Split it first: is the water inside the cabinet, or on the floor outside it? Water pooling inside — under the crisper drawers, or as a sheet of ice under the freezer floor — is almost always a blocked defrost drain. Water on the floor points instead at the drip pan, the ice maker supply line, or condensation from a failing door seal.
Inside or outside?
| Where the water is | What it points to |
|---|---|
| Under the crisper drawers | Blocked defrost drain — by far the most common |
| Sheet of ice under the freezer floor | Blocked defrost drain, frozen solid |
| Running down the inside back wall | Defrost water not reaching the drain hole |
| Puddle on the floor at the front | Drain overflowing forward, or a door seal issue |
| Puddle on the floor at the back | Cracked or overflowing drip pan, or a water line |
| Only since the ice maker was plumbed in | Water supply line or its connection |
| Droplets on the inside walls | Condensation — door seal, or the door left ajar |
The blocked defrost drain
Every frost-free refrigerator runs a defrost cycle several times a day: a small heater warms the evaporator coil, the frost melts, and the meltwater runs down a channel, through a drain hole at the base of the freezer compartment, along a tube, and into a shallow pan sitting on top of the compressor. The heat of the compressor evaporates it.
That drain hole is narrow and it clogs — with food debris, with ice, or with a slimy biofilm that builds up over years. When it does, the meltwater has nowhere to go. It backs up and finds its way into the fridge compartment, where it collects under the crisper drawers, or it freezes into the sheet of ice people find under the freezer floor.
Water that appears in the fridge every day or two, with no ice maker fitted and no visible plumbing, is a blocked defrost drain until proven otherwise. It is also one of the cheapest repairs on the appliance — usually nothing but your time.
Clearing the drain
Unplug the refrigerator before working inside it. Take the food out, and have towels ready — there is usually more trapped water than you expect once the blockage moves.
- Find the drain hole
It is at the base of the freezer compartment, usually at the back, often behind the rear panel. In some models it sits under a small cover or at the bottom of a moulded channel. Empty the freezer and look for a small hole at the lowest point of the coil area.
- Thaw any ice around it
If the hole is iced over, do not chip at it. Warm it gently — a cloth soaked in hot water held against the ice, repeated a few times, works well. If the whole area is heavily iced, unplug the fridge and leave both doors open for 24 hours with towels down.
- Flush the drain
Pour warm (not boiling) water into the hole from a jug or a turkey baster. It should run away freely. If it backs up, the tube below is still blocked.
- Clear the tube
Feed a pipe cleaner, a length of stiff plastic tubing or a plumber’s drain brush gently down the hole to break up the blockage, then flush again with warm water. Avoid anything sharp or metal that could puncture the tube.
- Check the drip pan
Slide the fridge out and look underneath for the shallow pan above the compressor. Empty it, wash it, and check it is not cracked or dislodged. A pan knocked out of position during a previous move will drip onto the floor every defrost cycle.
- Level the appliance
Most refrigerators are designed to sit very slightly higher at the front so doors self-close and internal drainage runs the right way. Check with a spirit level and adjust the feet if the machine tips backwards or sideways.
Other causes
- Ice maker or water dispenser line. If the leak started after plumbing work, or you have a water dispenser, check the supply line and its connections at the back. Look for a slow drip at the compression fitting — these weep long before they fail properly.
- Door seal. A seal that no longer grips lets warm humid room air into a cold cabinet, and the moisture condenses out onto the walls and shelves. Test with the paper trick: close the door on a sheet of paper and see whether it pulls out freely.
- Door left ajar. An overfull shelf or a bottle stopping the door closing fully produces exactly the same condensation, and people rarely notice the door is not shut.
- Cracked drip pan. Common on older appliances or after a house move, and easy to miss because it is out of sight underneath.
When to call a professional
Call an engineer if the drain will not clear, if water is coming from the sealed refrigerant tubing rather than the drain path, or if you find a leak in the plumbed water supply that you are not confident isolating. Also call if the leak is accompanied by a total loss of cooling — the two together can indicate a more serious failure, and our not cooling guide covers what to check.
Stop and call a qualified appliance technician or electrician if you find scorched or melted wiring, smell burning, see water that has reached electrical components, or if the fault returns immediately after a repair. Never bypass a safety device — thermal fuses, door interlocks and flood switches fail for a reason, and defeating one converts a broken appliance into a fire or flood risk.
