Trap?

Jasper02

Is this a main steam line trap?

JUGHNE

Assuming the bottom of those 2 pipes are just connected to each other and no other pipes, that would be a "water seal" to prevent steam from traveling from one pipe to the other.
The bottom of the water seal must be below the water line of the boiler, 28" for each PSI of boiler pressure.
Higher pressure can push the water out and break the seal.

That loop would be eventually filled with water and is a good place for sludge collection. The union at the bottom would let you look inside.

Jasper02

Thanks. Trying to determine no heat output on 2 Pipe steam radiator farthest from the boiler, with a working HW radiator valve. This radiator is the only one in the house that is not heating at all. Any ideas?

JUGHNE

If this is steam, and that rad is connected to the water seal loop, how could air get out of the radiator?

Jasper02

It is not. Radiator is on the 2nd floor.

JUGHNE

This is steam or hot water?

You can remove the TRV temp control thermostat portion only and valve should open completely for trouble shooting purposes.

Air vent or bleeder?

Jasper02

Steam. Have 210 degrees at pipe clamp, almost to valve, but not through valve into radiator. No air vent or bleeder on this radiator.

Jamie Hall

Where does that outlet pipe go?

Jasper02

With TRV removed, there is a small burst of heat to the top corner of the radiator, but fades fast.

JUGHNE

How about other rads up there, air vent?

Jasper02

No air vents on the other radiators.

JUGHNE

Close up of the outlet elbow?

Is there just one loop seal in the basement.

Maybe more pictures of boiler piping and basement air vents.

KC_Jones

2 pipe systems the vents are in the basement. I think you need to get down there and evaluate all the venting for function and quantity. The air isn't getting out for some reason.

Jasper02

Near boiler piping picture attached . The original installing contractor is nowhere to be found. Will scour the basement main steam pipes for air vents.

Jasper02

Radiator outlet connection.

Jasper02

Additional pictures of near boiler piping.

Jasper02

Better picture of water seal. Supply left / Return right, appears to be 1" that reduces somewhere in the wall to 3/4"

reggi

The furthest radiator , other than not heating how is this radiator different than the rest of the system ? 
Do they all have TRV's ? return ells ? Did you open this one and check for blocked baffles or check ball stuck? 
If this is the only one not heating, and you got heat by opening the trv it seems somewhere from this radiator (outlet) and/or beyond you have something not letting air out of THIS radiator... and no steam can enter... Start at the outlet and work your way down...
Just the way I'd go at it... follow the flow..g/l

Jasper02

Radiator has been removed and is clear. Using a shop vac on the return stub; the system pulls a vacuum and is equalized once shop vac has been removed.

JUGHNE

Are all the rads in the house set up the same way?
TRV...elbow outlet....no air vents on rads?
And the rest heat well?

The water seal loop will stop steam and air, somewhere on the return side of the loop there must be some method of air removal.
Could be between the loop and return at boiler....on the return pipe of course.

Jasper02

All radiators are set up the same way. No air vents. Other radiators...all are heating well. Not all have TRV.

mattmia2

Check for an orifice plate in the inlet, make sure it is clear. Look at where the return piping goes, look for a low spot that is trapping water and keeping air from getting back to the main return.

Steamhead

This is probably a Tudor system, which originally had orifices in the radiator valves. These were also popular in Europe. Go here for more:

https://heatinghelp.com/heating-museum/european-heating-systems-circa-1907/

I'll bet the other radiators are heating fine, and passing steam into the dry return which then closes the air vent before steam reaches that last radiator.

JUGHNE

So if he throttled down all other rads to heat across only 50-75% across, meaning no steam going into the dry return.....then the last one may start to heat as the air vent opened....where ever it is located.

Jasper02

I appreciate all of the help. Thanks for the insight. Everyone stay safe.

JUGHNE

Please let us know of your findings.

You might have orifice plates in the inlet valve unions on those without TRV's.

mattmia2

Ideally they would all have orifice plates that would keep steam out of the returns in combination with a vaporstat on the boiler.

Steamhead

@Jasper02 got in touch with us- this is near Baltimore, going to look at it on Friday.

reggi

My money is on blockage at the radiator inlet , or outlet or that Waterloop seal is plugged solid

Steamhead

We looked at this today. Turns out it's an ADSCO system, not an original Tudor like we've seen elsewhere in Baltimore. We found several original radiator valves- here's the name on one:



The union return elbows are 3/4" on this system, which is another ADSCO characteristic:

Steamhead

Like most Vapor systems, the ADSCO routed the air from the radiators to one central point near the boiler. Referring to "The Lost Art of Steam Heating", we find that ADSCO used a cylindrical condensate receiver to operate the draft dampers on the old coal boiler. This is where it was mounted- the pressure scale is still there:

Steamhead

The problem we were looking to solve was one radiator at the far end of the system that would not heat. It wasn't a piping issue. So we checked the dry return, and guess what- no vent!

We removed the plug for the former top connection to the receiver-regulator, and mounted a Gorton #2 vent as high as we could:





Now that radiator gets hot, and the whole system heats faster.

There's more work to do here- several small radiators and Baseray units need to be orificed, to keep steam out of the dry returns, and the near-boiler piping requires Sawzall surgery and repiping. The boiler is a Utica PEG-262, which requires a 3-inch header, and of course the installer could not be bothered to use anything larger than 2-inch. But the owner's young son now has a working radiator.

reggi

Nice.!  Good you were able to get out there to get that figured out and have a good look at the System....@Jasper02 👍