If you live in Fort Lauderdale, you have probably opened your freezer and found frost where it should not be. Frost on the back wall, ice building up around the door, or a freezer that slowly stops cooling because the coil inside has turned into a block of ice. This is one of the most common freezer problems in South Florida, and humidity is the main reason it happens here more than in drier parts of the country.
A freezer works by moving heat out of the box and keeping the inside cold and dry. The evaporator coil inside the freezer gets very cold, and air blows across it. When warm, humid air gets into the freezer, the moisture in that air freezes on the coldest surface it can find, which is the evaporator coil. A little frost is normal. The defrost system is built to deal with it. Every so often, a defrost heater warms the coil, the frost melts, and the water drains away. When that cycle works, you never notice it. When any part of it fails, frost builds up layer by layer until airflow stops and the freezer cannot cool properly.
The first place to look is the door. A freezer door has a rubber gasket that seals it shut. When the gasket is torn, flattened or dirty, warm humid air leaks in around the edge all day and all night. You can test it at home with a piece of paper. Close the door on the paper so half of it sticks out, then pull gently. If the paper slides out with almost no resistance, the seal is weak in that spot. Try it in several places around the door, because a gasket can fail on one side and hold on the other. Also check that nothing inside the freezer is stopping the door from closing fully. A box, a bag or a drawer that sticks out a little is enough to leave a gap, and in Fort Lauderdale humidity a small gap lets in a lot of moisture over a day.
The second cause is the defrost system itself. It has three main parts: a defrost heater, a defrost timer or control board, and a defrost thermostat. The heater melts the frost, the timer or control board decides when to run the heater, and the thermostat decides when the coil is warm enough to stop. If the heater has burned out, the frost never melts. If the timer is stuck, the heater never runs. If the thermostat has failed, the heater may run too long or not at all. Any one of these faults gives the same result from the outside: frost that keeps growing. A technician tests each part rather than guessing, because replacing the wrong part leaves the real fault in place.
The third cause is the way the freezer is used. Every time the door opens, humid air comes in. A door left open while food is put away, or a freezer packed so full that air cannot move around the coil, makes the problem worse. Food should not be packed tight against the back wall, and hot food should be left to cool before it goes in, because hot food gives off steam that freezes on the coil.
Garage freezers suffer more than kitchen freezers. A garage in Fort Lauderdale is hot and humid for most of the year, so the compressor runs longer and the condenser coil collects dust faster. If your garage freezer frosts up often, check the door gasket first, then check that the condenser coil is clean and has clear air around it.
There are a few things you can safely do at home. Check the door seal with the paper test. Make sure the door closes fully and nothing blocks it. Check that the temperature control has not been knocked to a warmer setting. Move food away from the back wall so air can move. Clean the condenser coil if you can reach it safely and the unit is unplugged, following the manual for your model. Never chip ice off the coil or the walls with a knife or a screwdriver. The coil and the refrigerant lines behind it are easy to puncture, and a puncture turns a defrost repair into a much bigger job.
If the frost comes back soon after you clear it, or the freezer is not cooling properly, the defrost system, the door gasket or the airflow needs a technician. A technician checks the gasket, tests the defrost heater, timer and thermostat, checks the evaporator fan, and confirms the temperature pulls down after the repair.
Frost is not just untidy. A frosted coil cannot move heat properly, so the compressor runs longer, uses more power, and wears out sooner. Food stored in a freezer that cannot hold temperature is at risk, and in a commercial freezer the stock is at risk too. In Fort Lauderdale, a freezer needs its door seal and its defrost system working properly to stay ahead of the moisture in the air.
If your freezer keeps frosting up, call [PHONE]. Tell us the freezer type, the brand if you know it, and where the frost is building up. We serve Fort Lauderdale, including Las Olas, Victoria Park, Coral Ridge, Wilton Manors, Oakland Park and Harbor Beach, and across Broward County.