I bought a Spec home about a year ago and started to have cooling problems from day one. Its a two story house with the bedrooms and my office upstairs. They installed a 3 ton carrier unit and 2 zones with a furnace. Now that the hot days are back the unit can’t keep up with demand. The upstairs stays around 74 in the am but around 5:00 pm its 80 degree or higher. The contractor came out and looked at it and told me that if it is 95 degrees outside that the inside temp of 80 degrees is normal and kept throwing the Manual J up. I know that the Manual J is a standard but I have worked for the company that installed the system and they never did Manual J. It was the rule of thumb. I live in South Carolina the home is around 2800 sqft. I really would like some guidance in how to handle this issue because having a bedroom at 80 degrees is no fun.
Thanks for any advice you can give.