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Old hot water heating system with cast iron radiators

djfreni
djfreni Member Posts: 13
I have a customer that has a 20 year old Wiel McClain boiler. It has a small Taco 007 circular on it with two heating zones with zone valves. She has a problem with one huge radiator on the 1st floor dining room not heating up much at all, but the exact same radiator in the living room right next door is blazing hot. Should I put in a bigger circulator like a B&G 100 series?

Comments

  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Have you tried bleeding the cold radiator?—NBC
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Please dont just put on a bigger circ, and if you do at least get a wet rotor, not a 3 piece.

    Find out if it heated before, and if so, what has changed? If it's never worked, then look into why.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
    IronmanSuperTech
  • bob eck
    bob eck Member Posts: 930
    Vent the radiator. Is the radiator valve open? The old radiator valve could be broken and you might think it is open and it might not be open.
  • flat_twin
    flat_twin Member Posts: 350
    New problem with that radiator or long time issue?
  • djfreni
    djfreni Member Posts: 13
    Long time issue. Valve are wide open and no air in any radiators
  • JohnNY
    JohnNY Member Posts: 3,226
    Use a laser thermometer to measure the temperature drop from supply to return on each radiator. Using the shut off valves, try to even them out to steal flow from the over-pumped radiators to the underperforming unit. Balancing is an often overlooked part of the hydronic heating process.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
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    djfreniIronmanGordy
  • djfreni
    djfreni Member Posts: 13
    Piping is all oversized. Probably gravity system way back
  • djfreni
    djfreni Member Posts: 13
    Thankyou JohnNY
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    I would also valve out closer radiators to see if you can get heat to the cold unit.

    Is it a direct return? Or reverse return?
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
    djfreni
  • Gordy
    Gordy Member Posts: 9,546
    If this is a converted gravity system it could be possible there were originally restrictor baffles in the radiator in question that were never removed in the conversion.

    I find it all most hard to believe that this was a problem from the initial conversion though. But weirder things have happened on new installs left as fully functioning work.