The answer to 'what size ceiling fan installation do I need' is that the size of ceiling fan you need depends on the size of the room. As a general guideline, you'll want a 36-inch ceiling fan for rooms up to 144 square feet, a 42-inch ceiling fan for rooms 144-225 square feet, and a 52-inch ceiling fan for rooms 225-400 square feet. Measure your room and consider factors like ceiling height, airflow needs, and personal preference to choose the right size.
It's important to ensure the ceiling fan is properly installed and balanced for safety and optimal performance. If you're not comfortable doing the installation yourself, it's best to hire a licensed electrician to handle it.