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Resistor in a Room Thermostat

  • 25-03-2022 11:28pm
    Registered Users Posts: 11,795 ✭✭✭✭

    Years ago I remember taking apart an old (230vac wired) room stat and finding there was a resistor (think it was across the contact terminals) - well today I took apart a modern roomstat (230v AC wired) and there is no resistor in it (well apart from one for the neon light which is normal).

    was the resistor there in the old one to stop pitting of the contact(s) or was it there to make the room-stat more precise (or both?)

    If i wanted to fit one in this modern one , what value resistor would I use?

    The modern stat seems to not turn on and off without ... how can I describe it , er fizzing noise I suppose you could call it only for a split second - I have a TV and radio in the room and there is no like interference on the TV as it turns on and off , its just like not turning on and off nice and cleanly. They dont cost a lot I know so I can always go out and buy another from a plumb shop or homebase /woodies etc but I was maybe just going to try adding a resistor in it .