Method of announcing replacement time of air filter in a heating, ventilating, and air-conditioning system of a vehicle

Abstract

A method for announcing the replacement time of an air filter in an HVAC system of a vehicle includes the steps of inputting factors used for judging whether the air filter should be replaced; determining whether inside air or outside air is supplied; calculating a total amount of dust by calculating a dust concentration reduction per unit volume by considering a total amount of introduced air and an initial inside dust concentration if inside air is supplied, or calculating a total amount of dust using an amounts of air at a current operation level if outside air is supplied; determining whether the total amount of dust exceeds a reference amount of dust; and activating an indicator, such as an alarm or a warning light, if the total amount of dust exceeds the reference amount of dust.

1 . A method of announcing the replacement time of an air filter in a heating, ventilating, and air conditioning system of a vehicle, comprising the steps of: 
 inputting factors used for judging whether the air filter must be replaced;    determining whether inside air or outside air is supplied;    calculating a total amount of dust, the calculating a total amount of dust comprising: 
 if inside air is supplied, calculating a dust concentration reduction per unit volume by considering a total amount of introduced air and an initial inside dust concentration; and  
 if outside air is supplied, calculating the total amount of dust using an amount of air at a current operation level and an air direction;  
   determining whether the total amount of dust exceeds a reference amount of dust; and    activating an indicator if the total amount of dust exceeds the reference amount of dust.    
   
   
       2 . The method as defined in  claim 1 , wherein the factors comprise a regional pollution level, an air filter type, and a passenger compartment volume of the vehicle.  
   
   
       3 . The method as set forth in  claim 1 , wherein the step of calculating the total amount of dust further comprises using a preset amount of air if a blower motor is not driven and outside air is supplied.  
   
   
       4 . The method as set forth in  claim 3 , wherein the preset amount of air is approximately 60 cubic meters per hour.  
   
   
       5 . The method as set forth in  claim 1 , wherein the total amount of introduced air V is calculated from V=Q H, where Q is an amount of air introduced per unit time, and H is time.  
   
   
       6 . The method as set forth in  claim 1 , wherein the total amount of dust W on the air filter is calculated from W=V C, where V is a total amount of introduced air, and C is a concentration of dust.  
   
   
       7 . The method as set forth in  claim 1 , further comprising the step of: 
 storing the total amount of dust on the air filter if the total amount of dust on the air filter does not exceed the reference amount of dust.