Daewoo FR-4501W not cool enough

[Eaque]

Hello refrigeration engineers!

My main fridge is having issues (not cold enough) and I'm trying to troubleshoot the problem. It's a Daewoo FR-4501W (http://www.daewooelectronics.com.au/productdetail.asp?brand=D&category=FRIDGES&productcode=FR-4501W). The fridge is about 3 years old, and I haven't had any issue previously.
I have been doing some online research on that issue, and I've tried a lot of tips and tricks to fix it.

Here is a gallery of pictures I took of the various parts of my fridge: http://postimage.org/gallery/a9zz6z5m/

Symptoms:
While running completely empty, the freezer is cold enough to make icecubes fast, but the fridge part doesn't go below 6.5 degrees Celsius (with the dial set to 7 which is the max. and all the air vent going from freezer to fridge are open at the maximum)

What I have tried:
- defrosting the fridge. I've left the fridge with doors open for 3days, making sure that no ice could be left.
- opened the back bottom panel to access the compressor and coils. It was a bit dusty in there, but I've cleaned all of it, even the evaporation fan is clean as new.
- unscrewed the back panel in the freezer chamber. The fan is definitely working. While holding the door pressure knobs, the fan is definitely spinning at a decent speed.
- there isn't any food in the air vent, it's all very clean in there (see photos)

What I've noticed:
- the sides of the fridge, at the level of the freezer floor are getting quite hot (not sure if it's happening all the time though)
- there is definitely cold air coming out of the air vent in the fridge part, but not enough I guess
- When I close the freezer door and fridge door, I can hear the freezer fan spinning in there

Today, I also noticed that the insulation at the bottom part of the freezer back panel (made of styrofoam) is charred a little bit (http://postimage.org/image/kbfsuqkgp/). The flat base of that panel isn't flat anymore (http://postimage.org/image/67jxmcd95/).

Given all these details, do you see any explanation for the issue?
Is it a problem of air flow loosing efficiency because of that burned panel? If so, should I replace? was it burned by a bad auto defrost?

Thank you very much, I appreciate any help!

/Eaque

[frank]

Hi Eaque and welcome to the forum

Unfortunately, as engineers, we only deal in the science, so comments about fans spinning only give us part of the picture.

You do not tell us how old the fridge is ( so we can take into account the amount of work the compressor has had to do), what refrigerant it is charged with, or any operating measurements, i.e. running current, refrigerant pressures, system temperatures etc.

On a professional forum such as this, we need such information to be able to make an informed decision, otherwise, it is down to a best guess.

Sorry to be negative, but we need more information to be able to help you. Then, you may eventually need a local engineer to correct the problem, as fridge systems, on the whole, are not suited to DIY solutions.

Have you contacted a local engineer?

[marlon]

"The fridge is about 3 years old, and I haven't had any issue previously."

[mikeref]

Picture no.4, reading left to right. That fan has to be moving air when fridge is in cooling mode.