I just purchased a new home that was built two and a half years ago. The home has a two zone heating and ac system. The heating system is forced hot air, it is a hydro system. My problem is when the second floor thermastat kicks in it makes a loud ticking and knocking sound in the walls, which is right in my bedroom. This sound goes away shortly after the boiler kicks in. Any advice would be great, I hope this problem is correctable because its keeping me up at night. Thanks

Hopefully it is only air in the lines to the fan coil. If you know what you are doing you can bleed the lines if not call for On Site Service to get it squared away.

NOTE: if you are not running the heat on the second floor all the time and the pipes cool down this could also be a problem also. When we used to do those type of installs with concealed pipes we used to install a bleeder type zone valve so a bit of hot water would always flow through the lines to pervent cold start chatter.