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Replacement flow control valve?

nz Member Posts: 125
Still learning about hot water heat, only been in this house for 10 months. I fixed a lot of bleeder valves over the winter but there was one baseboard that wouldn't heat up. I bled all the air, and the supply pipe was warm but the radiator never heated up unless I bled a lot of water out too (just as an experiment.)

I think this valve is frozen shut, and despite all my attempts to open it, they have failed.  I think this is a flow control valve, it had a knob on it at one point I'm sure like the rest of the house. 

I'm thinking about replacing it with this danfoss double solder TRV. I installed 15 TRVs at my old house that had steam successfully, but given my inexperience with hot water I thought I would check with the forum first.  Is this Danfoss valve (plus the operator) a suitable replacement? 





  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,618
    That valve Danfoss valve looks fine.

    Here is a booklet that may help you understand Hot Water systems
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • hot_rod
    hot_rod Member Posts: 21,898
    I don’t recognize that as a TRV, probably a manual valve of some sorts. Although it looks more engineered than a globe or balance valve?

    If you put a TRV there, any baseboard in series with that one will be regulated also, by the temperature at that location.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • The stem probably stuck out of the baseboard cover with some kind of handle on it. TRV? I have no idea what that capped port is for. Adjustment?
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • mattmia2
    mattmia2 Member Posts: 9,475
    You might open it up and see what's inside. It should unscrew.