Vendo model 110 icing up in one are only

[Arch Stanton]

My Vendo 110 is icing up in one spot only. The picture below is without the ice but it is getting iced up on the small horizontal enlarged tube I am assuming that is the cap tube it has the small wire coming out of the rear of it.
Any suggestions the unit is gauging a charge and still gets cold but the temp gets too warm then runs the temp back down low I didn't want to start messing with the cut in and out until I find out a little bit more of what may be wrong
The tube gets about 1" of ice on it nowhere else and the fan is running as it should and no leaks from outside air entering the box

Thanks Joe

[johnieG]

without putting a set of pressure gauges onto your system you can only guess at whats going on.  but that also depends on whether or not your system has a service port available to tap into the lines.

but if it's only Icing towards the capillary end of the evaporators expansion bulb then chances are your system either has a low charge/leak or possible water infiltration into the freon causing the cap' tube to block up with ice crystals, I suspect the latter, ( ice crystals in the capillary tube) because it get warm, then after a bit it goes back to cooling only to repeat the warm-cold-warm trouble. one clue would be a sudden spike in the low-side pressure with a corresponding drop in the high side, this will also drive up the compressors case temperature .

solution A:   Recover the freon, nitrogen pressure check the system & fix the leak and install a filter/dryer, deep vacuum & recharge the system.
solution B:   Added a moister absorbing additive along with refrigeration system leak-stop & recharge the system & hope for the best.

[Arch Stanton]

I shut the machine down for a few hours yesterday and started it back up it has been fine so far running as it should maybe it was ice crystals I am assuming it will happen again