hopebox:The temperature setting in CodeV is 25C and in ZEMAX is 20C. 
In addition, in CodeV, dn/dt table is used as default. However, there is a macro in CodeV you can make use of  the index thermal coefficients to set index at 20C. (You can check the user  ..
 (2015-05-19 23:23)  )2Bb,p<Wr
 )2Bb,p<Wr