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New to steam - need help with start up

JonnyJonny Member Posts: 1
We have just purchased a house that has been sitting for over a year, unheated, with no homeowners in it. It has a two-pipe steam system. The boiler is made by Utica Boilers, model #. PEG-112AS.

I am a home remodeler and skilled at plumbing, electrical, carpentry, etc, but one thing I have never had to deal with, is steam boiler sytems.

What would you recommend I do\check before we attempt to fire this thing up?

Does the piping even look correct?

ANY suggestions\advice would be greatly appreciated.


  • Start-Up

    Looks like someone came in and removed the water supply line, maybe for scrap copper?

    For a start:

    - Provide a water feed with a valve to the boiler

    - Fill the boiler to the "water line" and make sure it shows up on the sight glass.

    - Pipe the low-water cutoff (LWCO) drain valve  to a drain, open the valve and let the water run until it's clear.

    - Get a copy of the installation manual; I'd say it wasn't installed per mfg's. instructions.
    Often wrong, never in doubt.
  • SteamheadSteamhead Member Posts: 11,373
    edited March 2010
    That's an older PEG

    possibly an A-series. It looks kind of rough but may still be serviceable. The current PEG series is C, basically the same unit with a different jacket and gas valve placement. Here's a link to the I&O manual which contains a piping diagram:

    You will see that the present piping is nowhere near what it should be. Here are two pics of what it should look like.

    It would be well to have a real steam pro come in and go over the system with you, and verify that the pressure control and low-water cutoff are working, and that the combustion is as it should be (no CO in the flue gas stream, etc). Try the Find a Professional page of this site.

    I have a hunch you have a "Vapor" system, which was the Cadillac of heating back in the day and is still one of the best out there. Have you found any manufacturers' info on any of the original system's hardware? Can you take some pics of a couple radiators too and post them here?
    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.
  • JonnyBJonnyB Posts: 9
    More info

    Before you guys posted, I had spent the day learning all I could about this unit, and then doing what maintenance I knew to do, before firing it up.

    Alan, the water supply line is there, it is just hidden a bit in the picture. However, there is no auto feed. You have to manually open the valve to fill the unit. I am curious to know how often I should expect to fill the unit, assuming there are no leaks anywhere in the system.

    Steamhead, yes, it is an A Series, and yes, it does look rough, but if fired right up, and once it got going, it produced some very nice heat from the radiators. The only thing I noticed was that the water level in the sight glass fluctuated about 1" (1/2" up and 1/2" down from the W.L.). Is this normal? If not, is it bad news?

    You are right, the piping is very different than the piping in your photos. I am wondering, since it seemed to work quite well, do I need to change the piping?

    What is the difference from a steam system and a "vapor" system?

    I'll need to take some pics of the radiators.
  • JStarJStar Member Posts: 2,668
    Water line.

    The water line will always bounce a little. The calmer the better, but you can't expect 212+ degree water to sit still. As long as it doesn't move up and down the whole length of the sight glass, you'll generally be okay. In your case, the pair of bullheaded tees could be causing a little back pressure and rocking the water line a bit. 
    - Joe Starosielec
    [email protected]
  • JonnyBJonnyB Posts: 9

    I really appreciate the posts from you guys.

    If anyone could answer those questions I had in my previous post, that would be wonderful.

    I'll try to get some pics of the radiators today. It is a two-pipe system, however the second return pipe does not start at the opposite end of the radiators, like I have seen in diagrams. There is only one pipe (supply/return) going into each radiator, and then, just before entering the radiator, it T's off to form the return line. Is this common?
  • JStarJStar Member Posts: 2,668
    I've never seen that.

    So, the system is one pipe but the radiator is two pipe. Initially, that sounds like a good way to separate steam and condensate in the radiator. 
    - Joe Starosielec
    [email protected]
  • Welcome to the World of Steam Heating

    Hi- Just a few comments. You may have already done some of these. You might want to check the manual as it will show a measurement for the waterline height. It usually measured from the floor to about the middle of the sight glass. A bounce of 1/2 inch above /below the waterline is normal in operation. Too violent a bounce shows your boiler water is contaminated and you need to skim.

    Manual water feeder.  A lot of people prefer having a manual water feeder as this eliminates the chance of flooding the system.  You should test/blow off your Low Water Cutoff once a week and add water.  New (fresh) water added to the boiler should be brought to the boiler as this drives off excess dissolved oxygen in the water. This dissloved oxygen can be very corrosive to the boiler. Other than replacing the water used in the weekly blowoff/test the amount of water used should be very little.The amount varies between boilers.  I add less than a quart a month (not counting test replacement water) . If you have to add water constantly that means you have a leak somewhere.

    There are some very good books on steam available in the Shop section of this webpage.

    I would recommend for a starter you get "We Got Steam Heat"

    and you also might want to get "The Lost Art of Steam Heating" and Dan's new book "Greening Steam"  These books are written so the homeowner can understand them. They are humorous and packed full of information on residential steam systems. The information and tips they supply very quickly pays for the books many times over.

    - Rod
  • JonnyBJonnyB Posts: 9
    Just the opposite

    JStar, as I indicated on my post just prior to yours, the system is actually just the opposite of what you stated. The radiators have only ONE pipe coming in. Just PRIOR to this incoming line, it T's off to form a return line. So, technically, it is a combination of a two pipe system and a one-pipe system?
  • JonnyBJonnyB Posts: 9
    Thank you

    Rod, yes, I did find a manual to the boiler and set the W.L. per instructions.

    I won't worry about the 1/2" bounce then. Thanks

    I'll probaby just keep it a manual feed then, to avoid the cost of an auto-feed. What happens if the system does get flooded?

    Yes, I have already ordered those books.

    There are a total of 5 radiators. When the boiler was first turned on, it took quite a while to heat up the house to 65, since it had been only about 45 when we first turned it on. Because it was on so long, there was plenty of time for steam to reach all 5 radiators, to produce heat, as they should. However, now that the house is being maintained at about 65 degrees, the boiler only runs for a couple minutes before it shuts off again. Because of this, 1 of the 5 radiators doesn't produce the heat like the other 4, and in fact, doesn't really get hot at all. But if we turn up the stat, to get the boiler to run longer (say about 5 or 10 minutes), then I get heat out of the radiator in question.

    What's going on with the sytem to cause this? Why won't the radiator produce heat during a normal cycle (leaving the stat alone) of the boiler, but yet it does produce heat when the boiler runs for a longer period of time? Is there some kind of adjustment I need to make?
  • One radiator not heating

    It would help if you could post pictures of the system piping, especially the branch that feeds the radiator that doesn't heat well. Please try to get a photo of how the two pipes (steam and condensate return) that connect to the single feed to the radiator so we can understand what the installer was doing.


    If it has just one pipe going to the radiator, the air vent on the side of the radiator may not be releasing air fast enough to let the steam in. You should be able to feel air coming from this vent as long as the system is producing steam UNTIL it gets hot - once it's seeing the steam it will snap shut. Also make sure the radiator is pitched towards the shut off valve so any condensate can find its way back to the boiler. Also Is there another air vent in the area where the steam pipe and the T'd off return pipe connect? If so that vent might be too small or defective.
  • More Info

    Hi-  Glad to hear you have ordered the books. They will be a huge help to you and also make it easier to answer your questions as we can refer you to a page number in the books.

    Automatic Water Feeders- There is a danger that these can malfunction and flood the boiler and possibly your house. They can either get a stuck valve or in some conditions constantly cycle and overfill the boiler. If this isn't caught the piping and radiator cna fill and water can flood out the vents. The Hydrolevel VXT is considered by the pros the best automatic water feeder. It has a lot of safety features and a counter that shows just how much water has been added.

    There are dangers of flooding from manual water feeding also. The valve is turned on to fill the boiler, the phone rings,  the open valve is forgotten and the boil/house floods. One of the ways to eliminate this it to have two valves on the water line. One being a ball valve to shut off the line and then nearer the boiler a spring closing shower valve like they use on public / beach showers. That way the valve can't be left open.  All this is well covered in the books you are getting.

    I'm a bit confused by you one pipe/two pipe system. Perhaps you can give us a picture of the radiator piping so we have a better idea of the system. From your description the only thing I can think of is a Butts Radiator fitting.

    Where is the problem radiator in the system with relation to the boiler and other radiators? It maybe that the radiator vent is malfunctioning. You might want to swap vents

    with another radiator that is working okay. (Be sure to do this with the boiler turned off- Steam Burns aren't fun!) 

    We'll treat your radiators at this point as belonging to a one pipe system. Make sure the valve that lets steam into the radiator is fully open.  On a one pipe steam system, the valve on the pipe going into the radiator has to be fully open or fully closed - preferably fully open. 

    Slope - Use a bubble level and make sure the radiator has a slight slope towards the inlet pipe so the the condensate (water) will drain. This just has to be enough slope to "encourage" the water to drain out. I used quarters ($0.25) piled up as test shims to raise the radiator to determine how much slope I need. Too much slope can be detrimental too.Try the above  and see if they make a difference to the functioning of your "slow" radiator.

    You may want to check and make sure your main vents are working properly. There seems to be some sort of restriction on your vents (see attached) picture that I would consider eliminating.

    Timing - You might want to time your system as this then helps you when you are making changes as you can then determine whether the change is actually beneficial or not.

     If you have several mains time them and the radiators on them separately. If you haven't done so already explore you system and make a drawing as this helps a lot in troubleshooting.

    - Rod

    Typical Timing Sheet

    1. From a cold start how long does it take to make steam? ________ mins

    ( measure this by feeling the risers going from the header to the main.

    - Careful!  These can get HOT!)

    2. How long does it take to get steam to the end of the mains ? ______ mins.

       (Feel the main and/or listen for the main vents to close.)

    3. How long does it take for steam to get to each radiator? ______ mins.

       (Feel the pipe leading into the radiator. Careful! These can get Hot!)

    4. How long does it take for each radiator to fill with steam? _______ mins
  • JonnyBJonnyB Posts: 9
    Thanks a bunch

    Well, I took pictures of everything today, but then I forgot my camera at the house. So for now, here is a very rough sketch of how it is piped.

    From what I have been able to find in what books I do have, it appears to be a modified 2-pipe system rather than a true single-pipe system. Or is this how a single pipe system is done?
  • JonnyBJonnyB Posts: 9
    Another question

    When the stat is turned up enough to cause the boiler to run for, say, 15 minutes or more, all the chambers in all the radiators get plenty hot. However, when the boiler kicks on just to maintain the set temperature, and runs for, say, 2 minutes, only a few of the 8 or so chambers get hot. Is this normal?

    I am assuming that this is only because it doesn't take long enough to satisfy the stat setting, for all the chambers to reach their full output. In other words, the temerature in the room reaches the set temperature before the boiler system really gets going in full speed. yes, no?
  • JonnyBJonnyB Posts: 9
    And another

    I forgot to mention. I increased the setting on the pressure control, just a little, and it seemed to improve the problem radiator. What should I have this control set at? and could this have an effect on getting steam to a particular radiator that may be further down the line?

    The control was set between 1 to 2 pounds. I changed it to 3.
  • edited March 2010
    Radiator not heating fully

    This usually indicates the radiator is not venting the air in it fast enough, or there is an issue with the pitch of the pipe that feeds steam to the radiator. The radiator could also have a blockage in oit that is im peding the flow of steam / condensate).

    Your sketch shows the piping but does not show any venting on the piping. If there are vents on the pipes before the radiator, are they working - can you feel or hear air coming out?

    If the only venting is on the radiator, is it working? Buy a radiator air vent at a hardware store and try replacing the one on the slow radiator with an adjustable vent. That valve is about half way up the radiator opposite the valve that feeds steam to the radiator.

    Make sure the pipe that feeds the steam to the radiator is pitched back towards the boiler , it is usually a very small pitch (1in in 20ft I think) The pipe that feeds the condensate back to the boiler should also be pitched back to the bopiler. 

    Post the pics of what your piping is like and a pic of a radiator that shows the steam input and the venting on the radiator.

  • JonnyBJonnyB Posts: 9
    Will do

    And thank you for the input.

    The only vents in the piping are the ones you see in my previous photo.

    All of the radiator air vents appear to be working. They have a screw that, once loosened, allows you to rotate a cup-shaped ring that has numbers from 1 to 10. I adjusted the problem radiator to 10 and it seemed to help. I'll know more when I go back to the house in the morning.

    This is my very first experience with steam heat. I think it is pretty cool. And the heat is of great quality.

    I'll try to get those photos on here tomorrow.
  • edited March 2010
    One Pipe Parallel Flow

    Your diagram is a parallel flow one pipe system. The steam and condensate (water) flow the same direction down the steam main and back through the return main. The is only one pipe connected to each radiator.   On a two pipe system, there is also a steam main and a return main but each radiator has one pipe connecting it to the steam main and another pipe on the opposite end of the radiator connected to the return main. There is also another type of one pipe steam system called a one pipe counter flow system. This has only the steam main, it is sloped towards the boiler . The steam travels up the main and condensate returns back down the steam main to the boiler, hence the word "counter flow". I've attached a diagram of a typical one pipe parallel flow system.
  • Radiators

    Yes it's okay that the whole radiator isn't hot. This happens more often early in the fall and late in the spring when it is warmer as the temperature of the thermostat is satisfied before the radiator fully heats. 

    You don't want to raise the pressure on the boiler!  The maximum you should ever have on a residential steam system is 2 PSI!  Lower pressure = Better!  Steam travels faster a low pressure. Here's a link where Dan explains why.

      A lot of systems operate at under 1 PSI!  You just need to do some adjusting on the venting, possibly on both the main vents and the radiators. If there is air in the radiators, steam can't get into the radiators. Why raising the pressure seems to help this is that the higher pressure compresses the air and allows the steam to move farther into the radiator. This is a "false cure".  Building pressure wastes fuel! What needs to be done is get the air out through better venting so the steam can fill the radiator completely. 


     While you're waiting for Dan's books, Here's a link to a website with a lot of good information on steam heating. Gerry Gill is one of the top steam pros on this board.

  • JonnyBJonnyB Posts: 9
    Great info

    I really appreciate all the feedback from you guys. Very helpful.

    So, would it make sense to just turn that pressure control down to the lowest setting then?

    Also, is there a place online that you guys would recommend for buying air vents?
  • Vents

    How low a pressure you can operate your system depends on the system itself . You have some issues with your near boiler piping which may limit you.  Lowering the pressure is a trial and error thing. You try different adjustments and lower the pressure down to the lowest point the system will still satisfactorily work.  At this point I'd return it to it's original settings and leave it there until you know more about steam. One rule I always follow is make only one adjustment at a time. If you make several changes at one time you never know which one is beneficial or detrimental. \

    Vents- Where are you located? There should be a local supplier where you can get vents. A lot of people on this website use Pex Supply on the internet. What sort of vents do you have now? See if you can find some names and numbers on the vents.

    - Rod
  • JStarJStar Member Posts: 2,668
    edited March 2010

    Very, very highly recommend that you also purchase the Vent Capacity Chart from this website. It will let you know exactly what the air in your system is doing, and how to make the right changes.
    - Joe Starosielec
    [email protected]
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