Nursery room radiator cold (With PICS) UPDATE

KC_Jones

I'm pretty sure that was posted already. See where I circled.

New England SteamWorks

Sorry, missed that. What about the other return?

Fred

There should be a vent on each main. It looks like you only have one main off of the boiler but it may branch off somewhere in the basement. That branch still needs a vent.
If I'm interpreting the piping correctly, behind your boiler, it looks like your equalizer, the pipe that comes off of the end of your header and drops down to the floor actually ties into your wet returns and not directly into the boiler. If that's the case, the steam/pressure would be pushing against the returning condensate and not against the water/pressure in the boiler. How much does the water level in your boiler drop during a heating cycle? I would think condensate would stack in the returns until the cycle ends and then rush back into the boiler.
Anyway back to your radiator issue. I suspect if you get Main vents installed somewhere after the last radiator run out, on each main/branch, you will likely fix the radiator issue. Steam probably can't get to that radiator because it can't evacuate or even compress the air in those mains enough for steam to get to that radiator run-out.

MilanD

Just to say it, depending what the riser to that last rad looks like, you may be able to add a main vent just in front of that radiator. Something like the attached. It'll be easier to do than breaking into the main the way it's right now.

https://www.amazon.com/photos/share/MhyOdhuNbEbg3AQVQAUW4aybJI0rKwtXIwjT9OJr6qJ

grye

This is where the return comes from @New England SteamWorks

grye

Thanks all.

It seems like if I shut down certain radiators on the first floor I get heat to the one on the second.

This seems to be a band aid fix. I still can’t find the main vent. Would adding an adjustable vent on the problem radiator be able to adjust to pull more heat?

Fred

You need to have someone find a good location to install a main vent. That area, in your picture, right before the return drops to the floor would be ideal. Until you get main vents installed, you really can't balance your radiators. Closing off other radiators is not the best solution as with each one you close, in addition to the discomfort, in those rooms, you make the boiler more and more over-sized and it will begin to short cycle.
One other thing to check, look at the boiler plate and it should tell you the "Sq. Ft. Steam" what is that number? Then let's try to calculate your connected radiation. It's rare but possible that the boiler may be too small for the connected radiation.
I say that is a possibility because closing radiators off radiators gives you even less system venting and should compound the problem.

grye

@Fred I’ll check. The entire first floor was renovated before we bought the house an opened up to almost an entire open floor plan from front to back. So there’s four radiators with only a half wall separation. Don’t know if that helps or hurts.

So we think my sister has no main vent at all?

MilanD

It looks like you don't have a main vent. I would say this is why your system heats unevenly. Basically system vents through all the rads and fills them one at a time. When you close another radiator to make this last one heat, you are changing this balance. Also, as all the rads early on the main (closer to the boiler) condense steam into water, they will start making micro vacuums and continue "stealing" steam from the main and other rads. Then only way around it as is currently is to keep high operating pressure and waste fuel until all other rooms are satisfied and blazing hot so excess steam can now go to that last rad.

So, I would suggest you add another vent to that last rad, or add a main vent like the pics I showed earlier, just before that last rad in the system. This would require only removing the valve from the last riser and repiping slightly to add a vent port. With this setup you would have both created a main venting point and would be directing the steam to that last rad first, at the same time driving steam to fill the entire main first and fast, and then slowly fill the rads. And here's the fun part - the cost would be minimal as this would be a pretty easy diy project needing only a few fittings and short nipples, it would require no cutting or drilling, and would be a great excuse to purchase some pipe wrenches.

grye

@MilanD @Fred

This radiator with the issue isn’t at the end, it’s actually at the beginning, just on the second floor.
Boiler is on the rear west side of the house, the radiator is on the rear east side.

If I turn off other radiators, I get heat to it. Or, if i increase the temp significantly, I get heat.

Would this still be a main vent issue?

EBEBRATT-Ed

Steam takes the path of least resistance to each radiator. A radiator closest to the boiler could have higher resistance to steam flow. Usually the farthest radiators are the toughest to heat.

It's all about:
Proper venting for radiators and mains

piping with no dips or sags and properly sized

a boiler that can make enough steam to fill the piping and radiators

Steam must be dry

Fred

@grye , yes, it could still be a main venting issue. As @EBEBRATT-Ed said above, steam will take the path of least resistance. As the steam moves through the main, it will take that path. If the mains are properly vented, it will fill the mains and they feed into the radiator run outs, taking the next path of least resistance, depending on the size of the radiators and the vents on them. Faster vents on bigger radiators will fill first if the system isn't properly balanced. However, to do that balancing, you have to have very good venting on the mains and the main has to be filled with steam and those main vents closed.

grye

Would an adjustable steam vent on this problem radiator pull more steam (And more heat) to the radiator?

BobC

It depends on what the other radiators have on them for vents, the steam will usually go to the faster vented radiators first. It's usually best to start with all small vents and then increase the venting on radiators that aren't heating right. Don't go from a #4 to a D, increase venting incrementally.

What kind of vents are on the other radiators. If you want to experiment you could try the Maid - Mist 5L vents, they come with 5 different orifices that you can change by just changing the orifice itself, that saves wear and tear on the radiator port threads. They are available on amazon at a good price

Bob

KC_Jones

I think we need to understand where you are at. Without main venting your expectations should be relatively low in my opinion. If you want it to have any chance of working you need the main vents. It sounds like you are resisting that concept?

The system would have probably worked well on coal since it was low and slow. Basically lazily made steam all day long. Now it's on and off at full capacity only, so you need those main vents.

EBEBRATT-Ed

Venting is important. Could be an underfired or too small a boiler but not likely. Regardless venting needs fixing first

Steamhead

Also, look closely at the piping as it comes out of the boiler. It looks like it reduces in size twice.

If this Williamson boiler is the same as the Weil-McLain SGO, the steam outlet is 2-1/2". The bell reducer right above the boiler looks like it goes down one size, to 2".

When the pipe gets up to the header, it looks like it reduces again, maybe to 1-1/2"?

Finally when the pipe gets to the steam main, it increases in size. Not sure whether it goes back to 2" or 2-1/2".

Main venting is important- it's how we've reduced fuel consumption on some systems by a third- but if the piping around the boiler is too small it won't deliver enough steam, and what there is will have so much water in it that it won't heat well.

Jamie Hall

Oh dear. I wasn't looking at the near boiler piping. My error. If it really is reducing and then expanding as @Steamhead noticed, then you will have trouble getting heat out of the system. Saturated steam is weird stuff, and when you hit a reduction and then an expansion, it doesn't just speed up and slow down like water or air -- it just (to put it colloquially!) says the heck with it and condenses, which is not what you want at all.

grye

@Jamie Hall @Steamhead @Fred @EBEBRATT-Ed

I take it from Jamie’s “oh dear” that steamhead uncovered something.

I will say, preliminarily, I put an adjustable vent on full vent on the radiator in question and it seems to be working. For now anyway. I’ll keep an eye on it.

Is this reduction/expansion an issue? Maybe for efficiency reasons? The boiler is new, built two years ago when the house was gutted and renovated....why would they do that?

KC_Jones

Why would they do that? For the same reason they didn't install proper main venting, the heating guy doesn't know steam.

Did you mention your location? We may know a competent steam contractor in your area.

grye

Yonkers, NY.

If the piping right above the boiler just needs to be swapped with the proper size before the main, that doesn’t seem like a big job at all, is it?

Fred

@grye , you need to measure the diameter or circumference of the riser, the header and the main above that boiler. When I look at the first post and the first set of pictures, the only reduction I see in pipe size is out of the boiler, from 2.5" to 2". The rest looks like 2" pipe to me. I don't see any other reducing elbows or fittings on that piping except for the one out of the boiler and the one that turns down into your equalizer (which is normally reduced) While it would have been ideal for the installer to have used the full size out of the boiler, I don't think that is causing your problem, especially with the height you have on the header.
Why did they reduce that pipe out of the boiler? Because the installer wanted to use the rest of the original piping on the header and equalizer which, unless I'm not seeing something looks fine to me. I wish he would have used the full size tapping out of the boiler but, it is what it is. We certainly have seen much worse near boiler piping.
I would suggest you insulate all the steam pipes, in the basement. That will help steam get to all the radiators.

Jamie Hall

@grye -- if it just reduces, while it's not great it's OK. Leave it. It's if it reduces but then expands again that it could be a problem. I can't judge well from the photos.

Fred

Insulate the pipes in the basement and ditch that Cyclegard low water cut off and replace it with a Safgard and I bet you problem with that nursery radiator will disappear. The Cyclegard LWCO stops the boiler every few minutes, during a heating cycle and keeps it off long enough to let the water stabilize to check the water level. That constantly interrupts the production and flow of steam. Just not a good design approach. The Safgard does not do that.
The probes on both the Cyclegard and the Safgard are the same so you don't have to lower the water level in the boiler to switch them out.

EBEBRATT-Ed

The original installer like many won't use 2 1/2" pipe or larger because they want to get the job done and don't have the equipment to thread 2 1/2" or larger on the job. Most can't weld so that's out. And even though they could probably make it up with nipples and couplings or find a supply house that can thread the larger sizes.......that's just too much work for them.

Even if they could read they would still use the smaller pipe for that reason. Mega press and Propress are rated for 15 lb steam but I wouldn't use it on steam although I suppose it would be ok for condensate but costs too much for me anyhow.

All steam boilers except the smallest sizes usually require 2 1/2" or larger pipe.