Method for operating a dishwasher fluid circulation assembly

A method for operating a dishwasher fluid circulation assembly, the fluid circulation assembly including a main pump and a drain pump in flow communication with one another through a sump, a fine filter assembly in flow communication with the main pump and including a filter body and a fine filter screen disposed over the filter body, the filter body including a fluid inlet and a drain tube in flow communication with the drain pump, and a check valve in flow communication between the main pump and the drain pump, the fluid circulation assembly including a lower spray arm assembly, a spray arm conduit, and a hub assembly establishing flow communication with the spray arm conduit and the lower spray arm assembly, the lower spray arm assembly having a lower spray arm, said method comprising the steps of:

• activating the main pump to pump wash fluid in the fine filter assembly, said step of activating the main pump further comprising the step of feeding the lower spray arm and the spray arm conduit through the hub assembly, the spray arm conduit supplying water to at least a spray arm other than the lower spray arm;
• activating the drain pump while the main pump is activated to drain the fine filter assembly and to concurrently drain the sump;
• operating both the main pump and the drain pump for a selected time period, thereby flushing the fine filter assembly,
• de-activating the main pump;
• and
• operating the drain pump to drain the fluid circulation assembly.