There is no need to substitute the entire A/C unit in order to achieve a balanced cooling in your home, and instead, you just need to substitute the A/C coil.
During the summer, the upper-story rooms are likely to be much warmer than the main areas of the cabin if you live in a 2-story house, and changing the thermostat can cause an imbalance that results in the lower levels becoming too cold plus resulting in high utility bills… A sizzling roof, sizzling air, or leaky HVAC duct can cause warm upper floors, the sizzling air rises, while the cool air settles at the bottom. A lake house with numerous stories will have satisfactory cooling on the ground level, while heat will gather in the rooms up above. The roof can absorb radiant heat from the sun plus radiate that heat into the rooms closest to the attic; and for the cool air to reach the upper floors of the house, it must travel through longer sections of HVAC duct. This can make cooling these rooms even harder if there are leaks in the HVAC duct. There is no need to substitute the entire A/C unit in order to achieve a balanced cooling in your home, and instead, you just need to substitute the A/C coil. There is nothing more you need to do however adjust the dampers in each room by opening the basement plus ground floor registers a bit less, plus as you go up, opening them up a bit more… Making sure the air filter is disinfect plus replacing it if needed can also help ensure correct airflow, then radiant heat can be reduced by installing enough insulation on the roof. The roof deck or the roof floor can be installed with insulation, depending on the roofing style. Adding mechanical ventilation to the roof can boost attic insulation. Finally, if there are problems with the heating plus air conditioning idea itself, such as low air conditioning output or leaks in the HVAC duct, you must have it all fixed by a professional heating plus air conditioning specialist.