[rgnlkngtylrbmbstk]

I have a fairly big kitchen fridge/freezer given to me years ago, so I'm guessing circa late 90's or early 00's.
I cut the divider between top and bottom, and gutted the plastic housings. It's worked great for about a year and a half, holding 11 kegs (9 taps) and running ~40° with a 2° swing, garage temps. Lately the it's running at about 52-56 and the inlet of the condenser coils has been building a blob of ice that won't go away on its own. In a normal setting this would indicate a problem for a professional, but I'm wondering if it's simply that I've taken the back of the freezer off, and now the "heat rises" function of the defrost won't get to the part that is freezing up.
Anybody know fridges and can help me diagnose? I know things happen, and as old as it is it may just be time to let 'er go, but I'd rather fix it!

[tschmidlin]

Try unplugging it for a couple of days and letting the ice melt, then plug it back in.  See what happens.

[stlaleman]

Make sure the coils are clean and air can flow freely around them.

[rgnlkngtylrbmbstk]

Thanks guys. I've unplugged it a number of times. Condensing coils are clear, but that back panel that should be in front of it (back of the normal freezer wall) has been removed, and I'm wondering if the fan blowing straight out into the whole fridge chamber rather than being forced across the coils are making the ice build up. It only happens right at the inlet of the coolant, possibly blocking further freon flow? Also the defrost heater is on the bottom of the coils, thinking the lack of forced air flow is keeping it from doing much to the coils themselves, certainly nothing all the way in the top right where the buildup is.
I was considering replacing the defrost thermostat, but maybe I just need to get a piece of FRP or something stuck up against it similar to how it was designed, see if that fixes it.