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Need help with and old coal furnace converted to a natural gas radiant heat

I have an old coal burning furnace (1942), that has been converted to a natural gas radiant heat furnace (burner).  It is in my basement and I have several rooms upstairs that have little to no heat coming out of the registers.  (I don't know if they are technically called 'registers', I have the pipes running along the ceiling in the basement that carry the hot steam/water throughout the house and the extensions run off the main pipe up into the up stairs rooms.  They (the registers) are not free standing, they are long flat heating distributors that are an extension from the heating pipes coming from the basement.)   Anyway, there are several of these that there is little to no heat coming out of them.  Does the PSI's on the furnace have anything to do with this?  Somebody also told me to loosen or tighten the screws that are in the smaller tubes at the beginning of the heating unit. 

I don't know if anyone will be able to understand exactly what I am needing help with, but, I am certainly open to any help I can get at this point.


  • JStarJStar Posts: 2,668

    You've been using terminology that describes several and very different types of heating systems. So, first, let's discover what type of heat you do have.

    At the boiler, do you see a vertical glass tube, about 1/2" thick by 12" tall? Does the boiler have a pump?
    - Joe Starosielec
    [email protected]
  • Jamie HallJamie Hall Posts: 6,433
    I might add to Joe's comment

    that a few pictures just might help, if you can manage it.

    Although it sounds, on the face of it, that it might be a gravity hot water system -- in which case, the psi would make a difference.  It would with steam, though, too, in a different way.

    So... to be really helpful, and we would like to be, some pictures, please!

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-McClain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • pics have been posted

    pictures have been posted.  thanks.
  • pics have been posted

    Pictures have been posted.  Thanks.
  • JStarJStar Posts: 2,668
    edited September 2013

    Congratulations. You have steam!

    The heat emitters are called convectors. The air vents are probably stuck closed. It would be a good idea to upgrade them if it's never been done. It may also help to vacuum the convector fins. They require airflow for proper heat production.

    Where are you located? We may know somebody nearby that can offer a helpful site visit.
    - Joe Starosielec
    [email protected]
  • nicholas bonham-carternicholas bonham-carter Posts: 6,480
    edited September 2013
    Old steamer

    It appears you have a steam boiler, which supplies several one-pipe baseboard radiators.

    A number of things may be wrong with the system, from the thermostat to the radiator vents, and you need a good steam man to help you make this system work as it did when first installed. This is a matter of someone with the knowledge of which stew to turn!

    I'll list a few things which may have happened:

    1. The anticipator of the thermostat may have fallen out of adjustment, causing the boiler to shut off early.

    2. The venting in the cold radiators may be plugged, causing difficulty in air removal during steaming.

    3. The waterline may be unstable, causing the boiler to stop in mid-cycle, before those radiators get steam.--NBC
  • STEAM furnace

    I am in Northern Utah.
  • STEAM furnace

    I might as well say this now, I am a single parent (Mom), trying (and learning!) to do this on my own.  So, if you have any info that can help me -- please, please explain it so that I can understand it. . .  Thanks so much!
  • nicholas bonham-carternicholas bonham-carter Posts: 6,480
    edited September 2013
    Making you another steam lady

    We'll do what we can to help you run some tests.

    1. Make sure you can turn off the boiler at the switch. Which cuts power to the boiler. If there is no switch, tell us, before proceeding.

    2. Turn the thermostat down to 40 degrees

    3. Only with the boiler off both ways, (to avoid steam burns), unscrew the baseboard vent on the end away from the valve, which you can see in your 3rd picture. It should be hand turntable. This should be on the cold radiator.

    4. When it is off, wash it in the sink with some soapy water, shake the water around inside it with your finger over the big threaded end at the bottom,and rinse.

    5. Hold it vertically (important), and try to blow through it.

    6. Screw it back into the radiator when you are finished, with a tiny bit of soapy water still on the threads. You will be able to feel by the smooth turning that it is seated in the threads. If it is immediately tight or rough, reverse your direction, and try again, until hand tight.

    Tell us what you found after the test of one radiator. When you turn on the boiler, watch that vent closely as it fires to make sure there is no leak.--NBC

    P S-When you reply to the questions, do so in the steam section here, where more steam experts are checking for interesting problems to solve. Repost the pictures there as well.

    Is this your house, or a rental?
  • BobCBobC Posts: 4,335
    These should help

    This is a nice short primer on steam systems -

    This is an article on steam systems do's and dont's -

    There are books available on this site that will give you more information but the above articles are a good start to understanding what you have. If you have any questions just ask and someone will try and explain how something works or how something can be done.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Jamie HallJamie Hall Posts: 6,433
    Northeast Utah?

    Oh boy.  Not sure we have any experts in those parts -- but anyone who is a single mother and has the ability to live there should be able to figure out -- with some help from all of us -- what to do next, and how to do it.

    Don't be afraid to ask questions.  There is not such thing as a stupid question. We will try to avoid stupid answers, though.

    The whole process may take a while, though -- patience.

    Do get Dan's books -- there is a nice set of them available from the "shop" tab here, and they are well worth the money.

    When you need new bits -- and it is likely that you will -- we may be able to recommend which ones, and, perhaps more important, where to get them.  There is no future in taking the time to install poor quality fittings and, unfortunately, that is all that tends to be available in the big box stores.

    NBC has given you a nice start with seeing if you can clean up one vent and seeing how that goes.  What he didn't mention is that when you hold it vertically -- as he suggested --- and try to blow through it, you should be able to.  I might also add that if the soap and water and shake treatment doesn't free it up, you might try repeating it, only with vinegar and letting it soak for a bit, then rinsing it again and trying again.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-McClain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • Baseboard rad vent

    Jaimie, have a look at the picture, because I think it is a vertical vent, and not right angled. Therefore the vent should open in the vertical, and close upside down. Wait until we get into describing the cleaning of the pigtail!--NBC
  • Jamie HallJamie Hall Posts: 6,433
    right you are, there...

    looked too fast, or too little, or something.

    Bet she'll get that system singing along as it should, though!

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-McClain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • SWEISWEI Posts: 7,356
    700-D Pressure Control

    I really love the industrial design on that old pressuretrol.  Google doesn't seem to find much on it, though.
  • JUGHNEJUGHNE Posts: 2,857
    More pictures...

    would be good.  Something showing the pressure gauge (the PSI you mentioned); anything that looks like a "pigtail" loop of tubing with maybe the gauge on it;  something called a pressure relief valve--on top/side of boiler--brass with a steel handle on it.  And have you ever operated the yellow lever for "blow down"??  I wouldn't do it yet until you are familiar with the operation of it and it should have a short pipe attached if possible.  I sent you an E-mail (still 2 states and one time zone away)...Good luck!!
  • It is officially steam. . . .

    To everyone who has been so helpful -- Thank You!!  I, unfortunately have had to put the furnace off for a minute.  My hot water heater has started leaking and is creating a huge mess for me in my family room downstairs.  UGH!  I am hoping to get this current issue taken care of in the next week, and then it will be back to trying to figure out my 70+ year old 'steam' furnace.  I will definitely be open to all suggestions to getting my furnace to work better!  :)
  • It is officially steam. . . . .

    First off, thank you for your suggestions regarding my old coal converted furnace.  I am so glad there are people out there willing to help.  I have been having problems with my hot water heater, so, the furnace has been put on hold for a minute.  I never did receive your first e-mail, but obviously, I received the second.  I will try to post more pics after I get my hot water heater replaced.  I do operate the yellow lever, every couple of weeks, (especially in the winter months).  I think that it is to get the sludge (?) out of the boiler??  I just know that I have to operate the lever, and allow the yucky water to drain into a bucket until the water is clear.  I am sorry that I do not know the technical terms for all this.  But, I appreciate the help.
This discussion has been closed.


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