Will this work?

1hvacman

JUGHNE

Does it gurgle?
How long does it take to fill the rad completely with water?
(assuming steam...not a hot water conversion)

And you need a shorter screwdriver handle to get the front cover back on.

ratio

To quote my favorite celebrity:

Gosh

So close, and yet so very far.

1hvacman

That’s what I thought would happen. I haven’t seen a trap on the leaving high side.  Yes it’s steam.  Looks like I have to repipe it. I have two of them.   Here’s the leaving side on the second one 

ratio

Are you going to have to lift the condensate, or is there a low return nearby?

1hvacman

Have to lift it. About 9 ft 

JUGHNE

Are these basement radiators, did they ever heat and how high is the dry return above the radiator?

Gravity comes into play here for condensate water return. If there is any return piping on the floor under this that may work out.

1hvacman

Yep in the basement.  No one left that knows if they ever worked. Return is in the ceiling 

Jamie Hall

9 feet is 4 psi -- much too high for a steam heating system. If that's where it has to go, you'll need a condensate receiver for those radiators and a vent on their return lines and a pump. There are better ways to do this...

mattmia2

It looks like someone rotated them 180 degrees.

1hvacman

System is set at 10 psi.   Only my second day in this building.  Leaks everywhere. I’m hoping once all the repairs are done I can lower the pressure 

1hvacman

They might be upside down. These are the only ones of this design 

JUGHNE

IIWM, I would lower the pressure now.

This may eliminate many of the leaks.

That pressure running for years may have wrecked some components.

1hvacman

It has. I’ve got twelve valves 7 traps and 5 vents  to replace. 

delcrossv

Make a hot water loop for them?

EBEBRATT-Ed

@delcrossv said

Make a hot water loop for them?

That's what I would do

reggi

The second radiators trap is painted like it's been on that radiator for 100 years.. well at least from the 60's-70's as that paint color is familiar to a bathroom remodel color I've seen..
The pipes don't appear altered. .. Change out the cage units and give it a try.. it could be air bound.. remember..if Air can't get out.. Steam can't get in "
😉

Jamie Hall

If you really are running at 10 psi... I would assume that all the thermostatic traps are ruined, for starters. And that all valve packings are leaking steam and will need to be repacked.

Get the pressure down. If the pressure was needed to provide lift for those two radiators -- and that may be why it was done -- it was not a good thought. I'd make those into a hot water loop.

JUGHNE

If you could raise the rad up so the outlet is well above the boiler water line and then have a wet return line on the floor going to the boiler return, they may work after you add air vents on the rads....I know the return line may not be possible for distance and/or foot traffic

IIWM, I would disconnect and cap the piping to the bsmt rads.
Set the pressure down to 2 PSI or less and resurvey the situation.
Valves may not leak any more.

Are they all TRV's?

Could we see the boiler piping that includes the return?

reggi

I think @JUGHNE has the right idea.... have you sketched out any of these back to the boiler or source to see what the original system feed for these two were ? 
I'm going assume that these 2 aren't going to be the only surprises you'll find.. they're probably just the most obvious...

And one more thing.. check which way they're pitched and check the center bottom Nut , in the first photo it's paint is chipped as if perhaps the radiator would perhaps eventually start filling with condensate and every so often they may of had to manually open the bottom and drain the level down.. until one day they died and took their secrets with them.. and until now everyone just kept turning up the pressure... @DanHolohan time to uncover the secrets of this system 

1hvacman

Thanks all. I’ll upload and update once I get back to that building. It may be a week or two