7 replies to this topic

[jschildm]

I am brand new to this forum and am just an individual with a vending machine in his barn. I was able to pick-up a Dixie Narco 348 for a donation to the church (they wanted to get it out of the way). I knew nothing about vending machines going into it, but have been able to figure out a decent amount just by tinkering with it. In general, most of the stuff works on the unit. I plugged it in, coin and dollar functions worked, cans got cold, etc. 7 of the 10 vending locations work as they should (I believe the motors are bad on 2 of the three, and I discovered the gearbox is bad on the 3rd (I think I can combine the good motor with a gearbox to get another one working though). That is a little background information, so no on to my potential problem.

 

After having it on a bit, the cans in the vending machine were cold, but the cooling unit ran all the time. After doing a little research, I found out the evaporator fan is supposed to run all the time, and the other portion is controlled by the thermostat. When I turn the thermostat knob to off, the evaporator fan stays running (as I believe it is supposed to do), and the rest shuts off. Originally when I turned it back to any of the numbers, it would instantly turn back on and run. The evaporator tends to frost on the first tube, getting smaller as it goes from the elbow to the other side. I have some pictures, I believe, that I can upload.

 

When I have messed with it recently, I can turn the thermostat knob to off and it shuts off, and then if I turn it immediately back on, it won't turn the cooling portion on right away. It will kick on when it gets warm enough for the thermostat to do so. I have not heard it shut itself back off at all though. Based on this behavior I am wondering if the thermostat isn't functioning properly and shutting it off? The other potential issue would be freon levels.

 

Sorry for the long winded description, and thanks ahead of time for the help.

 

John

[AZVendor]

If you leave the machine on for a few hours, with a thermometer inside it, does it get down to 40-45 degrees.  If so and the evaporator isn't frosting over or getting icy then your machine is working fine.  If, after a few hours, the temperature is higher than 45 deg and you have signs of ice on the fins of the evaporator you then have low freon.  Turning the compressor off with the thermostat and then turning it right back on will often times cause the compressor to only click on and back off because the gas pressures are too high in the compressor.  In that scenario the condenser fan will still be running because the thermostat is passing power to the cooling unit whether the compressor is on or not.  As long as the compressor turns off when the thermostat is off and the cans don't freeze solid when the thermostat is at the proper setting of 3 1/2 then your thermostat is working fine. 

[jschildm]

I have been meaning to get a thermostat in there, but I haven't done it yet. I will do that here in the next few days and get back to you. I didn't know there was a correct setting, but I have been keeping it on three, so I'll make that small adjustment and we'll go from there.

 

On another note, I think I have seen you say you have parts for sale before AZVendor. Do you have some of the vend motors for sale?

[AZVendor]

Yes I do.  The motors are $36 each.  You can PM me for information. 

[jschildm]

I put a thermometer in the vending machine and set it on 3.5 and is reading 30 degrees. I am getting some ice build up on the evaporator though.

[jschildm]

https://dl.dropboxus...2_182747948.jpg

[AZVendor]

That ice is evidence of low freon.  You'll need a qualified refrigeration tech to recharge it for you.  If you leave it you will eventually have a frozen evaporator.

[jschildm]

Thats what I assumed. Thanks for helping with some diagnostics to confirm though.