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CI radiators

jjtwd Member Posts: 2
I'm hoping that someone can explain exactly how may CI radiators work. I'm running an outdoor boiler system with a heat exchanger in my furnace and some CI radiators to heat my shop. I'm just getting things ready to start using the system. The other night I removed the two larger nuts from one of my radiators in order to had some PEX hardware. My rad is one that has two pipes on the bottom both on the same side. Basically they are next to eachother. I reached inside the rad to check for dirt and realized that I could fell the other hole. So my question is how does the rad fill full of water if the inlet and outlet are connected right inside the rad. I equate this to a bucket that has two holes at the same level ( around the bottom). If I add water through one of the holes the bucket will never fill up as the water will just run out the other hole? Is there something wrong with this rad ( it's not rusty on the outside). Can someone please explain if this is normal and how exactly this rad is going to fill full of water ( or does it). It's not a steam rad. Thanks


  • Ironman
    Ironman Member Posts: 7,379
    Is this what you have?

    Water movement inside the columns of the rad is achieved by gravity: the hotter water has less boyancy and rises while the cooler water is heavier and goes back down.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • jjtwd
    jjtwd Member Posts: 2
    Ironman, thanks. Should I be able to touch my fingers together when reaching through the two pipes holes? Yes same type of rad.