Changed root password but still can not login with su

I'm currently using FreeNAS 11.2-U7

I changed root password through login console.

After change, I login to main FreeNas installation as regular user.

I then type:

su

and then type password (same password as entered above)

I then get:

su: Sorry

On console I get the following:

freenas su: BAD SU kevdog to root as /dev/pts/0

kevdog = My username