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Water coming out of every wall: when steam radiators go wrong

sharing my husband's explanation of today's family chaos here, in case some of you pros have ideas on what happened --

Hi folks, sharing a situation I had today, hoping the hivemind has some advice on what to do next.

Cast of Characters:

HOUSE: Built in 1905, used for short-term rentals. The house is three stories tall (+ a basement) heated with steam radiators, and the boiler is old (30? 40 years old?) but was serviced recently (by the same company that has always serviced it!) and was supposed to be in "good working order."
RENTERS: Two groups of out-of-towners from the south, staying at the house for about a week. Set the thermostat a balmy 84 degrees.
SPOUSE: My beautiful wife, who manages the rental property.
CLEANER: Our amazing cleaner, who cleans the house between guests.
Setting: The story takes place in Chicago, IL, today. It has been bitter cold the past week, with lows of -8 and highs of 3.


The cleaner showed up at the house today at around 9am to do her stuff. She notices that there is some discoloration in the ceiling of a bedroom on the second floor. She calls my wife to let her know.

About 1pm, she hears... noises coming from one of the bedroom. She goes to investigate and finds water streaming down the wall AND water gushing out of the valve of one of the steam radiators. She panics and runs downstairs to fetch a bucket, and notices thatt:

a. There is water streaming down the walls of basically every room
b. About half the radiators in the first and second floors are gushing water like the one she had noticed. c. The water is so hot it's causing the paint to peel.

At this point she panics and calls my wife, who then panics and calls me. I then panic and call nobody.

Meanwhile, the cleaner is running from room to room, placing buckets and trash cans and bags under the radiators, waiting for them to fill with water and then emptying them.

When my wife shows up she finds her running from bucket to bucket emptying them, but she can't keep up. A 3 gallon bucket get filled in about 3 minutes.

My wife calls me and she turns off the boiler and the water main. Some of the radiators stop leaking but the one in the first floor closest to the boiler spews water for a solid half hour.

Wife calls the boiler repair company, which offers 24/7 emergency service. They cannot come for 3 days. "Everyone is having trouble" they say. Oh, and when they come on Friday it will be at emergency service rates.

She then calls every heating service company in the city. "Sorry, no new clients. Everyone needs help right now."

When I finally show up, about two hours later, I go straight to the boiler. I suggest to my wife that we turn the water main back on, because what could it have to do with this, right? She then tells me that she had tried to turn it back on before, but it had caused the gushing in one of the radiators. I proceed to tell her that makes no sense. She rolls her eyes.

Next, I notice that the boiler sight glass is completely full. "Hmm, that's odd". I start to drain the boiler and... nothing happens. The sight glass is still completely full. I let it drain. And drain. And drain. No movement in the sight glass.

After 45 minutes, wife peeks her head down into the basement: "hey, what did you do? the radiator is making noises".

Finally, after about an hour and a half, the water level in the sight glass starts to drop. After it drops most of the way, I turn the water main back on.... and the water in the sight glass creeps up again, filling it completely.

Lastly, I close the inlet valve to the boiler so that water can't come in, and drain it until the sight glass is about 3/4 full. I try to turn the boiler on "to see what happens."

Nothing happens. The boiler won't turn on.

I have some mini-split systems in the house, which I have set to heat-pump mode. Every faucet is set to trickle. I hope the minisplits have enough heating capacity to keep the house above freezing until we can solve the problem. I am deathly scared every pipe in the house will freeze.


This is what I think happened. At some point in the past day(s), the water feeder valve got stuck in the open position for some reason. The boiler then overfilled, and boiling water started filling the steam lines and the radiators. Up through the first two floors. Each radiator that got filled then started spewing water. Also, there must be some sort of leaks in the lines themselves because there is water damage below radiators that weren't spewing.

The boiler repair guy can't come until Friday, two days from now. I have guests scheduled to arrive next Friday, ten days from now.

So, hivemind... questions:

What should I do?
I am hoping that simply fixing the feeder valve will solve the problem, and that once there is steam (and not boiling water) going through the system everything will be fine. Is this... stupidly optimistic?
There are leaks in the 2nd floor ceiling, even though the 3rd floor radiators weren't spewing water. So obviously this means there is a leak somewhere in the steam line. Is it possible that once it's just steam and not hot water, things will be fine? Or should I start breaking up the (plaster) ceilings to find the leak?
Should I involve my insurance company?
It's possible the boiler repair guy is just a...boiler repair guy. Would he know about the entire system or should I also involve a plumber? Or a pipe fitter? Who the heck knows how to install residential steam lines these days?
How screwed are we?
If I'm right, when why did only some radiators fill up with water and not all of them?

Happy new year, thanks for reading.

Condensing in Chicago


  • Gordy
    Gordy Member Posts: 9,514
    Repost in the steam heating section. Sounds like the feeder stuck open.
  • Fred
    Fred Member Posts: 8,518
    Clearly the auto water feeder is stuck open, as you suspect. Is there a hot water coil in the boiler to supply hot water for the house? If so, that could have sprung a leak, internal to the boiler and filled it. I'm assuming this is a one pipe system, with vents on the side of each radiator? The water filled the system and ran out of the radiator vents. It hadn't yet reached the third floor so they didn't leak.
    Given this is the case, the main and radiator vents will need to be washed out to ensure they close properly and don't have crud in them that prevents them from properly seating. Boiler probably didn't re-fire because, being filled with water the Presssuretrol probably prevented it from re-firing as the pressure would have been over the set limit.
  • Jamie Hall
    Jamie Hall Member Posts: 18,977
    Did any of the controls get wet? If so, they really need to be replaced.

    That said. The boiler didn't turn on. Was the thermostat set to call for heat? I know that sounds obvious, but in the stress of the moment we all overlook obvious things...

    Is the boiler getting power? Check the circuit breaker or fuse (may be more than one). Check the emergency switch. Again, there may be more than one.

    Then there are safeties on a boiler: the pressuretrol or pressuretrols and the low water cut off or cut offs. Are any of those manual reset?

    The pressuretrol or pressuretrols may well have gotten damaged from the excess pressure of that much water. They aren't made to take that. Are they the microswitch variety? See if they are all closed properly so the boiler can fire -- turn off the power, take off the cover, and use a multimeter to make sure the switches are closed. If they have been damaged and are stuck open, they should be replaced. Check also that the pigtails going to them, and the openings in the bottom of them, are clear.

    If all that checks out, try starting the boiler again. Does it even try to fire, or does it just sit there?

    Note that if you know exactly what you are doing you can bypass all of the safeties to see if the burner will fire. I say again, exactly. Further, a boiler must never be run for any length of time with a safety bypassed, and even then it must be attended with someone right handy on the power switch in case something goes amiss.

    If you can get the boiler to fire, you're starting. Now -- you may well find that some or all of the steam vents, particularly on the lower floors, have been damaged and either won't open or won't close. If so, you will need to replace them. You will probably also find that the system hammers and bangs like crazy because of trapped water in various pipes, and some radiators may heat poorly or not at all. Once you get steam up, this will go away (assuming it didn't do it before) -- but it may take a while.

    Meanwhile, leave that auto fill off, with the valves to it closed, until you get a chance to have it repaired (maybe) or replaced (much more likely). What controls it? If it's a float type control, that may have stuck and you should clean -- and possibly replace -- that, too.

    Your insurance may or may not cover some of the loss. You'll need to talk to your agent about that.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    EBEBRATT-Ed Member Posts: 12,023
    Chances are your low water cutoff is defective. Can't tell for sure but in many cases the low water cutoff also operates the make up water to the boiler. If the LWCO is defective, stuck, hole in the float etc. it would cause the boiler not to run and also turn on the automatic water feeder even if the boiler does not need water. This would cause the water to overfill.

    Anyone working in the heating industry SHOULD???? plumber, pipefitter be able to fix this but

    a qualified service technician would be best to troubleshoot this problem
  • Steamhead
    Steamhead Member Posts: 15,350
    @The Steam Whisperer is in Chicago.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Neild5
    Neild5 Member Posts: 135
    @The Steam Whisperer (Formerly Boilerpro) is the place to call. 773 779 5740
  • wildrage
    wildrage Member Posts: 185
    edited January 2018
    Man, I really feel for you. Especially in this crazy weather. My autofeed stuck open about 2 months ago, and I happened to be home. The water never made it to the 1st floor, but I had to drain over 50 gallons out of the boiler, and it scared the crap out of me. I have since disabled the autofeed and will address it in the spring. Unrelated, I found that the water pressure reducer for my house was defective, and pumping 100psi water in from the city. I read somewhere that this has been known to cause the auto feed valves to stick open...something you might want to double check, when you get this all resolved. A water pressure gauge can easily be had off of Amazon for about $10.

    In my opinion, as long as you service the boiler every year, and ensure that the LWCO is working, the benefits of the auto feed are not worth the potential for disaster. Can you imagine if the house was vacant for 2 weeks and all of this happened?

    I will be purchasing one of those metered autofeed units that stop after a set volume and have a meter on them so you can see how much makeup water has been fed.

    As for the leaks in the walls below radiators that didn't leak - I'm not sure. I had a pinhole leak in a radiator pipe, and I knew about it immediately (with just steam), so I'd be surprised if it only just leaked now. Are you sure no water made it to the 3rd floor? Like out the packing nut on the valve? I could definitely imagine nobody noticing some steam leaking from it, but water being able to come out pretty well, and just going straight down through the floorboard without creating much of a mess. It seems weird that the water didn't make it to the radiator, but still leaked through the wall...like - there's probably only a few gallons of difference of water volume in the riser to make it to the radiator....what are the odds? Maybe just wishful thinking on my part.

    Oh, and I've read that the presural can get water logged after flooding, perhaps that is preventing the restart?

    Best of luck to you! You came to the right place for advice.
  • Jamie Hall
    Jamie Hall Member Posts: 18,977
    Steamhead said:

    @The Steam Whisperer is in Chicago.

    Thank you! I have very high regard for him, but I hadn't heard from him for awhile and I couldn't remember the handle. He could get all this straight.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Thanks everyone. You people are amazing.

    The system is indeed one-pipe, and none of the controls got wet so that's good. @Jamie Hall the first time I tried to turn on the boiler the thermostat was indeed not set up for heat so you're right about missing the obvious :)

    Unfortunately, I'm not confident with how to to reset the pressuretrol--let alone try to turn on the boiler with safeties off. I'll have to wait for a specialist.

    The system is very old, and the water is very "gunky". I let about a quart out every week from the low water floater (per the previous owner's instructions) and it always comes out full of rust and sediment.

    @wildrage i really hope you're right about water leaking out of the packing nut (or similar) instead of in the wall. It's entirely possible, if hard to tell. It's funny--I thought that having the autofeed system would have made things less likely to break (as i'm sure, in a way, they do), but i had not considered this failure mode. The house is often empty for a couple weeks at a time, so you're right about the disaster this would have been. In retrospect it seems incredibly lucky that we caught this when we did. A day later and it would have been orders of magnitude more damage to the house; a day earlier and our renters would have had a terrible visit. A week or two and i'm sure the damage would have been in the hundreds of thousands.

    A metered auto feed seems like it should be the default. We'll definitely be looking into it.

    Everyone, thanks for the recommendation about @The Steam Whisperer . Unfortunately, I tried to call him when we first purchased the house to inspect the boiler and I heard back then that he didn't take on new clients. I doubt he'd be available--especially with boilers acting up all over the city--but we'll give him a call in any case. Perhaps he'll take the case if he finds it interesting, Dr House style :D
  • Fred
    Fred Member Posts: 8,518
    You can try @Abracadabra too. He's in Chicago. Mostly works the commercial market but he may be able to work you in and he's great. Let's see if he responds to this post.