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Radiator removed, now remaining radiators leak!

We had a radiator into an old laundry room that was leaking steam into the crawl space, so the plumber simply cut the pipe and capped it. Now most of the other radiators are leaking water like crazy from the fittings and out the vents. The system must be out of equilibrium. I did flush it, but that didn't do anything. Does the boiler pressure need to be reduced? Unfortunately, nobody I've talked to has any clue how to fix a steam system or what the settings should be. Boiler is going on and cutting off again. It's a mess!


  • JStar
    JStar Member Posts: 2,752
    edited January 2013

    The pressure should be as low as possible no matter how many radiators are attached.

    Is the system full of water? Too much water?
  • Rod
    Rod Posts: 2,067
    Need more info.

    Hi- Pressure wise, residential steam systems operate at a maximum of 2 PSI.  If you operating pressure is higher than that it needs to reduced. At what pressure is the system operating now? It the boiler water level at the correct height?

    If you don't have them already you might want to look in the Shop section of this website as there are some very good books on steam heating available there.  I would recommend you start out with a book titled "We Got Steam Heat!" It's written for the homeowner new to steam . Here's a link to it:


    I doubt that your problems are caused by the capping of the pipe. It would help it you posted some pictures of your system.  Take pictures of the boiler from different angles and from back far enough so we can see the piping attached to the boiler and where it leads. If we need detail we can zoom in. You might also let us know the make and model of your boiler. This information can usually be found on the placard  attached to the boiler.

    - Rod
  • kcopp
    kcopp Member Posts: 4,392
    where are you....

  • 1913foursquare
    1913foursquare Member Posts: 6
    Too much water?

    Joe, thanks for commenting and much appreciated. I'm not sure how to tell how much water is in the system, but with one-pipe steam I would think there shouldn't be any water in the pipes when it isn't running? If there is in fact too much water, maybe this is why the pipes are leaking at the connections?

    The gauge on the system reads 10 psi when the boiler is running.

    The system has worked OK for years until the radiator was removed Friday.
  • JStar
    JStar Member Posts: 2,752

    I bet the system is overfilled, or operating WAY over the proper pressure. Check the sight glass and see if the water line is visible.
  • Rod
    Rod Posts: 2,067
    Boiler Problems

    Boiler Waterlevel- The waterlevel, when the boiler isn't running, should be approximately half way up the sight glass. If you can give us the make and model number we can probably tell you the exact measurement needed

    Pressure-  10 PSI is way TOO HIgh!   The "cut in" pressure should be 1/2 PSI and the "cut out" pressure 2 PSI. As mentioned before never over a 2 PSI Maximum.

    - Rod
  • 1913foursquare
    1913foursquare Member Posts: 6
    Details on Burnham V-74

    Rod, thanks so much for the tips. The boiler appears to be a Burnham V-74. I've included some pix ... one of the PSI gauge reading about 13 PSI when burner is on.

    I am not sure how to check the water level in the boiler?

    The other pix show where water is running out of radiators.

    The system did work fine until that radiator was removed, so maybe I should ask the plumber to reconnect it!
  • 1913foursquare
    1913foursquare Member Posts: 6
    Sight glass full

    The sight glass on the boiler appears to be full at all times ....
  • JStar
    JStar Member Posts: 2,752
    edited January 2013

    You need to drain the boiler until the water level is a little more than halfway in the glass. It'll be a lot of water!

    The pressure is caused by the overfilled water. Somebody must have left the fill valve open.
  • 1913foursquare
    1913foursquare Member Posts: 6
    Turning it off for the night ....

    Thanks to Joe and Rod for the help. I have a better understanding now of the issues 1) pressure set too much 2) too much water in system.

    I'm not confident about working on or adjusting the boiler myself, so I may be using the Find a Contractor section to look for someone near northeastern Maryland.

    Thanks again and have a great evening!
  • Gordo
    Gordo Member Posts: 852
    Please Consider

    Giving All Steamed Up, Inc a call.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • Rod
    Rod Posts: 2,067
    edited January 2013
    You need a steam pro

    Hi- You need to find out why your boiler is being over filled with water.

    Your boiler's waterline should be 22 5/8 inches vertically from the base of the boiler.

    I would recommend that you get hold of a steampro and have them take a look at your system. You're lucky in that there is an excellent steam pro located close to you in Baltimore. Here's a link to the page in the Find a Contractor section http://www.heatinghelp.com/professional/79/All-Steamed-Up-Inc

    Here is a link where you can download the I& O Manual (Installation &Operating) for you boiler if you don't have a copy already.


    - Rod

    Edit: I posted this reply and see that Gordo has already beat me to it. Frank & Gordo are the steam pros mentioned in the above link. You won't find anyone better. I just wished they lived closer to me!
  • Jamie Hall
    Jamie Hall Member Posts: 22,914
    While you are waiting for All Steamed Up

    to get back to you...

    First thing to do is to identify the pressuretrol on the boiler.  It will, most likely, be a square, probably blue, box with a scale on the front and an adjustment screw on the top.  See what the index on the scale says -- I'll bet it's way over two -- and turn the adjustment screw until the index rests on 2 if it's too high to begin with.  That's for starters.  When a steam system starts to leak everywhere, it is almost always because it is running at too high a pressure; they aren't built for pressure.

    Second thing to do, if you're feeling brave, is to find the gauge glass on the front of the boiler.  You should be able to see the water level in the glass; ideally it woud be about half way up to two thirds of the way up.  If you can't see the water level, you either have way too much water in the boiler or way too little.  Probably way too much (if you had too little, hopefully the low water cut out would work and the system wouldn't run at all).  If it's way too much, see if you can find a handy drain valve somewhere.

    If you post a picture of the pressure controller, and a couple of pictures of the front and side of the boiler, we can help more.

    But these are stop gaps.  Get in touch with All Steamed Up.  He's not inexpensive, but you'll get the money you pay him to get things right back in better operation pretty fast.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • 1913foursquare
    1913foursquare Member Posts: 6
    found PSI setting

    James, thank you for the help ... it is much appreciated. I did find the pressure control and it appears to be set at 8 PSI. The gauge glass seems to be full (or solid water). I'll try resetting the PSI to 2 tomorrow in hopes that it will stop some of the water running out. But I plan on calling in a pro.
  • BobC
    BobC Member Posts: 5,473
    edited January 2013
    Leaking coil

    Does your steam boiler make the domestic hot water for your house? If it does there is a coil inside the boiler that has the hot water running through it and that coil might have a small hole that is leaking water into the boiler. City water is at 60-80PSI so even a tiny hole can overfill a boiler.

    I had a V75 boiler for years so I'm very familiar with them. There is a valve at the base of your boiler and you can drain excess water out of the boiler with that valve, you can attach a washing machine hose to that valve and drain it into a bucket. Just make sure the boiler is off and be ready to handle the water.

    The other item to check is if the fill valve for the boiler (manual or automatic) is leaking. If you feel the pipe below the fill valve it should be the same temperature as the cellar, if it's a lot colder water is getting through the valve. I know my fill valve has to be closed very tightly or it will seep water so check yours just in case.

    If you can get All Steamed Up to look at your system you will be in good hands.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Flooded boiler

    Perhaps the plumber raised the pressure settings on the pressuretrol when he cut out the pipe. It should be lower than 2psi.

    Check the fill valve and make sure it is firmly closed, especially if it is part of an auto-feed system.

    Drain out enough water for the level in the glass tube to be halfway up, or at any markings on the boiler, and mark the level with a clothespin or magic marker. Check whenever the boiler has been off for half an hour, for any deviation. If it still continues to fill, and you have a hot water coil, then that would be the culprit. Daily checking should reveal the symptom, and the cause.--NBC
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