I have a 2 story single family home , total HLA 1400-1700. I’ve lived in the house for almost 3 ½ years. The first floor has high ceilings. During the summer I can never get the temperature indoors below 20, 10, nor 5 degrees lower than the temperature outdoors. My a/c is 13 years old. My home warranty sends a tech, and each time they say it's low on freon. I've been told there are no leaks. There isn't any frost. The outside unit is functioning properly. The filters are new. The tech’s only comment, the unit must be too small. It’s still hot in here! Help! What else can be checked by the tech that might have been missed?

Sounds like size is a problem, or lack of airflow. Maybe not enough returns

Freon doesn't just disappear. How can it be low on freon each time but "no leaks ". What is the tonnage and does it cool better at night?

[QUOTE=ma0641;3514327]Freon doesn't just disappear. How can it be low on freon each time but "no leaks ". What is the tonnage and does it cool better at night?

Tonnage is 3 tons. Never use the a/c at night. I will tonight , because a tech is coming tomorrow to check it. He has already informed me that it might need freon before he has even checked it. No surprise there!

sounds like size is a problem, or lack of airflow. maybe not enough returns I hope it's not size. As for returns... airflow, I'll be sure to question it.

As I stated before, if you need Freon every time, you have a leak. 3 tons sounds a bit low for the size of the house. 3 ton would be for about 1800-2000 sq. ft. house, average of 1 ton per 600 sq. ft. Not an exact science to get there but a start. High ceilings means you need to heat and cool a lot of cubic ft of air. Where is air handler, in the attic? A lot depends on sun loading, insulation, windows, how the house faces, where you live, ambient temp, average humidity, etc. Have a Manual J done. .

As ma0641 said, if you need refrigerant every time, you have a leak. Air conditioners do not consume refrigerant. It just goes from a vapor to a liquid to a vapor, over and over all within a sealed system.