I have an odd question that I was thinking about last night. I currently have a split heat pump system for the first floor of our house. The system is just a tad bit undersized at 2 tons.
Is it possible I could replace the blower motor with a higher rpm/cfm motor if the voltage, etc...are within the required specs of the board and get more air?
It would put out more air but would it work? I just need to get the system up to about 2.25-2.5 tons and I was wondering if anyone had done or heard of this before. The air handler is a gibson 2 ton and the outside condenser is a 2 ton grand aire.
Many of the air handlers are designed to work with a range of capacities. Some have 3 speeds or even more on the blowers that are configurable either through DIP switches, jumpers, or moving wires around on the circuit boards. Turn off power to your AHU, and then take the cover off. THere's probably a spec sheet or a sticker somewhere indicating how to change speeds on the blower.
I will mention though that this will NOT give you extra cooling / heating capacity. It may make the system a little bit more efficient when you turn up the blower speed, and it may help distribute the air more evenly throughout your house, but it's probably not going to do much for higher cooling/ heating capacity. The outdoor unit is what makes the capacity for the system, and it will need to be upgraded to get more cooling power. If you can get your hands on the same make outdoor unit, you may not need to replace the air handler, just turn up the fan speed to meet the spec of the larger outdoor unit.
Your cooling trouble is probably more related to your duct system, then the size of your A/C. that model air handler has a very low performing blower. remove your air filter, and see if it blows out more air.