Laundry treatment appliance including a variable speed blower fan and method of operating the same

A laundry treatment appliance, comprising:

• a cabinet;
• a drum rotatably mounted within the cabinet, the drum defining a chamber for receipt of articles, the drum defining a drum outlet and a drum inlet to the chamber;
• a sealed system configured to heat and remove moisture from process air flowing therethrough, the sealed system comprising a compressor operable to urge a refrigerant through a refrigerant line;
• a duct system for providing fluid communication between the drum outlet and the sealed system and between the sealed system and the drum inlet, the duct system, the sealed system, and the drum defining a process air flow path;
• a blower fan operable to move process air along the process air flow path, the blower fan capable of operating at variable rotational speeds;
• a temperature sensor provided within the duct system at the drum outlet to sense a temperature of the process air at the drum outlet;
• a humidity sensor provided within the duct system at the drum outlet to sense a relative humidity of the process air at the drum outlet;
• and
• a controller configured to perform an operation, the operation comprising:
• directing the blower fan at a preliminary rotational speed;
• determining a condensation capacity of the sealed system with regards to the process air in the duct system;
• estimating an air flowrate of the process air at the drum outlet;
• determining a mass flow rate of moisture in the process air while directing the blower fan at the preliminary rotational speed, wherein the determined mass flow rate of the moisture in the process air is based on the estimated air flowrate, a sensed relative humidity, and a sensed temperature of the process air at the drum outlet;
• determining a target rotational speed of the blower fan corresponding to a set ratio of the determined condensation capacity to the determined mass flow rate;
• and
• directing the blower fan at the determined target rotational speed.