I've attached a PDF image of a diagram of my house, which is in SW Arizona. The problem is the very front room, which is actually an enclosed garage. The house was like this when I bought it almost 20 years ago.
The AC unit is located at the very back of the house - it's a single package unit with gas heat setting on the ground. It's a 4-plus-ton unit, about 15 years old. It works great to cool the house - except the front room. The previous owners had run 12-inch diameter flex duct through the attic into the front room (total about 35 feet long), and the AC fan just can't push the air that far. Finally, realizing I had a duct in the attic full of cold air that wasn't getting into the rest of the house, I disconnected the duct and blocked off the tee from the main trunk.
The room is now blocked off with heavy curtains; otherwise, the uncooled air in that room migrates back into the rest of the house. As shown in the diagram, this hot air first hits the living room. The dining room and living room (which are actually one undivided room) are fed cool air by the one last vent in the end of the AC duct. And it's hardly enough to cool that off (the same vent also has to cool off the dining room). The hot air in the front room is one issue. Other factors are: the house was built in 1954 and is not well insulated, and in the living room is a large (4' high x 6' wide) single-pane window facing east. (Yes, the window has to go, but it won't solve the poor AC problem.)
I'm now at a place where I can address this hot room and make it livable. The question is which option to take?
-- A mini-split for just that room (234 sq ft)
I'm sure this would be the cheapest option, both the purchase and the installation cost.
-- A small second AC for the living room and the front room (total about 580 sq ft)
A split unit with the air handler in the attic and the outflow split to cover both rooms. The advantages here are: this helps the main AC cool the undivided dining/living room; I can pipe in natural gas from the fireplace for heat.
What other options and / or issues are there that I am not seeing?
How would you advise in this situation?
Ed
The AC unit is located at the very back of the house - it's a single package unit with gas heat setting on the ground. It's a 4-plus-ton unit, about 15 years old. It works great to cool the house - except the front room. The previous owners had run 12-inch diameter flex duct through the attic into the front room (total about 35 feet long), and the AC fan just can't push the air that far. Finally, realizing I had a duct in the attic full of cold air that wasn't getting into the rest of the house, I disconnected the duct and blocked off the tee from the main trunk.
The room is now blocked off with heavy curtains; otherwise, the uncooled air in that room migrates back into the rest of the house. As shown in the diagram, this hot air first hits the living room. The dining room and living room (which are actually one undivided room) are fed cool air by the one last vent in the end of the AC duct. And it's hardly enough to cool that off (the same vent also has to cool off the dining room). The hot air in the front room is one issue. Other factors are: the house was built in 1954 and is not well insulated, and in the living room is a large (4' high x 6' wide) single-pane window facing east. (Yes, the window has to go, but it won't solve the poor AC problem.)
I'm now at a place where I can address this hot room and make it livable. The question is which option to take?
-- A mini-split for just that room (234 sq ft)
I'm sure this would be the cheapest option, both the purchase and the installation cost.
-- A small second AC for the living room and the front room (total about 580 sq ft)
A split unit with the air handler in the attic and the outflow split to cover both rooms. The advantages here are: this helps the main AC cool the undivided dining/living room; I can pipe in natural gas from the fireplace for heat.
What other options and / or issues are there that I am not seeing?
How would you advise in this situation?
Ed