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Converting Oil/Steam heat to Gas/Hot water heat

FrankZ11B Member Posts: 2
<span style="font-size:16pt">Hello,

I am currently renovating my house. Its a 1925 wood frame currently with a monster of a oil furnace. Its a one pipe steam system that each cast iron radiator in the house is connected to a 3" pipe in the basement. I will be converting from oil/steam to gas/hot water in the near future. I plan on doing the following things and any advice would be greatly appreciated:

<strong><span style="text-decoration:underline;">1)</span></strong> Convert entire heating system in the house from steam to hot water.

<strong><span style="text-decoration:underline;">2)</span></strong> Reuse all cast-iron radiatiors in the house (all of which are in excellent condition).

<strong><span style="text-decoration:underline;">3)</span></strong> Remove old 1-pipe system.

<strong><span style="text-decoration:underline;">4)</span></strong> Install radiant heat manifolds for supply/returns , a 4-loop mainfold for the 1st and 2nd floor, thus creating two different heating zones.

<strong><span style="text-decoration:underline;">5)</span></strong> Using 3/4" Pex-Al-Pex, run supply/return lines to each radiator. Due to some of the runs being a bit of a distance, ie: the boiler is located in the rear of basement and the furthest radiator is the upstaris front of house, is it okay to use elbow/straight union fittings to keep the supply/return runs headed to the heat manifolds from getting kinks (pex-al-pex can be bent only so much), etc?

<strong><span style="text-decoration:underline;">6)</span></strong> I would like to do a reverse return loop for the zones but it would be extremely difficult to do due to the structure/layout of house. I am leaning towards just running dedicated supply/return lines to each radiator supply coming in bottom left and return coming out of bottom right with a air vent on the top right. Reason for choosing this method is the ease of access to each radiator. What are your thoughts on this?

Any thoughts/information/advice would be greatly appreciated.

Thanks in advance,

Frank Z

" Never forget our fallen, for once a brother always a brother"



  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    You can save a lot by staying with Steam

    at least 30% with a properly sized and installed steam boiler. Maybe even 50% better fuel savings. Not all steam radiators can be used for hot water. Converting can cause leaks where there were no leaks.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • FrankZ11B
    FrankZ11B Member Posts: 2
    edited May 2011
    Thanks for the response


    Thanks for the response. I do agree with you on keeping the steam. The system that's in place now is in need of a lot of work, almost not worth going through all the trouble and headaches. As for switching to oil/ steam to gas/ hot water I have a few things. One being if I make the switch my gas supplier will provide me with a free he gas boiler which would be a huge cost savings considering most of the units they supply are in the $2000 range. As for supplies I had a friend who had left over material from another job being 500' of rifeng 3/4" pex-al-pex along with all the fittings I would need including 2 4-loop supply/return heat manifolds that he just gave to me when I mentioned upgrading my heating system, what a good friend. With a deal like that I can't go wrong. As for my castiron radiators they are all going to be restored and tested for leaks. As I mentioned before I wanted to do reverse return loops for each zone being the first and second floor but due to structure and layout not very easy. Easiest way is to run individual homerun supply/return lines from the heating manifolds in basement to each individual radiator. Doing that would be aolt easier. As for the rest of the house all brand new energy star rated triple pane pella windows throughout including all new entrydoors. The entire house has been insulated with 3 inchs of sprayfoam insulation. Just having to figure out my heating situation and where I am gonna go with it.

    Any advice anyone?
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    Home runs are fine but work best

    if you use TRV's on the radiators. Are the radiators connected along the top? Before you start ripping things out I want to make sure they can be converted to hot water. Hydronic Alternatives makes a radiator valve for conversion to hot water that does not require the removal of the plug on the opposite end of the radiator. This can sometimes mean the difference between a broken radiator and a good one. A variable speed pump would be best and the use of outdoor reset is also a no brainer as with all the new insulation the radiators should be able to run lower temps. Have you done a heat loss yet for the structure? Have you done a surevey of the edr of the radiators to make sure they will produce enough heat at the lower temperatures of a hot water system?
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • Steamhead
    Steamhead Member Posts: 16,732
    What boiler

    is the gas company offering? 

    Will your radiators work with hot-water? Charlie's right, many won't. Post some pics if you're not sure.

    Have you done a heat-loss calculation? How do the radiator sizes compare- will they put out enough heat with hot-water?

    It's not just a simple matter of running PEX. You have a lot of things to consider. We find that fixing the steam is usually the best solution. Why do you say your system is not worth fixing?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
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