The furnace is an older model Carrier. I do not know at this time the exact model. It is at this time about 20 years old.
The central air is a newer Carrier Performance series model. It is two years old.

I have checked to make certain the blower moves freely; it does.

The blower in the furnace works when the heat is turned on. However, when switched to cooling, the blower does not go on. I have repeated going between heating and cooling. Each time the blower will turn on when switched to heat, but will not when switched to cool.

I believe the problem is electrical, either the fan relay or capacitor, but I am uncertain of how to proceed.

Would someone please offer some advice? Thanks, I do appreciate it!