Thermostat with heat and/or cool fan delays controlled by thermostat output

Abstract

A thermostat includes within its circuitry a delay signal generator for delaying the activation and deactivation of an air circulation fan for a predetermined time period after which a heater or compressor is activated or deactivated.

1 . A thermostat for energizing and de-energizing a forced air comfort system having a furnace and/or air conditioning system with a respective heater or compressor and an air circulating fan comprising: 
 means within said thermostat for receiving a demand signal and for responsively generating a first signal for energizing said heater or compressor;    means within said thermostat for generating a delay signal of a predetermined time period; and    means within said thermostat for generating a second signal for energizing said circulation fan upon the passing of said predetermined time period following the energizing of said heater or compressor.    
   
   
       2 . A thermostat as set forth in  claim 1  and further comprising: 
 means within said thermostat for generating a third signal for de-energizing said heater or compressor;    means within said thermostat for generating a off-delay signal of a predetermined time period; and    means within said thermostat for generating a fourth signal for de-energizing said circulation fan upon the passing of said predetermined time-off period following the de-energizing of said heater or compressor.    
   
   
       3 . A method of operating a forced air comfort system having a furnace and/or air conditioner system with a respective heater or compressor and an air circulation fan all of which are turned on and off by signals from the thermostat, comprising the steps of: 
 sensing a need for heating or cooling and sending a corresponding demand signal to said thermostat;    responsively generating within said thermostat a first energizing signal for energizing said heater or compressor;    in response to said energizing signal, generating within said thermostat an energizing delay signal of a desired time-on period;    waiting for said desired time-on period following the energization of said heater or compressor; and    generating within said thermostat a second energizing signal for responsively energizing said air circulation fan.    
   
   
       4 . A method as set forth in  claim 3  and including the further steps of generating within said thermostat a first de-energizing signal for de-energizing said heater or compressor; 
 in response to said de-energizing signal, generating within said thermostat a de-energizing delay signal of a desired time-off period;    waiting for said desired time-off period following the de-energizing of said heater or compressor; and    generating within said thermostat a second de-energizing signal for responsively de-energizing said air circulation fan.    
   
   
       5 . A thermostat for energizing and de-energizing a forced air comfort system having a furnace and/or air conditioning system with a respective heater or compressor and an air circulating fan comprising: 
 a first signal generator for generating a delay signal which causes the air circulation fan to be activated only after a predetermined time period following the energization of the heater or compressor.    
   
   
       6 . A thermostat as set forth in  claim 5  including a second signal generator for generating an off delay signal which causes the air circulation fan to be deactivated only after a predetermined time period following the de-energization of the heater of compressor.  
   
   
       7 . A thermostat as set forth in  claim 1  wherein said forced air comfort system is a furnace and said circulation fan is turned on a predetermined time after said heater is energized.  
   
   
       8 . A thermostat as set forth in  claim 1  wherein said forced air comfort system is an air conditioner and said circulation fan is turned on a predetermined time after said compression is energized.