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reverse thermostatic valves?

jumper Member Posts: 2,289
The opposite of what car engine cooling systems had.
These open only when return water gets cool enough.
In this way delta T is maintained for each circuit.
Were such devices used in the fifties?


  • Bill_17
    Bill_17 Member Posts: 68
    These are typically called return temperature limiters, they are definitely available for single loop radiant circuits (small loads) and in larger sizes they have other names, most then have remote sensors attached to the valve actuator via a capillary tube.
  • hot_rod
    hot_rod Member Posts: 22,261
    Probably not available in the 50's. The Caleffi ThermoSetter, a thermal balancing valve, opens as temperature drops, to maintain a setpoint temperature.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream