Our house is a 2 story forced hot water system without ductwork.
Forced air system in attic.
Heat pumps and ducts are part of it too.
The 20 to 30 foot long pipes that carry the refrigerant are disguised to look like a downspout.
A two room addition on the 1st floor has limited attic space and a 4 crawl space.
It also hard to predict where exactly the new air which is replacing the air forced out by the ventilator will come from.
This drain removes the excess water that a heating system will generate.
Because the units forcefully pull air from the attic they can create depressurization in your home.
Since most homes have their hvac system serve multiple functions at once it can be cheaper to install the unit in the attic because the roof access can make inspections maintenance and repairs at lot easier.
Typically this indoor unit gets placed in a cabinet or closet somewhere inside.
Forced air systems are usually the cheapest ones to install in homes today and a furnace qualifies as this type of system.
Most updated central air conditioned homes have a new air conditioner split system meaning the ac is broken up into parts.
So why put an hvac system up in the attic at all.
A basement is below and an attic is above the main part of the house.
There are rarely instances when we will advise against an attic installation.
However i have two questions if i want to centrally air.
An outdoor unit which houses the fan condenser and compressor and an indoor unit which holds the evaporator and fan.
It s easy to see your point about eliminating ductwork from the attic.
If you don t have forced air the fan and coil system is typically placed in the attic where it will deliver cool air through ducts.