Freezer door won't close tightly and frost builds up

If it is a frost free freezer check that the door is closing properly and the seals are in good contact when the door is shut. Sometimes, when a door is not shut properly ice will build up, even in a no frost freezer

First you must fully defrost your freezer. Frost simply attracts more frost. A build up of frost large enough to prevent the door closing properly will grow very rapidly indeed and waste a lot of electricity; it will also overload the compressor and can cause it to fail prematurely.

If the seal is damaged then it will allow moist air in and cause frost. If the seal has simply become unseated, then refitting it will prevent a recurrence.

Unless you have a frost-free model, then all freezers eventually need defrosting. You can slow the process by never opening the freezer door unnecessarily and also by never leaving it open any longer than necessary. Frost free models rely on air circulation via a fan to prevent frost build up. If the fan fails, or if the freezer is overloaded and so preventing air circulation then it will still frost up.

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1)The door gasket on the freezer door helps keep the cold air in and the warm air out. If the gasket is dirty or damaged, it may prevent the door from closing properly, which can lead to frost buildup on your freezer walls. To make sure the door is sealing, slip a dollar bill or a sheet of paper between the gasket and the freezer and then close the door. If the bill or paper pulls free with little or no resistance, the gasket isn't sealing properly. Wipe the gasket with a damp cloth to remove dirt, grease and other residue. If the gasket is damaged, replace it with a new one. Sometimes frost can accumulate on the back panel of your freezer if the door is open too long or too often. When you open the door, you let warm, humid air inside, and this condenses and freezes. Make sure there are no packages preventing the door from fully closing, and limit how often you open the door by removing what you need all at once.
2)Ventilation is important because it ensures your freezer stays cold. If something inside the freezer blocks the internal vents, the freezer may become warm, causing condensation to form on the walls, and eventually leading to frost buildup. When loading your freezer, make sure there are no items resting against the rear wall of the freezer and space the contents out as much as possible to improve ventilation.
3)Side-by-side refrigerators with a built-in ice maker may accumulate frost if the flap on the ice dispenser doesn't close properly. This allows warm air to enter the freezer side, condense and freeze, causing frost buildup over time. Open the freezer door and examine the flap inside the ice chute. It should be flush against the housing. If it is not, empty the ice bin and make sure there is no ice or debris preventing the flap from closing.
4)If your freezer door closes properly and nothing is keeping it open, frost buildup on the back panel may indicate a problem with the freezer's self-defrost system. The self-defrost system turns off the compressor for a short time every six to 12 hours so it can turn on the defrost heater. This melts any frost buildup on the freezer coils, and the water drains to the pan beneath the freezer. If this component fails, frost continues to build. Move the contents to another freezer and turn your freezer off for 24 to 48 hours to manually defrost the interior. If frost builds up again, contact a qualified appliance repair technician to inspect the defrost timer and repair the problem.

you have a bad seal, Take a dollar bill and slide it in between the door seal and the frig. slide it up and down to see if if has drag on it. If you find places it dont touch loosen the screws and adjust the hinges till it fits tight. In some cases you might have to tweak the doors if they need it.

The gasket is not sealing correctly and is allowing warm air to meet cold air just below the seal.

Get someone with more skill to fit a new gasket , preferably one made by the original manufacturer , which should fit unlike some of the parts made by third party suppliers

In my case with constant snow and frost build-up in my bottom drawer GE freezer, it was because the drawer never properly closed. As one user noted, "there is no adjustment." However, there are "catches" at the rear of the drawer glides and in my case one needed adjustment because it was preventing the drawer from remaining closed tightly. SEE PHOTOS. The photos show many items removed, but to make this repair, you only need a butter knife to pop out the black plastic catch mechanisms at the back end of the drawer glides, and only if you can see that the spring is not properly positioned. SEE PHOTOS

There are several reasons this can be happening...

1. The seal on the door may have a tear or may not be seating properly...this allows excess warm air into the freezer compartment and in its effort to remove the same ...frost appears.

2. There is something call a thermistor that is cycled on and off as needed to remove excess frost accumulation and or ice buildup on the evaporator (freezer) coils...it is a heat strip which actually defrost the frost/ice. if this is not working frost will accumulate and eventually it will become Ice......now the remarkable thing about Ice accumulation is that you would think everything would remain cold or get colder ..however in this case the opposite occurs...it insulates the coils and thereby increasing the temperature...put a thermometer...one that is calibrated properly...(calibration can be set by placing a thermometer into a glass of ice water...the temp of a glass of ice water..after a few minutes setting will be exactly 32 degrees)..if the temperature of your refrigerator is gradually rising over the period of a week...you will need to call a tech or replace the thermistor and or trouble shoot other problems that can occur such as..

3. The evaporator fan may be going out although they usually make a high pitched whining noise of a whirring noise before they go out...not always and if they are intermittently cycling off then frost would build up...do you always here a fan running when you open the freezer...if so that is good...fan is working...but it may be cycling off at times when no one is aware.
P.S. the odds of your ice maker causing this are very, very slim...in 35 years in the industry ..I have never had an ice maker cause frost due to water spray...it will almost always result solid sheets of Ice..if it evers does cause a spray....which like I said is rare...lottery ticket type rare :-)

This should lead you in the right direction...if you need help in finding a reputable service company in your area let us know..I hope this has been helpful..if so PLEASE rate me....thank you... .......The Fang

look on the back wall of the freezer is there snow? if so you have a defrost component out (timer, limit, or heater) the fresh food compartment gets cool air from the freezer so check for blocked air pathways the build up of frost in the freezer stops air flow so you will be cold on freezer side and warm on ref side

Be sure the door seal is secure and closing tightly to prevent excessive moisture infiltration.