Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Disappointing performance

I've had the unit in operation for about 3 weeks, with minimal impact on the humidity level in my house. Based on the size of the house, this unit should be more than adequate. However, using the humidistat as an indicator, the humidity level (the point at which the humidistat energizes the humidifier) is unchanged. The unit is operational, the filter is installed as instructed, and water flows from the drain, so I'm not sure why the poor performance.