New Century House with Two Pipe Steam - Questions

What trim is on the radiators? Looks like it is some sort of vapor system with traps. also doesn't look 1914, like maybe they added central heat in the 20's or 30's and that i the original boiler. Do the radiators have metering valves on the supply? Do they have taps or some sort of return device or a plain elbow on the return?

Radiators not heating is usually either returns that can't vent because of things like failed closed crossover traps or trapped condensate or steam in the returns from steam blowing through radiators or failed open traps or return connections above the water line (although that is unlikely here since it seems to be the original boiler)

It could be a main has sagged and is trapping condensate keeping that main from heating but that is not super likely here unless something was changed.

We need to see a radiator to tell you where to look.

It's a vapor system. You need the LAOSH as @jughne mentioned.

You have steam traps. No air vents needed except near the boiler probably on top of the "canned ham" boiler return trap.

You have the correct metering valves on your radiators. The canned ham @EBEBRATT-Ed refers to is the black barnes and jones return trap with the sight glass. This:

Also, what's with the top pipe here? Is there a plug in the end?

Are the 7 non heating rads on the same main, or randomly distrubuted?

Lastly, how long does it take the good rads to heat?

Do the radiators that do heat have that extra nipple and elbow on the hot water vent tapping on the radiators?

@delcrossv "Also, what's with the top pipe here? Is there a plug in the end?" If I had to guess I'd say that was a humidifier and a boot dryer/warmer. The pipe would be a drain so ti didn't over flow onto the radiator. Just a guess as I've never seen one like it.

You can try some penetrating oil on those valves. Take it easy to try turning them.

Take care with them, new regulating valves are very expensive.

That's your vent.

As you're not running under vacuum anymore, you can remove ( AND SAVE) that little black ball. See if it vents air with the ball removed.

It depends how tight the system is. If it is relatively leak free it can draw a vacuum but that is the least of your current problems.

There should be those vent traps at the end of each main and they all need to work. There also needs to be a way for the returns to vent because that is how the radiators vent. If it isn't venting it may compress the air enough to allow some steam in to some of the radiators.

@Hedwig595 , when you get a chance, could you get a close-up of the name on that radiator with the built-in humidifier? I don't think we've seen one of these before.

Wow. Just wow. Not only is it a vapour system — and an early one — but everything is still more or less there! You must get LAOSH, and you will find your system, or at least the basics for it, in there.

I would suggest, in this order:

First, check all the traps. Any radiator which isn't heating the trap is suspect. If you find a radiator where the outlet from the trap is close to steam hot, that one is suspect too. Replace any traps which you even think are bad. Both Tunstall and Barnes & Jones make innards to fit them.

Second, you can try to get the valves to move — and WD-40 is as good as anything — but if the don't, don't fret it. If the traps are working they are in the nice to have but not critical category.

Third, buy a good low pressure pressure gauge — to 0 to 3 psig — and figure out where to put it. And put it. Best bet is going to be to put it on a T off of whatever pipe connects the vapourstat (which is set properly, by the way) to the boiler. Clean out that connection which you are at it. That will tell you what pressure you are really at, at which point you decide whether the vapourstat need to be replaed.

Now. Take a deep breath and find you system, or one as like it as you can, in LAOSH and study it. Go down to the basement and study the piping. Go back and study the diagram and texts some more. Until you begin to think you know how that thing worked.

You are going to be the expert on it, so take some time to really be the expert!

Don't do ANYTHING other than those three steps above until you are feeling pretty good about the system. Then work on bringing it back to its former glory.

One further thougth. That boiler. What condition is it in? If it's in good shape, leave it for the time being. Yes it is using more fuel that a new one might. But… for now leave it. However, when you do have to replace it, take care: the water line on that boiler is quite high off the floor, and you must match that water line with any new boiler — which may put it on something of a pedestal. Do it.

If it is set up right the traps on the emitters should never close. The traps on the mains have to be working. The traps on the returns may or may not close depending on exactly how the return trap works.

It looks like very little has been done to this system since it was installed so things that don't work are likely parts that need to be serviced rather than things that are wrong.

A furtherthouht on traps. Up there I said "replace them". I should have said "replace the innards". They're all replaceable, and it is much better to just do the innards rather than replacing the whole thing. A lot easier, too.

I'm not sure what these are. If they are a vent that has been sealed up with stucco or if they are even part of the heating system.

This is only true to a point - the original traps in my house (Illinois Series G) had a diaphragm innard that allowed it to operate with the outlet vertical or horizontal. I discovered that the replacement only allows for vertical outlets - I have a radiator in my bathroom I need to get a new horizontal 90-degree angle trap for still.

A little bounce (about an inch or less) is fine.

Might want to open the fill valve and bring it up to the mark to make sure all that works before you do the blow down.

The returns have to vent somehow because that is how the radiators vent. It likely is through one of those devices at the boiler.

This is a heat exchanger for the water heater which looks like it has been abandoned.

That radiator! That trough on the top was for water. Probably did have a connection at one time to a water supply and just maybe a drain. The idea was to have it provide extra humidity to the room.

Ingenious…