|There's nothing I see in your setup that would prevent you SSH'ing into the HTPC from your wirelessly connected client. |
Since both computer are connected to your router, the traffic between them never leaves your LAN.
I'm more inclined to think the source of the issue is the HTPC computer. If it's running a windows based operating system, check to ensure the built in firewall is turned off and then try again. You also have to have an SSH service running on that box in order have something to connect to.
If it's a Linux box, ensure you have SSH enabled on it.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.