ADC math won't cooperate?? why??

 Function sensor() As Word
    result = (ADC.Read(0)+1) *5000 / 1024*1023/5*1.41-42.51  
    End Function

 Function sensor() As Word
    result = (ADC.Read(0)*1023)/ 5 *81-45//1024 is divide by  tip sensor  0.07 at RT .25 melt
     //1024 is divide by  temp ref desired
    End Function

 Function sensor() As Word
    result = (ADC.Read(0)*1023)/ 5 *(81/1000)-45//1024 is divide by  tip sensor  0.07 at RT .25 melt
     //1024 is divide by  temp ref desired
    End Function

 Device = 18F4520
    Clock = 8
    // some LCD options...
    #option LCD_DATA = PORTD.4
    #option LCD_RS = PORTD.2
    #option LCD_EN = PORTD.3
    // uses LCD and AD libraries...
    Include "LCD.bas"
    Include "ADC.bas"
    Include "convert.bas"
    Include "InternalOscillator.bas"
    Include "math.bas"
    Dim ADVal As Word
    Dim LED_g As PORTC.0
    Dim LED_r As PORTC.1
    Dim opti As PORTE.0
    //Dim Vref, Vsensor As longWord
    Dim Vref, Vsensor As Integer
    //Dim tiptemp As Integer
    // Read the AD port and scale for 0.00 - 5.00 volts...
    Function REF_V() As Word
    result = (ADC.Read(1)+1)*5000/1024   //1024 is divide by  tip sensor
    End Function
    Function sensor() As Word
    result = (ADC.Read(0)*1023)/ 5 *(81/1000)-45//1024 is divide by  tip sensor  0.07 at RT .25 melt
     //1024 is divide by  temp ref desired
    End Function

    // Start Of Program...
    Input(PORTA.0)                  // temp ref voltage desired temp
    Input(PORTA.1)                  // tip sensor
    Low (LED_g)                     //set lEDs OFF
    Low (LED_r)
    High(opti)
    ADCON1 = %10000000              //set up ADC regesters
    ADCON0.7 = 1
    ADCON0.6 = 1

    DelayMS (150)
    LCD.Cls
       


        // main program loop...
        While true
            // call function REF_V() and assign the result to word variable 'Vref'
            Vref = REF_V()                // desired temp
            LCD.MoveCursor (1,1)
            LCD.Write("REF_V = ", DecToStr(Vref/100), ".", DecToStr(Vref, 2), " ")
            DelayMS(250)
           
           
            // call function sensor() and assign the result to word variable 'Vsensor'
            Vsensor = sensor()          // tip sensor
            LCD.MoveCursor (2,1)
            LCD.Write("sensor = ", DecToStr(Vsensor/100), ".", DecToStr(Vref, 2), " ")
            DelayMS(250)
           
            // compare Vsensor and Vref values
            If Vsensor < Vref Then      // not hot enough
                LED_r=1
                LED_g=0
                opti=0                  // turn on opti couplier by going low
            Else                        // Vsensor must be >= Vref, so desired temperature
                LED_g=1
                LED_r=0
                opti=1                  // turn off opti couplier by going high
            End If
        Wend