Yeah, same here. When it's -10 C or less in the winter, relative humidity can drop to 15%. Because we have a standard heat-exchanger HRV. The rotating-filter o

Yeah, same here. When it's -10 C or less in the winter, relative humidity can drop to 15%. Because we have a standard heat-exchanger HRV. The rotating-filter ones do manage humidity, but they also tend to freeze up if indoor humidity goes too high. So we end up using an aerosol humidifier in the winter, and AC plus a dehumidifier in the summer.