Gas and Oil Home Heating Furnaces - Mis-Match Split System

My split system is comprised of a Carrier Air Handler (inside) model HOAQ030330EH approximately 20 years old and s Comfort Range condensor (outside) model SB3A-036K built in 2000. I don't feel it's been cooling my home efectivelt. I've had it inspected several times sinc epruchasing my home in September 2000. I've been told by two contractors the system is mismatched. Inside is a 2.5 ton unit and outside is a 3 ton. Another has told me the size difference is within industy acceptable limits.
He also told me the coils on the inside are beyond repair. One of the service techs that stated the system is mismatched has confirmed this. But does not agrees that the 1/2 ton difference is acceptable.
I want to repair this. I can try to repair what is there or replace with new larger unit.
Can you confirm that combining a 3 ton condensor with a 2.5 ton handler/insdie coil is acceptable?
Or, direct me to some type od industry association guidlines?
Thanks,
Tyson110

If it is true the inside coil is beyond repair, all that's needs to be done is replace the coil. The air handler for a 2 and 1/2 ton and 3 ton unit are usually the same size. So if you are able to find some one that will replace the coil, do it with a 3 ton. My advice to you is go to a vocational school for HVAC and speak to an instructor. Tell him your problem and ask if he would like to give his students some hands on experience. Tell him you'll pay for all the parts he recommends be replaced and in return for the installation you'll donated a tool or tools of comparible value for labor to the school's workshop. You get what you want, so does the students, instructor and school.