Washing appliance with improved circulation pump control

A washing appliance comprising:

• a tub configured to house items to be washed;
• an inlet valve operable to be selectively switched between an open condition for causing washing fluid to be loaded into the tub and a closed condition for preventing washing fluid be fed to the appliance;
• a circulation pump configured to circulate the washing fluid in the tub during a washing cycle;
• a control unit configured to determine an operative state of the circulation pump between (i) a saturation state indicative that sufficient washing fluid is present in the tub to prevent air from being drawn out by the circulation pump, and (ii) a starvation state indicative that insufficient washing fluid is present in the tub to prevent air from being drawn out by the circulation pump, wherein the control unit is further configured to receive an indication of a target speed for the circulation pump and control the circulation pump by:
• causing a speed of the circulation pump to increase towards the target speed with a first speed increase rate if both conditions a) and b) are met:
• a) a starvation state of the circulation pump is determined before the speed of the circulation pump reached the target speed, and
• b) the inlet valve is in the open condition;
• and
• causing the speed of the circulation pump to increase towards the target speed with a second speed increase rate lower than the first speed increase rate.

A dishwasher comprising:

• a tub;
• an inlet valve operable to be selectively switched between an open condition for causing washing fluid to be loaded into the tub and a closed condition for preventing washing fluid be fed to the appliance;
• a circulation pump configured to circulate the washing fluid in the tub during a washing cycle;
• a control unit configured to determine an operative state of the circulation pump between (i) a saturation state indicative that sufficient washing fluid is present in the tub to prevent air from being drawn out by the circulation pump, and (ii) a starvation state indicative that insufficient washing fluid is present in the tub to prevent air from being drawn out by the circulation pump, wherein the control unit is further configured to receive an indication of a target speed for the circulation pump and control the circulation pump by:
• causing a speed of the circulation pump to increase towards the target speed with a first speed increase rate if both conditions a) and b) are met:
• a) a starvation state of the circulation pump is determined before the speed of the circulation pump reached the target speed, and
• b) the inlet valve is in the open condition;
• and
• causing the speed of the circulation pump to increase towards the target speed with a second speed increase rate lower than the first speed increase rate.