Hvac efficiency boosting fan system, apparatus and method

Abstract

A booster fan system for a duct network connected to an HVAC unit includes: (a) a booster fan unit installable in the duct network adjacent a duct register, the booster fan unit including at least one blower and at least one temperature sensor; and (b) a control system for controlling operation of the at least one blower based on a prediction model configured for estimating an operational state of the HVAC unit based on sensor data received from the temperature sensor and the operational state determined for the HVAC unit during preceding HVAC cycles.

1 . A booster fan system for a duct network connected to an HVAC unit, comprising:
 a) a booster fan unit installable in the duct network adjacent a duct register, the register open to a room for climate control via the HVAC unit, the booster fan unit including at least one blower for moving air between the room and the duct network through the register and at least one temperature sensor for monitoring temperature adjacent the register; and   b) a control system for controlling operation of the booster fan unit, the control system including at least one processor configured to:
 i) continuously receive sensor data from the at least one temperature sensor relating to the temperature adjacent the register; 
 ii continuously determine an operational state of the HVAC unit using a prediction model configured for estimating a current operational state of the HVAC unit based on the sensor data and the operational state determined for the HVAC unit during preceding HVAC cycles; and 
 for each HVAC cycle, update the prediction model with the current operational state predicted for the HVAC unit for that HVAC cycle; and 
 iv) control operation of the blower of the booster fan unit during each HVAC cycle based at least in part on the operational state determined for the HVAC unit for that HVAC cycle. 
   
     
     
         2 . The system of  claim 1 , wherein the prediction model is configured to identify the current operational state from the sensor data, and confirm the current operational state identified from the sensor data based on the operational state determined for the HVAC unit during the preceding HVAC cycles. 
     
     
         3 . The system of  claim 2 , wherein the prediction model is configured to confirm the operational state from the sensor data based on a prediction history average of the operational state predicted for the HVAC unit during the preceding HVAC cycles. 
     
     
         4 . The system of  claim 3 , wherein the prediction history average comprises a moving average. 
     
     
         5 . The system of  claim 4 , wherein the prediction history average corresponds to a prediction history sum for the preceding HVAC cycles divided by a total number of the preceding HVAC cycles accounted for in the prediction history sum. 
     
     
         6 . The system of  claim 5 , wherein the prediction history sum is adjusted by a constant for each preceding HVAC cycle for which the heating cycle state was determined, and oppositely adjusted by the constant for each preceding HVAC cycle for which the cooling state was determined. 
     
     
         7 . The system of  claim 1 , wherein the preceding HVAC cycles considered by the prediction model are limited to HVAC cycles with a duration exceeding a predefined time period. 
     
     
         8 . The system of  claim 7 , wherein the predefined time period is at least  5  minutes. 
     
     
         9 . The system of  claim 1 , wherein the prediction model is configured to identify the current operational state as a heating cycle state if the sensor data indicates the heating cycle state and as a cooling cycle state if the sensor data indicates the cooling cycle state. 
     
     
         10 . The system of  claim 9 , wherein the sensor data indicates the heating cycle state if a current temperature is greater than a sum of a heating tolerance parameter and a prior temperature measured at a predetermined time interval prior to the current temperature, and the prior temperature is greater than a heating threshold; and the sensor data indicates the cooling cycle state if the current temperature is greater than a sum of a cooling tolerance parameter and the prior temperature, and the prior temperature is less than a cooling threshold. 
     
     
         11 . The system of  claim 1 , wherein the booster fan unit further includes at least one vibration sensor for monitoring vibrations in the duct network adjacent the register, and the prediction model is configured to estimate the current operational state of the HVAC unit based further on sensor data received from the vibration sensor relating to the vibrations in the duct network adjacent the register. 
     
     
         12 . The system of  claim 1 , wherein the control system is integrated into the booster fan unit. 
     
     
         13 . A booster fan system for a duct network connected to an HVAC unit, comprising:
 a) a booster fan unit installable in the duct network adjacent a duct register, the register open to a room for climate control via the HVAC unit, the booster fan unit including at least one blower for moving air between the room and the duct network through the register and at least one temperature sensor for monitoring temperature adjacent the register; and   b) a control system for controlling operation of the booster fan unit, the control system including at least one processor configured to:
 i) continuously receive sensor data from the at least one temperature sensor relating to the temperature adjacent the register; 
 continuously determine an ambient temperature in the room using a prediction model configured for estimating a current ambient temperature in the room by applying the sensor data to a temperature model correlating the temperature adjacent the register to the ambient temperature in the room during and between HVAC cycles of the HVAC unit; and 
 iii) control operation of the blower of the booster fan unit based at least in part on the ambient temperature determined for the room. 
   
     
     
         14 . The system of  claim 13 , wherein the temperature model is generated based at least on the sensor data received from the temperature sensor following termination of each of a plurality of previous HVAC cycles of the HVAC unit. 
     
     
         15 . The system of  claim 14 , wherein each previous HVAC cycle of the plurality of HVAC cycles comprises a qualifying HVAC cycle preceded by another HVAC cycle by at least a predefined first time period and followed by another HVAC cycle by at least a predefined second time period. 
     
     
         16 . The system of  claim 15 , wherein the first time period is 90 minutes and the second time period is 30 minutes. 
     
     
         17 . The system of  claim 15 , wherein the plurality of previous HVAC cycles include at least three qualifying HVAC cycles. 
     
     
         18 . The system of  claim 14 , wherein the temperature model comprises a first statistical model generated for the plurality of previous HVAC cycles based on temperature measurements taken by the temperature sensor during a predetermined first time period following termination of each previous HVAC cycle, and a second statistical model generated for the plurality of previous HVAC cycles based on temperature measurements taken by the temperature sensor during a predetermined second time period following the first time period and prior to a subsequent HVAC cycle. 
     
     
         19 . The system of  claim 18 , wherein the first time period is 30 minutes and the second time period is 60 minutes. 
     
     
         20 . The system of  claim 14 , wherein the temperature model comprises one or more linear regression models.