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John_178 Member Posts: 2
I called one of the guys at a website on this forum and he said I can use single pipe injection valves for my one pipe cast iron rads. He said I can use( ONE) 1/2" Pex which would function as both the supply and return and run it to my old radiators(One pipe steam). He said I could snake it through the old pipes. He also said I can use any boiler and use a non electric thrmostatic valve one each rad to basically control the temp individually on each one. Anyone ever hear of this?


  • ALH_4
    ALH_4 Member Posts: 1,790

    That sounds absolutely insane to me. I would upgrade and repair the steam system long before attempting anything like that.

    I guess theoretically you could supply through the pex line and return inside the old steam line, but installation would be a complete nightmare and I certainly would not guarantee it would work. I don't think it's possible to get 1/2" pex snaked through the old steam pipes, even if you ignore all the other problems with steam conversions.

    Please, stick with your steam system.
  • John_178
    John_178 Member Posts: 2

    Andrew forget about the steam pipe for the return. He was just saying to snake to use the exisiting holes. He said even without the steam pipe that the 1/2" pex would act as both the supply and return. Is this possible?
  • Rich Kontny_5
    Rich Kontny_5 Member Posts: 116

    Refering to some of the European systems Dan mentioned at his Hydronics Seminar. I would have to look up my notes but I know it does not work as a retofit.

    Otherwise I would have looked for the hidden camera as this guy was handing you a line of B.S.

    Rich K.
  • ALH_4
    ALH_4 Member Posts: 1,790
    Diverter tees?

    Ohhhh, he must have been talking about a diverter (monoflo) tee system?

    If that is the case, then this is very possible. You could run into problems with the radiators leaking after the conversion because they have never held water before.

    Thermostatic radiator valves are an excellent way to control your radiators. Be careful of the reduced heating output of your radiators when using hot water.
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