Boiler & AC unit

[Ronald Ty]

Curious, why would there be a boiler unit, in the basement, & an AC unit outside with hvac vents in the main level kitchen? From what I've read, they both have to be independent of each other.

If you were going to flip the house (it would be a high end home), would you switch the boiler for forced air furnace? I would think you'd need to rip out all the boiler pipes throughout the home (it's a tri level). 

Or are there other options?
 

[Clayton Boyle]

I personally like hot water heating and would keep the boiler installation as-is as long as it's still viable. The expense of moving over to forced air heating wouldn't be in the removal of the radiators (baseboard or otherwise) but in adding the proper ducting throughout the house for the new furnace.  A new boiler install into an existing system is also expensive but less destructive and messy. Depending on how deep you are getting into the house during the flip, it might not be that much more invasive to run new ducting, or it could be a real pain in the butt. 

People will have separate AC installs when running radiant heating b/c you obviously cannot use the boiler system to cool the house. Mini splits are a common solution to cooling houses that don't have forced air systems - they are very efficient and give you the ability to cool specific rooms and zones individually.