I've been talking to some air condition installers and I cannot understand why they want to put in so heavy units.
My house, which is not yet constructed, is a 4 floor building each about 600 sq feet.
First floor has kitchen and garage. The garage is "outside"
Second floor has a small office, bathroom and the living room, which is totally open to the hallway
Third floor has two bedrooms and a bathroom.
Fourth floor is identical to the third floor.
Fifth floor only has an exit to the roof.
The southern part of the roof is flat.
The northern part is covered with a roof.
There are only windows on the south side wall.
The north side gets its light from a 10 feet x 8 feet skylight going down all floors.
I live in Ho Chi Minh, Vietnam. Climate info
I estimated that I needed about 75CFM fresh air per floor, which is done via a heat exchange unit on the fifth floor.
Trane's first suggestion was 125.000 BTU for the whole house.
Trane's second and rather more detailed suggestion wants a 24.000 BTU unit on each floor (96.000 BTU in total) and do 600CFM whole house ventilation with about 200CFM being exchanged with fresh air.
Reetech wants to put a 24.000 BTU, a 32.000 BTU, 3 x 12.000 BTU, and 2 x 18.000 BTU units in, totaling 128.000 BTU.
LG I just talked to on the phone, but they also quoted around 120.000 BTU.
If I try to use the HVAC-calc residential 4.0 I end up at just 43.000 BTU for the whole house with no insulation and only 26.000 BTU with minimal insulation. I attached the reports to the post.
Can someone help me determine what is the right answer?