There is freezer burn on chicken in plastic packages

Unplug the drain tube by shooting hot water down it with a turkey baster. It is located underneath the evaporator.

Sounds like air infiltration gasket issue or power outage? proper freezer bags will stop the burning.

There is a drain the back of the freezer that is frozen. Your trickle of water comes from the ice that melts off of the refrigeration coils during the defrost cycle. You need to turn off the freezer, then remove the rear cover from the back wall to expose the coils. With a hair dryer, melt all of the ice. You will find a drain under the coils. Melts all of the ice in this drain so water can get out of the freezer. When this drain is clear, you can put everything back together, and your freezer should work normally.

use a vacuum food seal bag system.works for me...

No you cannot turn off the auto-defrost as the unit would stop working at all after a short time, and there's no provision to do so anyway. And I don't understand why you would thing the feature would have anything to do with fFreezer Burn. Freezer Burn imay be somewhat affected by the temperature, but mostly how well the food is sealed, keeping air out of the package. If freezing packaged meats from your supermarket for instance, the air in the package will burn them in, yes as little as two weeks. If that is the problem, you must repackage those items, eliminating as much air contact with the food in the package as possible to avoid the problem. I myself use both plastic wrap and aluminum foil to repackage anything I want to keep a while.

Either the drain hose is plugged up with ice and not dripping into evaporator tray, or the defrost unit needs to be replaced.

I have the same model + problem. You should not need to defrost this model manually if it's working correctly, but the ice build up you describe is probably due to a blocked pipe in the auto-defrost system at the back. You need to defrost properly to prevent recurrence.

Behind the upper freezer drawer there's an aluminium tray behind a plastic grille. Every few days this tray warms up to melt any accumulated ice behind this plastic grille (full height of the freezer). A pipe should take the meltwater down to a plastic tray below (pipe + plastic tray are visible if you take the lower panel off the back). Your problem is too much ice blocking that pipe: the heater can't cope and it doesn't melt, so the ice 'cascades' down the back behind the bottom drawer.

When you manually defrost, you must ensure that this pipe is clear, otherwise the auto-defrost won't work, and you may have to defrost manually again within days.

I have found that the best way to defrost the pipe is to remove the lower back panel, disconnect the corrugated flexible plastic pipe from the stub that comes from the bottom of the freezer, + pump steam into the stub (gently) using a hand-held steamer (with tube + nozzle). You don't have to empty the freezer or move your food as the door stays closed, and no steam gets into the freezer until the pipe is unblocked. Be sure to unplug the freezer before taking the back off! [There is a fan in this area that could start up without warning]

Check how much of the pipe is blocked by gentle probing with a pencil: the aluminium tray is about 105mm above the bottom of the stub. This measurement is important…

When the pipe is clear, there may still be too much ice in the aluminium tray above (not sure how much is 'too much') if you only created a narrow 'chimney' though the block of ice (likely to get blocked again). You need to widen that chimney by melting more of the ice in the aluminium tray. I use a simple steam nozzle made from an old-fashioned Bic pen with a couple of 1mm holes drilled just below the coloured bung at the end. This directs steam onto the walls of the 'chimney' rather than upwards.

There's no point steaming the walls of the plastic 'stub' pipe, so only use the home-made nozzle when your probe reaches 105mm (i.e. when you have melted all the ice in the plastic stub tube but before your 'chimney' has broken through the block of ice in the aluminium tray). If you judge this right, you'll melt almost all of the ice under a still-frozen top surface: no steam will get into the freezer and your food will stay frozen. With a probe it will be clear when you've broken through the top surface of the ice. When you have done so, it's time to look inside the freezer to see how well you have cleared the aluminium tray.

It's perfectly feasible to get all this done in 30 minutes.

Don't forget to replace the corrugated plastic pipe + valve at the bottom. It stops humid air from going into the freezer and icing up in exactly the area we've just been defrosting.

Take a lot of care with steam jets as they can burn you badly. You should check a first aid website so you know what to do BEFORE it happens.

Some of these tips may be helpful: (1) run the freezer at -18 degrees (the 'warmest' setting) so it's not working so hard. (2) Leave a big gap (>100mm) between the back of the freezer and the wall. (3) Clean the matrix of delicate tubes to the left of the fan whilst you have the back off [a small bottle brush is ideal; remove the fan for better access]. (4) Put something between the middle of the freezer and the wall to prevent the warm air that's being blown out behind the fridge from being sucked into the air intake behind the freezer (there is a baffle built in underneath, but nothing behind. (5) Mount the fan on spacers (with longer screws) so that it's closer to the heat exchanger… this means that a larger area of grille can act as an air intake. (6) Raise the unit off the floor a little to free up the air intake path beneath the freezer.

This is the moisture coming out of the food. It is what causes freezer burn.

The problem is made worse in frost free models by the defrost cylce. Best way to slow it down is to use vacuum bags or freezer bags. Also above 0 F food deterioates faster and below it gets freezer burn and the moisture problem faster.

There is normally a small filiament of metal which is attached to the defrost element and conducts heat down the drainpipe preventing ice build up. You can pour some boiling water onto this area and even wriggle a piece of plastic tubing down the drain pipe to dislodge any blockage. For future prevention, you can attach a piece of copper wire around the defrost element (in the absence of the original filiament) and extend it down the drainpiple

if you can't find a replacement, use a piece of flat vinyl siding that goes on houses. You can heat it and bend it as needed, or cut it and screw the pieces to a balsa wood frame for lightweight support. Glue or epoxy probably won't work as the cold temps make them brittle but external caulking may be ok to hold the pieces together. Be sure to sand all edges and corners as the cut plastic can be sharp. If you can disassemble the unit and place the door face down, you can fill the cavity with insulating foam to help stabilize it.