That machine with 21% space on /var left, is an (to be retired for hw reasons) auxilary backup file server 
running Debian Wheezy.
FreePBX machine is a Completely Different Machine and not even in the same room running Freepbx distro.
The FreePBX machine has
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/md2 72G 20G 49G 29% /
tmpfs 499M 0 499M 0% /dev/shm
/dev/md0 291M 32M 245M 12% /boot
(this is default as FreePBX distro partitioned it while installing back in November… )