AC cleaners remove the indoor unit, wash it and then reinstall it. My room's last AC developed a gas leak after the serviceman reinstalled it. It was only 2 years old AC. I sold it and bought a new one, since then I made a policy of not removing the AC until it dies. After six years, no complaints. Cleaned indoor unit myself, fins with toothbrush and blower with paint brush. Cleaned outdoor unit with pressure washer.