What tool can I use to unblock my refrigerator drain hole?

Unblocking a frozen or obstructed residential refrigerator defrost drain hole can be accomplished easily using common household tools designed to clear ice and debris without damaging delicate plastic lines. The most effective tools include a turkey baster or squeeze bottle filled with warm water to melt stubborn ice plugs, a flexible nylon pipe cleaner or a small bottle brush to scrub away algae slime, and a length of stiff, blunt copper or plastic wire to gently push through the drain tube. Never use sharp metal screwdrivers or rigid knives to chip away ice inside the drain trough, as puncturing the thin plastic liner or refrigeration tubing will cause permanent, catastrophic damage. You can troubleshoot drainage flow easily. You can verify that your unblocking procedure is successful when pouring warm water results in unhindered flow into the lower drip pan.