Two considerations: Excess Heat & Carbon Fouling.
You probably would need to build an "improper fire" ie hotter than it should be, and measure how much heat is in the area you want to mount the unit.
The issue with carbon fouling or other pollution aspects will occur when the fireplace doesn't draft properly. Very importnat to have excess makeup air to help the chimne draft properly. Weather conditions can still cause problems however. Even with a gas fireplace you will be dealing with trace amounts of sulfuric acid pollution. Thats why gas appliances require stainless steel or galvanized steel liners.
While the location may be aesthetically interesting, I think from a long term viewpoint this is an inappropriate location for any electronics.
You probably would need to build an "improper fire" ie hotter than it should be, and measure how much heat is in the area you want to mount the unit.
The issue with carbon fouling or other pollution aspects will occur when the fireplace doesn't draft properly. Very importnat to have excess makeup air to help the chimne draft properly. Weather conditions can still cause problems however. Even with a gas fireplace you will be dealing with trace amounts of sulfuric acid pollution. Thats why gas appliances require stainless steel or galvanized steel liners.
While the location may be aesthetically interesting, I think from a long term viewpoint this is an inappropriate location for any electronics.