Systems and methods for controlling indoor humidity

Abstract

Methods and related systems for controlling indoor relative humidity are disclosed. In an embodiment, the method includes (a) determining a target dew point temperature based on desired indoor conditions for the indoor space, and (b) determining an initial dew point temperature based on an initial set of current indoor conditions of the indoor space. In addition, the method includes (c) determining a target coil temperature of a coil of an indoor heat exchanger of the climate control system based on the target dew point temperature and the initial dew point temperature, and (d) adjusting a speed of air flowing across the coil or a speed of a compressor of the climate control system after (c) based on the target coil temperature to reduce a difference between a coil temperature of the coil and the target coil temperature.

1 . (canceled) 
     
     
         2 . A method of operating a climate control system that includes HVAC equipment configured to provide conditioned air to an indoor space, the method comprising:
 determining a target dew point temperature based on desired indoor conditions for the indoor space;   determining an initial dew point temperature based on an initial set of indoor conditions of the indoor space;   determining an updated dew point temperature based on an updated set of indoor conditions of the indoor space;   determining a dew point error based on a difference between the target dew point temperature and the updated dew point temperature;   setting, during a cooling mode, a target coil temperature of a coil of an indoor heat exchanger of the climate control system based on a difference between the target dew point temperature and the initial dew point temperature;   adjusting, during the cooling mode, the target coil temperature to an adjusted target coil temperature, in part, using a proportional and integral control loop that utilizes the dewpoint error as a feedback; and   adjusting, during the cooling mode, a component of the HVAC equipment based on the adjusted target coil temperature, to reduce a difference between a coil temperature of the coil and the adjusted target coil temperature.   
     
     
         3 . The method of  claim 2 , wherein the component of the HVAC equipment includes at least one of an indoor fan and a compressor. 
     
     
         4 . The method of  claim 2 , wherein adjusting the component of the HVAC equipment includes:
 decreasing the speed of air flowing across the coil of the indoor heat exchanger to a predetermined minimum speed of the indoor fan of the climate control system.   
     
     
         5 . The method of  claim 4 , wherein adjusting the component of the HVAC equipment includes:
 determining the coil temperature is above the target coil temperature after decreasing the speed of air flowing across the coil to the predetermined minimum speed; and   further increasing the speed of the compressor based on the determination of the coil temperature.   
     
     
         6 . The method of  claim 2 , wherein determining the coil temperature is based on a measurement of the refrigerant pressure. 
     
     
         7 . The method of  claim 2 , wherein the steps of determining the updated dew point and adjusting the target coil temperature are each repeated a plurality of times during the cooling mode to repeatedly adjust the target coil temperature, each of the plurality of times establishing an updated adjusted target coil temperature. 
     
     
         8 . The method of  claim 2 , wherein the proportional and integral control loop is a first proportional and integral control loop, and
 wherein adjusting the component of the HVAC equipment includes, in part, using a second proportional and integral control loop.   
     
     
         9 . A climate control system for an indoor space, the climate control system comprising:
 a heat exchanger, comprising a coil to flow refrigerant therethrough;   a fan configured to flow air over the coil;   a compressor configured to compress refrigerant that is to be flowed through the coil; and a controller coupled to the indoor fan and the compressor, wherein the controller is configured to:
 determine a target dew point temperature based on desired indoor conditions for the indoor space; 
 determine an initial dew point temperature based on an initial set of indoor conditions of the indoor space; 
 determine an updated dew point temperature based on an updated set of indoor conditions of the indoor space; 
 determine a dew point error based on a difference between the target dew point temperature and the updated dew point temperature; 
 set, during a cooling mode, a target coil temperature of a coil of an indoor heat exchanger of the climate control system based on a difference between the target dew point temperature and the initial dew point temperature; 
 adjust, during the cooling mode, the target coil temperature to an adjusted target coil temperature, in part, using a proportional and integral control loop that utilizes the dewpoint error as a feedback; and 
 adjust, during the cooling mode, a component of the HVAC equipment based on the adjusted target coil temperature, to reduce a difference between a coil temperature of the coil and the adjusted target coil temperature,
 wherein the component of the HVAC equipment includes at least one of an indoor fan and a compressor. 
 
   
     
     
         10 . The climate control system of  claim 9 , wherein the controller configured to adjust the component of the HVAC equipment is further configured to:
 decrease the speed of air flowing across the coil of the indoor heat exchanger to a predetermined minimum speed of the indoor fan of the climate control system.   
     
     
         11 . The climate control system of  claim 10 , wherein the controller configured to adjust the component of the HVAC equipment is further configured to:
 determine the coil temperature is above the target coil temperature after decreasing the speed of air flowing across the coil to the predetermined minimum speed; and   further increase the speed of the compressor based on the determination of the coil temperature.   
     
     
         12 . The climate control system of  claim 9 , wherein determining the coil temperature is based on a measurement of the refrigerant pressure. 
     
     
         13 . The climate control system of  claim 12 , further comprising a sensor located between the heat exchanger and the compressor, the sensor operably coupled to the controller and configured to provide the controller the measurements of the refrigerant pressure. 
     
     
         14 . The climate control system of  claim 9 , wherein the controller is further configured to perform the steps of determining the updated dew point and adjusting the target coil temperature each repeatedly a plurality of times during the cooling mode to repeatedly adjust the target coil temperature, each of the plurality of times establishing an updated adjusted target coil temperature. 
     
     
         15 . The climate control system of  claim 9 , wherein the proportional and integral control loop is a first proportional and integral control loop, and
 wherein the controller configured to adjust the component of the HVAC equipment is further configured to adjust the component of the HVAC equipment, in part, using a second proportional and integral control loop.   
     
     
         16 . A controller for operating a climate control system, the controller comprising:
 a memory configured to store computer-readable program code including a control-related software application; and
 a processor configured to access the memory, and execute the computer-readable program code to cause the processor to at least: 
   determine a target dew point temperature based on desired indoor conditions for the indoor space;
 determine an initial dew point temperature based on an initial set of indoor conditions of the indoor space; 
 determine an updated dew point temperature based on an updated set of indoor conditions of the indoor space; 
 determine a dew point error based on a difference between the target dew point temperature and the updated dew point temperature; 
 set, during a cooling mode, a target coil temperature of a coil of an indoor heat exchanger of the climate control system based on a difference between the target dew point temperature and the initial dew point temperature; 
 adjust, during the cooling mode, the target coil temperature to an adjusted target coil temperature, in part, using a proportional and integral control loop that utilizes the dewpoint error as a feedback; and 
 adjust, during the cooling mode, a component of the HVAC equipment based on the adjusted target coil temperature, to reduce a difference between a coil temperature of the coil and the adjusted target coil temperature, 
 wherein the component of the HVAC equipment includes at least one of an indoor fan and a compressor. 
   
     
     
         17 . The controller of  claim 9 , wherein the processor configured to adjust the component of the HVAC equipment is further configured to:
 decrease the speed of air flowing across the coil of the indoor heat exchanger to a predetermined minimum speed of the indoor fan of the climate control system.   
     
     
         18 . The controller of  claim 10 , wherein the processor configured to adjust the component of the HVAC equipment is further configured to:
 determine the coil temperature is above the target coil temperature after decreasing the speed of air flowing across the coil to the predetermined minimum speed; and   further increase the speed of the compressor based on the determination of the coil temperature.   
     
     
         19 . The controller of  claim 9 , wherein determining the coil temperature is based on a measurement of the refrigerant pressure. 
     
     
         20 . The controller of  claim 9 , wherein the processor is further configured to perform the steps of determining the updated dew point and adjusting the target coil temperature each repeatedly a plurality of times during the cooling mode to repeatedly adjust the target coil temperature, each of the plurality of times establishing an updated adjusted target coil temperature. 
     
     
         21 . The controller of  claim 9 , wherein the proportional and integral control loop is a first proportional and integral control loop, and
 wherein the processor configured to adjust the component of the HVAC equipment is further configured to adjust the component of the HVAC equipment, in part, using a second proportional and integral control loop.