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Introduce me and my 2 steam boilers

DsissonDsisson Posts: 53Member
I just purchased a duplex w 2 steam systems. 1930 vintage home. Upper unit has a new gas boiler. Lower has the original coal boiler converted to gas.

I'm working to get a good contractor over to take a look at the system and see if the system was installed correctly and needs any work.


1: should old boiler be replaced due to age and or inefficiency?

2: can the systems be extended to add radiators to an addition to the house? If yes, how to size a new boiler?

Any recommendations in the Providence RI area for contractors?


  • nicholas bonham-carternicholas bonham-carter Posts: 7,778Member
    Picture worth a thousand words

    Take some pictures of the boilers/radiators, and label each as old boiler-new boiler if possible. One pipe or two?

    Get a copy of " the lost art of steam heating here, and it goes into the procedure of measuring the radiators to size the boiler.

    Get 2 low-pressure gauges (0-3 psi, gauge and put them on the same pigtails as the pr essuretrol, leaving the 0-30 psi for code requirements.

    Can you find any history on the boilers performance? If there is any suspicion of leaking, then this would be a good time to do an over filling leak test, as there is time to let them sit. Check the find a contractor dept here for recommendations listed by state, if none listed, don't worry, you will become your own expert with our help!.--NBC
  • BobCBobC Posts: 4,929Member
    pictures and a list

    I agree with Nicholas and i would suggest two posts, one for the old boiler and it's piping and a second for the new boiler and piping.

    Extending a steam system has to be done by a good steam man. if it's not done just right it won't work. If the building extension is not to large you could pull a forced hot water loop off the steam boiler. In either case you need to find someone that really understands steam, good steam men have to be sought out because they are not easy to find.

    Steam boiler are rated in BTU's and sq ft of steam, the sq footage of radiation (Surface area of a radiator is it's EDR) should be equal to or somewhat less than the boilers rating. If the sq footage of radiation is more than the boilers rating you will never get everything hot, if the rating of the boiler is grossly more that the sq footage of radiation you will be inefficient.

    On both systems make a list of radiators and their EDR (list the height, width, depth, number of colums per section, and the nember of sections (assuming these are radiators and not basboard or finned units). There are tables that will let you easily find the EDR of almost any radiator - "The Lost Art of Steam Heat" has a pretty good table in it (pg 71,72). Then find the ratings plate on the boiler that lists the name and model of the boiler, the sq ft of steam, and BTU's and add that to each of your lists.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • DsissonDsisson Posts: 53Member
    thanks guys

    I'll start making an inventory of the radiators and the boilers, look over the calcs and post back with photos. I will also get some books to help me along.
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