What size unit fits a typical Dallas home?

For homes between 1,800 and 3,500 square feet, a 22kW or 24kW air cooled unit handles the load. The big draw is AC. A Dallas July afternoon is hard work for the system, and the generator needs to keep up with the air conditioning, the kitchen, lighting, and the pool pump or well. Larger homes (4,000+ square feet), multiple HVAC zones, or a generator that also needs to run an elevator move you into 26kW or above, and Cummins becomes a real option there. The free estimate includes a load calc so the unit matches the house.