Hi Srinivas,
Please Check the Custom Tax Code which you have cretaed for Housing Purpose is properly mapped in all the configuration table.
If the above mentioned tax code is created for HRA then have you copied from the standard HRA Tax code SHRA, SCLA, SCOA.
Also Check function INHRA which will compute the exemptions and perquisites for housing.
Also Check the HRA Exemption will be processed on wage type /114.
Regards
Saroj Hial