Access to webserver inside lan from wan

[wompy]

hi this is kind of a weird question. our HVAC unit has a local static ip of 192.168.2.130, but its interface is 192.168.2.130/metasys
That is where the problem begins. I setup NAT and portforwarding to send http (80) traffic to 192.168.2.130 but all I get is a server timeout. The problem is that it only resonds when the "/metasys" is there. Are there any ideas on how to set this up? I still have 4 WAN static IPs available if that helps.

-thanks