The best brand is one for which parts and service are, and will continue to be readily available in your area. A local professional contractor can help you make an informed choice about which is most appropriate to your needs and budget. Make sure to choose an HVAC contractor who is registered with your local building dept., pulls the required permit, and gets the work inspected.

In my honest opinion there currently is no "best brand" right now. All brands are fairly equal at the low end efficiency range.

Going to 2 speed AC is more costly may require full system replacement including your furnace and the payback while better than single speed isn't really where the market is going.

Inverter... the cream of the crop. Can cut your electric bills by up to 50%. However inverter AC can vary quite a bit from manufacturer to manufacturer. Most major mfgs, will require expensive proprietary controls.

The Bosch Inverter came to H-town market in 2019. Bosch does things differently than the major mfgs. It has proven itself well this past year for me and the customers I have that chose it. Last year was a really hot summer here.

I install more brands than just Bosch. There are some that print misinformation because they have signed contracts with brands that can't do what Bosch does.

There are gotchya's coming in the near future. R410a refrigerant for equipment we are selling now is in the cusp of being phased down and out. While this will take time, the cost of refrigerant will likely jump in price as early as next year due to production cuts.

2025 will likely be the start of a new R410a equipment ban. The good news is you still have a choice. The bad news is if your equipment springs a refrigerant leak in the years to come will make the repair more expensive. However, because AC equipment can last upto 15 years and in some cases longer... you may skip a generation of equipment.

The new refrigerants & equipment will likely show up some time in 2024. I have a lengthy informational discussion in video content on my main website that discusses all the pros and cons. Click here.

I service the Katy, Texas area.

I was wondering what do you recommend for the replacement brand and capacity.

I suggest you see what brands are popular in your area and then research who are the best HVAC installers. Carrier, which is also the same equipment as Bryant, would not be a bad choice. But if the local Carrier dealers have bad reputations, then you need to find another brand.

The capacity of the AC equipment is determine by the cooling load of your house. A good installation starts with a heating and cooling load calculation. You want to make sure the proper size is being installed. An equipment that is too big in humid climates is worse than equipment which is too small. If the house has had modifications in the past 16 years, then the 3.5 ton size may no longer be correct.

2006 was around the time everyone was changing over to R410a from R22. If your unit was R22, you will need to change the coil also (and possibly the lineset). Get someone in to check the system out (get at least 3 quotes). Brand is pretty unimportatnt but if you have a prefered company, use whatever they recommend.

Thank you all! Very helpful tips. Much appreciated.

Have you taken steps to reduce AC demand such as caulking, insulating, shading windows, etc? My condo was impossible to cool until I added window film to a large skylight through which the sun blasted during the summer. Take a look at energystar.gov for ideas. Of course, the AC unit may still need replacement.