Water heater appliance

Abstract

A heat pump water heater and a method for controlling a relative humidity in an environment including the heat pump water heater are provided. The heat pump water heater includes an evaporator, a condensate collection tray, and a condensate pump for discharging collected condensate. Notably, the amount of condensate collected correlates to the humidity level in the environment. Therefore, an exemplary method contemplates determining an average operating value of the condensate pump, the average operating value being a function of the pump operating time and the condensate pump rate. Based on the temperature of the environment and the average operating value, the relative humidity may be determined and the operation of the heat pump water heater may be adjusted to regulate the relative humidity.

What is claimed is: 
     
         1 . A method for controlling a relative humidity in an environment including a heat pump water heater, the heat pump water heater comprising a compressor, a condenser, and an evaporator, the method comprising:
 determining an average operating value of a condensate pump of the heat pump water heater, the condensate pump being in fluid communication with a condensate collection tray for discharging condensate collected from the evaporator of the heat pump water heater;   determining a temperature of the environment;   determining, based on the average operating value and the temperature of the environment, the relative humidity of the environment; and   adjusting an operating parameter of the heat pump water heater to regulate the relative humidity of the environment.   
     
     
         2 . The method of  claim 1 , wherein determining the average operating value comprises determining an operating time and a condensate pump rate of the condensate pump during a predetermined time interval. 
     
     
         3 . The method of  claim 2 , wherein the average operating value is the operating time multiplied by the condensate pump rate over the predetermined time interval. 
     
     
         4 . The method of  claim 2 , wherein the predetermined time interval is eight hours. 
     
     
         5 . The method of  claim 1 , wherein the operating parameter is a speed of the compressor of the heat pump water heater. 
     
     
         6 . The method of  claim 1 , wherein the operating parameter is a cycle time of the heat pump water heater. 
     
     
         7 . The method of  claim 1 , wherein the temperature of the environment is measured at an inlet of the evaporator. 
     
     
         8 . The method of  claim 1 , wherein the temperature of the environment is measured outside of the heat pump water heater. 
     
     
         9 . The method of  claim 1 , wherein the temperature of the environment is measured both at an inlet of the evaporator and outside of the heat pump water heater. 
     
     
         10 . A water heater appliance defining a vertical direction, the water heater appliance comprising:
 an evaporator being configured to absorb heat and produce condensate;   a condensate collection tray disposed under the evaporator along the vertical direction and being configured for collecting the condensate from the evaporator;   a condensate pump in fluid communication with the condensate collection tray, the condensate pump being configured for discharging the condensate from the condensate collection tray through a condensate discharge line; and   a controller for controlling a relative humidity in an environment in which the water heater appliance is located, the controller being configured for:
 determining an average operating value of the condensate pump; 
 determining a temperature of the environment; 
 determining, based on the average operating value and the temperature of the environment, the relative humidity of the environment; and 
 adjusting an operating parameter of the heat pump water heater to regulate the relative humidity of the environment. 
   
     
     
         11 . The water heater appliance of  claim 10 , wherein determining the average operating value comprises determining an operating time and a condensate pump rate of the condensate pump during a predetermined time interval. 
     
     
         12 . The water heater appliance of  claim 11 , wherein the average operating value is the operating time multiplied by the condensate pump rate over the predetermined time interval. 
     
     
         13 . The water heater appliance of  claim 11 , wherein the predetermined time interval is eight hours. 
     
     
         14 . The water heater appliance of  claim 10 , wherein the operating parameter is a speed of a compressor of the water heater appliance. 
     
     
         15 . The water heater appliance of  claim 10 , wherein the operating parameter is a cycle time of the water heater appliance. 
     
     
         16 . The water heater appliance of  claim 10 , wherein the temperature of the environment is measured at an inlet of the evaporator. 
     
     
         17 . The water heater appliance of  claim 10 , wherein the temperature of the environment is measured outside of the water heater appliance. 
     
     
         18 . The water heater appliance of  claim 10 , wherein the temperature of the environment is measured both at an inlet of the evaporator and outside of the water heater appliance.