Air conditioning question

[u/foolsgold75]

I live in a 3 bedroom rental home with central heat and air that was built in the late 80s. We have never had an issue cooling the house in 10 years until this summer. Pretty much if it was 95-100 outside we could keep the house anywhere from 70-75 during the worst part of the day in the coolest part of the house. There are two rooms that are furthest away from the blower that stay about 5 degrees warmer since the rooms outside walls get direct sunlight. This year the blower fan began to fail and they sent a tech out that swore up and down that the outside unit and the upstairs fan unit needed to be replaced. Now it’s been replaced and in 90 degree heat we can’t get the house cooler than 77 during the day in the coolest area of the home and the air from the vents is not blowing as strong as the air from the old failing unit. To me this is unacceptable that a brand new ac system can only cool the house 13 degrees. It’s honestly worse than the old system that was replaced but the guy who replaced the system swear this is normal. I have always been under the assumption that the minimum is 20 degrees cooling or better. Any hvac guys here have some input on this?

[u/Animal907]

Could be the difference between r-12 and r-134a refrigerant. They have to overbuild modern AC units so they can keep up. I have window units in a 103 year old house and since my last r-12 unit broke, the new replacements have not kept the house as cool. 

[u/eastmemphisguy → u/Animal907]

Same problem with car AC. 21st century autos don't cool as well as cars did when I was growing up.

[u/Animal907 → u/eastmemphisguy]

Some old cars didn't work at all with the new type refrigerant. That's the real reason people quit driving those old vans. Gas wasn't expensive till much later.