Upstairs steam radiators cold but intake is warm

[Lily left the valley]

So tonight I discovered our first Old House Fix that jumped to the front of the "To Do" list.

The first time I went upstairs to take some pictures, I noticed quite a temperature change, but I foolishly thought it was due to the fact that the first room to the left that I was going into doesn't have a radiator.

Then I realized none of the other three room's radiators were warm either. When I gently felt the pipe coming out of the floor, it was definitely warm. I fiddled with the "open/close" a few turns carefully, and all were obviously turned to "open", but nothing immediate seemed to happen from opening them a bit more. In particular, no hiss out of the vent on the other side.

So I went back downstairs, and started counting how many turns to close the ones down there before turning them back again. They are ALL at different open count turns. (the two counts I recall off hand is one was 4 turns and one 7) I also started to notice something else. We have no less than four different types of release valves on them unless I missed a type when I ran around trying to catalog them all. Here they are, in no particular order:
This variant has the adjustor screw on top of the loosely fitting cap with a gap, if you will.

This one has a horizontally sliding panel you can adjust with a tiny nub sticking out of it.

This one appears to be the most modern, with clear and easy to read numbers at the base. I didn't seem to be able to hand turn it though, and I'm not sure if that's due to build up or a screw underneath I didn't think to look for at the time.

I could not find a discernable adjustor on these. There is a simple pin hole on top.

Upstairs there were two I remember clearly. In the east bedroom, it's the first variant above. In the north bedroom, it's the second. I cannot recall which that bathroom had, but from another pic of it I took showing how much smaller it was overall, it looks to also be the second type.

I didn't want to open these much more just in case I went overboard, and would come back the next day only to find a huge mess on my hands. I did turn the top screw a quarter turn more open on the east bedroom just to see if that made a difference, and am realizing now I never turned it back the same. Still, no hiss, no warm most air could be felt by it, no nothing.

I was going to try to do some research tonight, but I am pooped. I also have a lot to do tomorrow...erm...today. So I'll try to get some research done over breakfast.

If any of our Wise in the Ways of Water folks can offer some advice or suggestions, I'm all ears. These are all single pipe steam radiators. I also just remembered it felt really, really warm downstairs compared to upstairs, and the digital thermostat (in the dining room way too close to the side door that has no screen/storm, but is a newer door) was only set to 61°F. Now, I was wearing a turtleneck, plus a turtleneck sweater with a thinner zip sweatshirt over that because I walked to the house and the temp outside has dropped back down to near freezing again. (I just checked now, at 2:48 am and the "local" page says 26°F outside.) So it's possible that the first floor was a lot less warm than I was feeling, and upstairs, much more cold.

I did check the pipes in the 1/2 bath, and could not see any possible signs of icing or recent freezing type issues. (I've had to deal with frozen pipes in the past.)

It seems to me that the steam is getting upstairs, it's just not heating the radiators. I'm not sure if this is because:
1) the valves are not open enough
2) there's some sort of buildup on all on that floor (not as likely, I think)
3) if they were shut off longer since "heat goes up", maybe I need to make them lean a bit more towards the single intake/return pipe so any cold condensate can better drain? I honestly didn't think to check their tilt angle when I was there.

As far as I know, there is only one zone in the home. I will try to look at the boiler and poke around on the second floor in better light to see if I missed something on that score.



Ok, I did a quick search because it doesn't take too long. One thing I want to mention is it is not only cold outside, but we have had high winds for going on three days. Also, our attic lacks insulation. From what I found, those factors might not be helping matters.

I did find some basics to check on inspectipedia, and a rough of both where my water gauge and pressure should be. I wrote all that down and will check when I get over there later today. I'll also be taking a level. I have no idea if I have shims in a box at this point, so I might have to make some.

I do recall our water level was a bit low during the inspection. Our inspector was wise to remind me not to dump too much cold water in to make up the difference, especially if the boiler is running close to 100.

Is the same true if the tilt is off on one or more rads? Should I not immediately adjust them if so?

I'm not going to change anything when I go back unless the water level is dead low and I'll mind that extra careful as I refill. Otherwise, I'm just going to take notes. I have some experience with boilers (and ones much older than ours), but not that much.

[CS in Low Hud]

So.. the way single pipe steam rads work is that the cold air in the rad is displaced - slowly - by being pushed out of the holes in the vents by the warm air (steam) in the pipe. Once the steam hits the valve, the valve should close down. If the cold air CAN'T leave, for some reason, then the warm air can't enter. It sounds like your vents need to be replaced. Usually they get plugged up and don't allow the steam to enter the rad, but sometimes the get stuck open, and hiss or leak as the steam escapes. They do have a life-span (seems to me they are good for about a decade).

The good news is that they are not terribly expensive, and most good hardware stores will carry them. The old ones unscrew (be sure your system is OFF and cool for a while - no live steam!), and the new ones just screw right in (finger-tight only, don't use a wrench, though you might need one to get the old vents off ).

They come in different hole sizes. The bigger the hole, the faster the rad will heat and the longer it will stay hot. So, I have found, in general, vents that have adjustable hole-sizes are helpful for balancing the system. Your first three pictures are all variants of this kind of adjustable valve. Usually, the smaller the room, the smaller the hole size, but a tiled bathroom will require more "oomph" than a small bedroom, for example... as will rads that have the furthest run from the boiler (since more air must be displaced before those will heat).

Speaking of which...there is another valve to replace in your basement, though. Usually the steam pipe rises up out of the boiler, and runs around the ceiling, gradually increasing in height until the last riser leaves to go up into the house. At that point there is probably a smaller return pipe for condensate heading back to the boiler, AND a valve for that main line. If that valve is plugged up, steam will have difficulty reaching the last risers (and all the rads those feed), so you need to replace that one as well.

If you can stand it, you might want to wait until the heating season is over to make these replacements. We're almost there!

Chris

[nhguy]

We had steam radiators in our old colonial a couple of houses ago. I had a book on how to make steam systems efficient, the two things we did was replace the valves on the ends of each radiator with the adjustable type. It had a little white knob at the bottom with numbers just like in one of your pictures. They worked great and are still in service 11 years later. We also replaced the air valves on the pipes in the basement, they were dated 1928. I had to heat them with a torch to get them off, but in the next heating season I noticed they were working as before they didn't let any steam out. It does sound like your air valves upstairs may be clogged and need replacement and or cleaning. Good Luck.

[Lily left the valley]

Thanks, Chris and njguy.

The good news is that when we went over there today, all three radiators upstairs are working. They're still not as warm as the one downstairs, but they are definitely working, and the air temperature was nowhere near as extreme between up and down. Sean guessed that after they accepted our bid, they likely had closed down the upstairs radiators. Our first "final" walk through was about two weeks ago, so even if they re-opened them then, if they'd been shut off for around three months, it kinda makes sense to me that it would take the system some time to rebalance itself.

One interesting thing I noticed with the boiler is that the water level gauge was actually roughly an inch and change below the line marked. As I walked around to re-orient myself with it, the boiler cycled back up.

I started taking some pictures, and when I came back around to that side of the boiler, I noticed the water level had shot up and actually sort of pulsed between just below the mark and quite a bit above it (though not to the very top of the gauge).

Fortunately, the manuals for all the bits of the boiler at there, so I have that at least. The pictures of the boiler I took while there tonight can be seen here.

Here's the water gauge when the boiler was running, showing the pulse at its peak. The magic marker on the gauge is the "level marker" I'm referring to. Unfortunately, I took the shot just a shade low, so you can't see the top of the gauge, but if you could, you'd see there isn't much breathing room there when the pulsing water hits the high mark. The top of the glass part of the gauge really isn't much more above where the photo ends. Maybe an inch.

[nhguy]

You want the water level to be in the middle or ever so slightly higher than the mid point. The water level does jump when the water is boiling in the steam boiler as I recall. It seems to me the upstairs radiators never got as hot as the ones downstairs, but it's been a decade since we lived in that house.

[Lily left the valley]

You want the water level to be in the middle or ever so slightly higher than the mid point. The water level does jump when the water is boiling in the steam boiler as I recall. It seems to me the upstairs radiators never got as hot as the ones downstairs, but it's been a decade since we lived in that house.

Great to know, nhguy. It's been a long time since I've lived with a steam system myself, so it's almost like relearning boilers in a way. Dealt with the hot water systems for so long, the steam quirks feel like all new things to learn again.

Now that the heat has been on consistently, the upstairs radiators seems to be working just as well as downstairs. We still have some knocking when the system kicks on, but it doesn't last long so I'm not overly worried about that for now.

I'm thrilled, actually, that we managed to get a house with a steam system. It's my favorite overall house heat. What's kind of fun too is that I've noticed all our various types of steam release valves have their own hisses, depending on the model. So I'm already learning from ear which ones are filling and settling in when the cycle kicks in. Although we're slowly filling the house up with our stuff, there's still a lot of echo right now, so it's easy to hear them all almost anywhere in the house, save the cellar.