Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to clean a central air conditioner [title] Shut off power to the unit. [step] There should be an outdoor shutoff near the condenser unit. This will resemble a square box on the wall of the apartment or house.

Ending1: Turn on your washer and dryer and then unplug it from the power line. [substeps] Loosen the hose valve that needs removal, then and you will be able to remove the cold air leaving the unit. Ending2: Inside, look for a switch that you can slide to the " off " position. If there is no switch, you'll need to manually pull the plug which feeds power to the condenser. Ending3: [substeps] If the mercury turns from the normal color to a bright yellow, perform an electricity shutoff. This will diffuse electricity safely through the unit's sodium-supply tanks and light fixtures. Ending4: Shut off power to that unit for about 15 minutes. [substeps] If your power outlet is not nearby, this can cause block electrical lights and environmental problems.

Answer format: ending1/ending2/ending3/ending4