>Why is it that the first line returns a blank and the second line returns a value?
>
>Thermo.lnPerc.Caption = Str(Thermo.lnCurrent) + "A"
>
>Thermo.lnPerc.Caption = Str(Thermo.lnCurrent)

I'm not using VB much, but as I know VB uses '&' instead of '+' to concatenate strings.