor)

Steamhead

OK, where does the line with the Vent-Rite #35 return from?

EBEBRATT-Ed

My guess it's at the end of the steam main/dry return

Jamie Hall

If there's only one pipe to each radiator, it's pretty well got to be as you say, @EBEBRATT-Ed . In which case, additional venting on it isn't all that important though it surely wouldn't hurt.

But also, if this is single pipe steam with a vent on each radiator, most of the imbalance can be corrected with the proper choice of radiator vents. There still needs to be another main vent where @BBQ12 pointed out.

Start off by seeing what vents you have on each radiator -- you may need slower ones on the ground floor.

BBQ12

Based on the above diagram for 2nd floor radiators:
Top right (furthest from boiler) - Mist O Maid D
Bottom right - Vent Rite #11
Top left - Gorton C
Bottom left - (closest to boiler) - Vent Rite #1
For the ground floor - it's a separate boiler for another home owner

The Vent Rite #35 is returning from both the left and right side of basement

Steamhead

BBQ12 said:

The Vent Rite #35 is returning from both the left and right side of basement

So that vent handles the return from two separate mains? Where does the return connect to the mains?

Jamie Hall

Steamhead said:

BBQ12 said:

The Vent Rite #35 is returning from both the left and right side of basement

So that vent handles the return from two separate mains? Where does the return connect to the mains?

And how does it connect? Basically straight pipe?

BBQ12

Here's a pic of the Vent Rite #35 from the returns on left and right side of basement.

BBQ12

Here's my Gorton #1's on right side of basement:

Bottom right (of diagram above)


Top right (furthest from boiler)


There is no main on left side of basement (top left of diagram)
Do I add a main here?

Steamhead

BBQ12 said:

There is no main on left side of basement (top left of diagram)
Do I add a main here?

Yes.

And, if the return that the Vent-Rite #35 is on comes back from where the existing Gortons are, you don't need a vent there. Why fill those returns with steam?

BBQ12

Are you saying to remove the Vent Rite #35 and close it off?

BBQ12

Here's a another pic of the Vent Rite #35

Steamhead

BBQ12 said:

Are you saying to remove the Vent Rite #35 and close it off?

Yup.

Jamie Hall

My question again -- how are those "returns" connected at their far ends to the steam mains? Or, to put it another way, are they dry returns, or are they extensions of steam mains? If the latter, they must be go below the boiler water line before they join, or you'll have uneven and erratic heating...

BBQ12

As this is all new to me, how do I tell if they are dry returns or extensions of steam mains?

Jamie Hall

BBQ12 said:

As this is all new to me, how do I tell if they are dry returns or extensions of steam mains?

Trace a steam main. Follow it along its length, starting at the boiler. If it keeps going, without any traps, and keeps going... and comes back as the "return", it's a continuation of the steam main. If, on the other hand, the steam main comes to an end and is connected -- if at all -- to the "return" through a trap, then the odds are good that you have a true dry return.

The distinction is not trivial, nor an exercise in confusing semantics. If it's a steam main or directly connected to one, steam will flow into it (assuming it is vented). Trouble is, if you have two of them the steam will try to come from both directions -- and one way will get to the vent and close it first, at which point the flow of steam in both ends will stop, or nearly so. Now if both ends have already made it to all their attached radiators, maybe not a problem, but if one end hasn't... the poor little radiators will be very slow to heat, since they are depending on their vents alone to allow steam to get to them.

The continuation of the steam main approach is very common, as in parallel flow systems (the mains slope away from the boiler) they allow the condensate in the mains and, in a one pipe system like yours, from the radiators, to keep going along and get back to the boiler.

JUGHNE

To add to Jamie's excellent explanation: each steam main extension needs to drop down to a wet return individually to isolate it's steam pressure from others. And also each extension will need to have it's own air vent on the pipe after the last radiator take off.

BBQ12

I don't notice any traps along the steam main just the loop back (as shown):

Does this mean they are just extensions of steam mains and not dry runs?

Steamhead

BBQ12 said:

I don't notice any traps along the steam main just the loop back (as shown):

Does this mean they are just extensions of steam mains and not dry runs?

OK, so the ends of both steam mains loop back like that and end at the Vent-Rite #35?

BBQ12

Yes, the ends (on right side of basement) loop back to the Vent Rite #35. On the left side of basement, I was instructed (comments above) to add a main vent and to plug where the Vent Rite #35 is. Correct?

Steamhead

Correct. For now that will help keep steam out of those lines. As posted earlier, they really should drop below the waterline before teeing together, but adding a vent where the plug is and plugging the 35 will help- and might be enough.

BBQ12

I'll give it a try and circle back in a few days. Thanks!