Venting

This is a two pipe system? Radiators have a separate inlet and outlet and traps? If so, you can concentrate all the venting for the dry returns at the boiler, however, is convenient, before they join and drop to the wet return or boiler return.

And make that venting generous! You are venting all the radiators (and, in some systems, the steam mains as well!) through those vents.

Not sure if it was previously mentioned in the other thread, this dimension should be as short as possible, it is not.

Looking at the pictures in the original post I don't think there are any traps, maybe orifices somewhere. Maybe originally this was not a steam system, not sure.

Don't know how handy you are. I'd get a torch, solder, flux, tubing cutter, a few applicable wrenches, copper pipe and fittings and straighten out the Drips, wet return, Hartford loop myself. Many pipe sweating tips on Youtube.

Who added the two Gorton #2 vents that seemed to work out OK. You could redo the Drips, wet return, Hartford loop in black pipe if that is better for you but that may cost more in replacement pipe or reuse some of the copper.

I think that will give you the biggest performance gain and fuel conservation for the effort.

" If I have time I will add more vents to the other side of the basement. Just trying to figure out where to put them. "

Ultimately I think you will find more venting on that return pipe than what you already have is a waste of time and money. The object is to have the steam go only in correct direction through the system by venting the air out of the mains and then the radiators. Once enough venting exists more is a waste. I would think two Gorton #2 would be enough on the returns. If the steam is finding a shortcut to the present vents that is messing up the correct process.

An additional vent at the end of the mains or at least the longest main may help since you probably don't have crossover traps to aid in quick venting of the main. Venting the ends of the mains may help. However, I believe you stated you do not have access to the end of the mains. I suppose you could put a vent on the radiator supply pipe closest to the end of the main(s).

Another thing that makes your system awkward or dysfunctional is the lack of traps so steam can't go where is it not needed or wanted possibly trapping air in the system. Trapped air equals no heat when it is trapped in a radiator or prohibits steam form getting to a radiator.

Can you feel how far steam gets into that main? And how fast? And I assume there is a dry return from there? Does it get hot?

How are the pitches on the main and the return?

I assume it's the long straight pipe? Does it get warm or hot when the boiler is running? Which way does it pitch,, can it drain properly? How is it vented at present?

show where that dry return drops down to boiler or wet return(show from the Ceiling to the floor), probably need to fit a vent

Check all the pipe pitches to make sure that everything can drain. That long a straight pipe may have a drain only in the "middle" — and it may well have a flat slope, or possibly even a reverse slope… doesn't take much of a puddle hanging out somewhere to mess things up.

2 thoughts,

1, that the vent heats up and closes before all returns are vented, follow the heat from the vent, back to from where it comes, and stop it there, if it's coming from what looks like multiple returns colliding, you need to separate the returns and drip them to the floor, with each drip having its own venting, or if from that high horizontal crossing drip at the boiler, well, same same, break the path and drip each to the floor, with venting,

2, the kitchen and the cold rad above, as @109a suggests them being parallel, the kitchen heats and vents to the return, trapping the upstairs on its own, add a kludge to your kludged system, try a vent on that upstairs rad,

agree with you @Jamie Hall ,

I meant that steam is getting up to that vent, and it needs to be stopped from whence it comes, whether from returns, or up from the boiler return(s), trace the heat back to its source,

Recently someone made a video then compressed the file size by zipping it and posted the zipped file here and that worked. Normally a video is hosted on another site and the link to it is posted here.

" My drips are getting hot from the mains first as the steam heads out. "

As the steam heads out it should propagate through and heat the mains (only) first then go through the radiators and if any steam is left on the return side of the radiators (in your case, no radiator traps) should only propagate to the vents then the vents should close. Balancing the steam flow into the radiators may be critical in your case. So the steam can't go through a small radiator heating it up quickly than proceeding to the vents and closing them trapping air in the rest of the system.

The drips should not get steam hot since they only should have condensate in them since the water-seal at the bottom of the drips (each drip) inhibits the steam from entering the drips (no gas flow possible). That is why the water-seal on each drip is important to isolate the mains for proper vent operation.

To refresh, can you take a picture like the one directly above but all the way down to the floor.

Thanks but way too close, I can't get the big picture.

" To refresh, can you take a picture like the one directly above but all the way down to the floor. "

The whole view in one picture.

Oh OK, I thought something was changed, the bottom ends of all the Drips need to be well below the water line. Definitely the one in the Red box should be at the level of the Yellow box. I would also move the pipe at the tips of the Orange arrows down also. All join together below the water line then go to the Hartford loop. The water blocks the steam from moving where it should not be moving.