Sorry but you won't be able to control the receiver volume with the TV remote.
The only programming codes available with the RM-Y180 are for VCR/DVD and SAT/CBL components, which means no receiver codes=no receiver volume control.
A good solution would be a learning remote, such as the Sony RM-VL600/VL610 or the One For All 6820/8820 remotes. With the OneForAll you could use extended codes, described by bodhi78_rc in this thread
[Link: remotecentral.com]