Unit: 3 ton Carrier (AC only)
Home: 1400 sq/ft
Cooling area: 940 sq/ft
I bought my house September last year and have not needed to turn on my AC until now. I noticed that it runs for a very long time when attempting to cool the house. Yesterday it was 90F outside so I turned my AC on when I returned from work at 3:30p at which time it was 80F in the house. At 8:00p the unit had not cut off and only cooled the house 3F, making it 77F inside. I checked the air temperature at all registers and it was 43F. Air temp at return was 67F. The seller of the home advertised "New duct work." A lot of things around the house seem like they were done by non-professionals, including the duct work. There are 10 registers throughout the house, all with 6" duct. My cousin is HVAC certified and seems to think that I need to add 6 more registers throughout the house to solve the problem. The vents seem to be blowing really cold air with not much force. I'd like a second opinion before I go cutting more holes in my floor.
Today is 86F outside. With the thermostat set to 74, it takes an hour of running time to cut itself off. I'm afraid of my power bill being too high, especially in the middle of summer.