I have my piano in a room which is approx 4' x 8'. It's very cold in this room, so I have a portable heater in there, which I keep on permanently on the lowest setting, so that the temperature doesn't fluctuate. I also bought a humidifier so that the room doesn't dry out, which would also cause the piano to go out of tune. The problem is I can't keep the humidifier on all the time because it pumps an insane amount of moisture into the air, making everything a bit damp lol. Also I think it may be having an effect on the piano, because after a few days of having it on the piano seems "duller", quieter even.
My question is, when should I put the humidifier on, and how long for, to ensure that the room is not drying out, but its not getting to humid either?