Fault detection for a water level detection system of a washing machine appliance
AssigneeHaier US Appliance Solutions, Inc.
InventorCharles Derek Hibdon
Life of this patent
Estimating the term…
Abstract
A washing machine appliance includes a sump for collecting wash fluid, a drain pump for discharging the wash fluid from the sump, and a water level detection system fluidly coupled to the sump. A controller is configured for monitoring the electric current drawn by the drain pump during a drain cycle and determining that the sump is empty based on a drop in the electric current. The controller then measures the sump pressure and determines that a fault condition exists with the water level detection system when the sump is empty and the sump pressure exceeds a predetermined pressure threshold, e.g., zero pressure corresponding to an empty sump.
Claims20
A washing machine appliance comprising:
- a sump for collecting wash fluid;
- a supply valve for providing the wash fluid into the sump;
- a drain pump for discharging the wash fluid from the sump;
- a water level detection system comprising a pressure sensor fluidly coupled to the sump;
- and
- a controller operably coupled to the supply valve, the drain pump, and the water level detection system, the controller being configured to:
- measure a sump pressure using the water level detection system;
- operate the drain pump to drain the wash fluid from the sump during a drain cycle;
- measure an electric current drawn by the drain pump during the drain cycle;
- determine that the sump is empty based on the electric current drawn by the drain pump;
- and
- determine that a fault condition exists with the water level detection system when the sump is empty and the sump pressure exceeds a predetermined pressure threshold.
A method for operating a washing machine appliance, the washing machine appliance comprising a sump for collecting wash fluid, a drain pump for discharging the wash fluid from the sump, and a water level detection system fluidly coupled to the sump, the method comprising:
- measuring a sump pressure using the water level detection system;
- operating the drain pump to drain the wash fluid from the sump during a drain cycle;
- measuring an electric current drawn by the drain pump during the drain cycle;
- determining that the sump is empty based on the electric current drawn by the drain pump;
- and
- determining that a fault condition exists with the water level detection system when the sump is empty and the sump pressure exceeds a predetermined pressure threshold.
Dependencies are inferred from the claim text.