Steam system building pressure too quickly. No vents in sight.

Chartline

Good evening,

I have a complex situation and I can't for the life of me find anyone in CT that is knowledgeable in steam systems. Apparently there is a guy in RI and a guy in MA but neither one of them will come to CT for me.

I have a 1930s 2-pipe steam system. I have 17 cast iron radators on 3 levels. One t-stat therefore, one zone. Currently, I cannot get steam though my system. The t-stat calls. The boiler fires. BUT the system builds pressure much MUCH too quickly. Due to the pressure, the pressuretrol shuts the boiler down within 3 to 5 minutes after firing. The Pressure trol currently set to 1 PSI. At first we thought the pressure trol was bad. We replaced it. No change. I now belive there is air, water, or debris, or all 3 in the pipes (most likely air in my opinion). 2 of the 17 rads are luke warm. The rest are cold. Some of the mains are hot but the steam stops before it gets to the rads. The returns and and most of the rads are ice cold.

I bought this house 7 years ago. The first winter in the house, the oil boiler over heated and the body cracked. I decided that if I was going to replace the boiler, I was going to bring natural gas in from the street and I did. At that time there was 19 radators in the house. 17 steam rads and 2 condensate rads. I can't recall exactly what the original set up was however, I belive there must have been a circulator pump that sent the steam condensate to two radators in the basement level of my home. In 2017 the contractor that installed the new gas fired boiler must have decided that the condensate radators and pump etc. was too complicated so he eliminated the pump and deleted the two condensate radators. I believe that deleting the pump may have been the first misstep…

At this time (2017) the contractor also installed an auto filler with a digital gallon counter. For the first 5 winters, the system worked decent meaning most (not all) of the rads in the house got hot and we had heat however, we noticed we were going through way too much water. Many many gallons of water. In 2022 I poured Gypcrete on the basement floor as part of an ulrelated project. The Gypcrete dried faster in a line running back to the boiler room. This is how I discovered that there was an under slab wet return that had been cut and capped on the boiler room side of the leak prior to me purchasing the house. We surmised that the under slab return was leaking and this is why I was losing so much water. I thought it would be a good idea to replace the under slab return so we cut up the concrete slab and replaced the 3/4“ return line and tied the return back into the area of the Hartford loop. I belive this is when the real problems started!…

I should tell you that we cannot locate any steam traps or air vents. Zero! None! I could be wrong, as I have zero previous experience with steam systems however, is it possible that the condensate pump had an air vent on it and elemiating the pump also eliminated the air vent? And is is also possible that eleimating the pump (and possible air vent) wasn't an immediate problem in 2017 becuse the hole in the under slab pipe was acting as a vent? I can tell you that the real problem started in 2022 when we repaired the under slab wet return. Around that time the system also flooded with water and water got up into the steam pipes.

It seems to me that the steam can't work through the system becuse the pipes are blocked with air and the air can't get out. It's like blowing into a bottle. Can I, and should I, add new main vents to my system? Any advice you can give me would be greatly appreciated becuase I can't find anyone in the area that knows much about steam systems. At this point I know more than the techs and that's sad becuse I'm just a homeowner and all of my knowledge, which is very little, comes from reading on the internet.

It's getting cold in CT and my wife is getting hot and not in a good way. Thank you in advance for any advise you can provide.

-Cold Cory in CT

Steamhead

@Chartline , post some pics of the boiler, the piping around the boiler, and some radiators that do not have covers. Let's see what you have.

Chartline

Chartline

I have a Utica boiler. Boiler seems to work fine. The pipes in the boiler room are spaghetti. Once they leave the boiler room they are difficult or impossible to trace. The house is mostly brick and plaster with metal lath. I have 2 horizontal rads on the ceiling in the basement level. One normal rad mounted high on the wall in the basement. The rest of the rads on the main level and upper level are in the wall and have covers on Them. Again, I can find an air vent anywhere. Not on the rads. Not in the boiler room. No where.

Steamhead

That "covered radiator" is called a "convector". Can you take the cover off so we can see what's inside?

From what I can tell, the air from the radiators/convectors is supposed to come back to the boiler room through the overhead ("dry") return lines. There should be a large central air vent where those lines come together in the boiler room. If there is not, someone removed it- likely the same guy who did such a horrible near-boiler piping job.

Chartline

Steamhead,

First, thank you for taking the time to help me. I took the cover off of one of the smaller ones. As you can see it basically a rad behind a metal plate. The supply pipes enters top right on this one. There is a valve but no handle. I never really touched the valves but I did confirm they are all open. This rad has 7 sections. Most in my house are larger. Some have 20 sections. The pipe exits bottom left on this one.

Chartline

109A_5

Hello Chartline,

No vents hiding in an attic or crawl space ? Yes it does sound like with that pressure issue the steam can't push the air out of the system so the pressure just builds quickly, the steam can't get to the radiators, as you said the air has no where to go.

Maybe not a perfect fix or optimum but a quick one (it's heating season), I would 'Tee' into the pipe at each Yellow arrow and put in a main vent. Also (not pictured) where the far end of the underground copper return meets the old system black pipe I would put a vent there too. You could do just one return as a test of that section of the system, see if the steam gets to the radiators better, however with only a fraction of the system venting it still will trip out on pressure.

No swing joints on that boiler's header. May have helped contribute to the old boilers failure.

Jamie Hall

The idea of temporary vents on some of the mains and, especially, on pipes which can be clearly identified as dry returns does have a good deal of merit — as a relatively inexpensive and partial fix.

However, from what I can see in the pictures, I am thinking that this was, once, a vapour — very low pressure — system, probably with just one main venting location at or near the boiler. It may not even have had a vent device there; some systems were simply open to the atmosphere (or, not uncommonly, the chimney) at that location. There may have been special devices on the radiator outlets — I can't see that one outlet sufficiently clearly to tell — or control may have been with orifices.

One way or another, though, it is quite clear that there has been at least one stage, if not several, of misguided revisions to the system (the latest being that near boiler piping…). This makes life much more interesting. What needs to happen is that someone needs to go through the entire system, thinking of it as a coherent system, and determine what was original and what has been added, changed — or removed! — over the years. Then formulate a plan to redo what needs redoing to make it functional again.

Steam systems are not, fundamentally, either difficult or mysterious. You need a boiler, of course, to create steam. You need near boiler piping to ensure that the steam going to the system is reasonably dry — that it has shed enough of the carryover from the boiling to be steam, not a water/steam mix. You need piping to convey that steam to the radiators. That piping needs to be able to drain any condensate to somewhere. The air also needs to get out of that piping. Then you need the radiators, of course, and some means to ensure that either just the right amount of steam gets in or, if extra steam can get in that it can't get out again — but at the same time that air and condensate in the radiator can get out. Then you need another set of piping to carry that condensate back to the boiler and the air to a place where it can escape. Often there will be a third set of piping which picks up condensate from various locations and carries that back.

That's it.

I probably would start with the radiators and figure out, for each one, how the steam gets to it and how the air and water get out of it, just locally. Then I would look at the pipes feeding the radiator and figure out the same thing. Always working back towards the boiler.

Patience. And if you hit odd bits of piping out in the wilderness somewhere, or unexplained gadgets, how about a photo for us to think about?

delcrossv

Isn't there a pro on here that services Ct?

Rationalizing a bodged vapor system isn't a trivial task.

Steamhead

Try @Charlie from wmass .

Charlie from wmass

Doesn't look familiar. Where in CT are you?

Chartline

@delcrossv @Steamhead @Charlie from wmass @Jamie Hall

Charlie,

I am in Meriden, CT. Almost dead center of the state.

We have been in contact 2 or 3 times over the last 2 years. We have spoken on the phone and we texted as well. I understand that you are extremely busy and unfortunately for me, you have not had an opportunity to come to central Connecticut. If you could find the time, I would greatly appreciate it. I have been struggling with this situation for 2 winters now and entering the 3rd. I can't find anyone in the state that has the knowledge to correct this issue. @JohnNY called me this morning after I reached out to him.

What Jamie said above about a vapour — very low pressure — system... may not even have had a vent device there; some systems were simply open to the atmosphere" makes sence to me. I think that's part of the reason why local, non-experts don't understand the system.

I can tell you that that SEVERAL misguided revisions have been made over the years. I belive the system must be fully assessed by a true expert.

JohnNY

I’m looking forward to meeting with you.
Thanks for calling. I’ll get your system straightened out.

Jamie Hall

I'll be very interested in what you find! Keep us posted, @JohnNY and @Chartline !

Charlie from wmass

You are in good hands now.

JohnNY

Thanks, @Jamie Hall and @Charlie from wmass. I'd love to see this system working as well as I'm certain it once was. Will report back.