The short answer
Most water under a second fridge is defrost melt or condensation that has lost its path, not a plumbing fault. Look for ice on the freezer floor first: if it is there, the defrost drain is blocked and everything else follows from that.
What you actually see and hear
- Water inside at the bottom of the fridge section — A blocked defrost drain sending melt water forward instead of out.
- Ice sheeting on the freezer floor — The same blockage, freezing before it can drain.
- Water at the back on the floor — The evaporation pan, full, cracked or displaced.
- Water all around the base in humid weather — Condensation on a cold shell in an unheated room, not a leak.
- NEAR MISS - water only on the plumbed supply side — That is a supply fitting, and it is the one that can do real damage.
Causes, most likely first on this machine
- Blocked defrost drain — First on any frost-free cabinet. The drain is narrow and cold and it blocks with debris or an ice plug, and the water then goes wherever gravity takes it.
- Evaporation pan displaced, cracked or overfull — Second, and more likely on a second fridge because it has usually been moved several times.
- Condensation in an unheated humid room — Third. A cold cabinet in a damp garage sweats, and in bad weather that alone will wet a floor.
- Cabinet not level on an uneven slab — Fourth. A forward lean sends both melt water and condensate towards the front.
- Door seal worn with age — Fifth. It brings humid air in continuously, which both raises the condensation and loads the defrost system.
- Supply fitting on a plumbed cabinet — Last in likelihood, first in urgency: mains pressure behind a cabinet does not stay a small problem.
Check in this order, and why
- Look at the freezer floor for ice — It is the single most informative look on this page.
- Pull the cabinet out and check the evaporation pan — Expect it to be out of place if the fridge has been moved.
- Check the cabinet is level with a slight backward tilt — Cheap, and it stops the puddle returning.
- If the cabinet is plumbed, dry and check the fitting with a tissue — This is the only cause here that gets worse quickly.
What an owner can safely check
- Mop up and watch where water returns first — On a sloping floor, the puddle is not the source.
Tools: towels, spongeAbout 20 min
- Clear the defrost drain from the freezer side with warm water — A turkey baster or a soft tube - never a metal probe near the liner.
Tools: turkey baster, warm waterAbout 30 min
- Pull the cabinet out, empty the pan and reseat it square — Check for cracks while you have it out.
Tools: towel, shallow trayAbout 20 min
- Level the cabinet on the slab with a slight backward tilt — Shims under the front feet are usually all it needs.
Tools: spirit levelAbout 20 min
- Dry the supply fitting and re-check it after an hour — Only applies to plumbed cabinets, but it is the important one.
Tools: tissueAbout 15 min
- STOP HERE before removing the freezer rear panel to reach a frozen drain — The defrost heater and live terminals are behind it.
Before you open anything
Safety
Unplug the appliance or switch off its breaker before removing any panel - a capacitor can hold a charge after the power is off. A second fridge is often on an extension lead in a garage: switch off at the breaker rather than trusting a socket switch, and keep water away from the lead. Never chip frost off a cooling plate with anything metal - the tubing behind it is thin and a puncture ends the appliance.
When to call a technician
Call when the drain will not clear from inside the freezer, because the blockage is then behind the rear panel with the heater and the live terminals. Call promptly for any leak at a plumbed supply fitting. For everything else here - a displaced pan, a tilted cabinet, condensation in a damp room - the work is yours and it is straightforward, which is just as well on a cabinet where a call-out is a meaningful fraction of the replacement price.
Nearest pages of this class
What this page does not cover
This page is written for the overflow or second refrigerator class, not for one family or model line. Where a brand- or model-specific page exists for your unit it is the more specific answer and it is linked above, so go there first if your machine is named. What is deliberately not here: compressor and relay part numbers, thermostat calibration figures, refrigerant charge and shelf dimensions, all of which differ by family and belong on the page for that family.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
