9 replies to this topic

[Ruskie]

I checked one of my soda machines and the evaporator was completely frozen from top to bottom and side to side.
What can the problem be.
This is a Vendo cooling deck. Yes both circulation fans are running.
Thank

[Vendtech]

This depends, as always you should not store items under the drop chute which will block the circulation around the evaporator. Given that, low freon could be a problem. If this is the case usually the evaporator will ice up from the top and in the beginning can ice the entire thing up. After awhile the freon will be so low the icing will only be at the top. Air leak around the door gasket, esp. if you live in hummid climate. Warm, moist air condensates on evap. and will freeze and build up over time. Just had a Vendo freezing up and one of my men found the drain spout leading to the drain pan was broken off. The holewas large enough that the warm air was being sucked right in. If you have a manual cold control this could be set too low or might be faulty. Are you sure the evap fans are working or are you going on sound. If you didn't see the blades running, the blades could be broken off and you could be hearing a bladeless fan motor. This will for sure freeze up.

[Ruskie]

Thanks for the reply, I did pull the drop chute to check the fans. How can low freon cause icing? I do have a manual temp controller. If its bad it will either not start the compressor or not turn it off at the set temperature. So if the compressor continually runs without defrosting, frost will accumulate until the whole unit is a solid block of ice. Could this be the case?

I understand that a compressor allowed to run continuously would freeze the cans or bottles, this is not the case here? Or both can occur?
Thanks for your input.

[Steve Fischer]

When this happens, my first assumption is usually that the door didn't get closed all the way and there was an air leak. I usually turn off the compressor to let the coils thaw, put it back into service, and keep my fingers crossed.

With regard to low freon, there has been some difference of opinion on this forum on that subject. Some say it can't happen but having worked as a building engineer at a moderate sized nursing facility, I've seen air conditioners do this so I can see it being possible with smaller refrigeration. There's a fine line where you lose enough freon to keep the system from operating efficiently but still have enough to have some really cold spots. Since the system can't chill enough, it doesn't cycle properly and defrost. Since it doesn't defrost, the cold spots build ice, which causes the system to work even less efficiently. It eventually snow-balls, if you'll pardon the expression, until your evaporator coils look like a glacier.

[Vendtech]

I believe your correct Steve about the freon. Everytime we have an evaporator iceing up at the top, when we tap the line and check the freon level, it is low. I am not a refer guy, but over the past 22 years this is what I have seen over and over. Yes Ruskie, this can be the case with a manual cold control. I hope you find the problem with your unit. I know frozen systems can sometimes be a bear to figure out.

[vend1ng]

Thanks for the reply, I did pull the drop chute to check the fans. How can low freon cause icing? I do have a manual temp controller. If its bad it will either not start the compressor or not turn it off at the set temperature. So if the compressor continually runs without defrosting, frost will accumulate until the whole unit is a solid block of ice. Could this be the case?

I understand that a compressor allowed to run continuously would freeze the cans or bottles, this is not the case here? Or both can occur?
Thanks for your input.

Change the t-stat its bad..... There is NO WAY possible for a evap to freeze completely from top to bottom with low freon. If it could we wouldn't need freon!! Yes you can get some ice on a corner where the cap tube enters the evap coil but that is it ...... I am stunned that some one with a tag "Vendtech" would even say that. Its simple it takes freon to make it freeze and a frozen coil is to much freezing caused by running continually. Cans may or may not freeze if t-stat sticks. On most compressors now days they don't have enough BTUs to freeze cans you may get freezing on diet pop and depending on how many cans you have in the machine. Just my thoughts
Vend1ng

[Vendtech]

Far be it for me to say I am an expert, vend1ng...... oh wait I did indicate in my second post that I wasn't a refer tech. So pardon me vend1ng for "stunning" you so, I didnt realize you were so thinned skin and intollerant. Lets look at InspectAPedia @http://inspectapedia...ACCoilFrost.htm. Scroll down to item #9 under "What Are the Common Causes & Repairs for Ice or Frost Build-up on an Air Conditioning Cooling Coil" . Icying does start at the top and if caught early enoughthat is where it stops because it is taken care of then. My company has over 3000 machines in the field. This includes office coffee, snacks, cold food, drink machines, both box and glass fronts, coffee vend machines. Our drivers are good, but they fill machines and go to the next one and alot don't look under the chute. This allows the ice to build up over some time, eventually covering the evaporator. We have taken these units out and check freon levels and they have been low, we check for leaks and sometimes don't find the really small ones, we recharge and put back in the field and they are fine for a short time. Then they start to freeze up again. Check freon levels and yes they are low again. We finally find the leak and repair it, and what do you know, no more freeze ups. But of course that is only in my world. In Mr. Vend1ng's myopic world it doesn't work like that. As to the statement "On most compressors now days they don't have enough BTUs to freeze cans " another tale from the impossible : We had a National 431 cold food, less than 6 months old had a triac go bad, I know Vend1ng triacs never go bad in your world, but this one did. Driver checked the temp in the machine, it was down to -5 deg. Machine had frozen rock solid everything. I didn't think it could have done it when the driver called me, so I went to the machine and it was down to -8 when I arrived. Called National and they said it wasn't possible, Not enough BTUs to do it. Had to put my temp probe in machine and take a picture of the readout to send to Crane National. I guess Vend1ng was Mr. "I know everything" at National that day too. Never claimed to know everything, admit that I am not an expert, only relaying what I have seen in my work over the years. Hate seeing good site trolled by self important arrogant people. So please Vend1ng, please stayed "STUNNED" when someone says something that may go against what you believe. At one time people thought the earth was flat, and they too were "STUNNED" when sailors sailed around the earth. You make the shallow minded people of the world proud sir.

Here is another idiot that doesnt know what he is talking about: watch at about 1 min 55 sec. :. Don't you just wish God would strike these morons down so Vend1ng doesn't have to breath the same air..... Vend1ng..... Oh my God someone call 911 Vend1ng has gone into "OVERSTUNNED".

[vend1ng]

Far be it for me to say I am an expert, vend1ng...... oh wait I did indicate in my second post that I wasn't a refer tech. So pardon me vend1ng for "stunning" you so, I didnt realize you were so thinned skin and intollerant. Lets look at InspectAPedia @http://inspectapedia...ACCoilFrost.htm. Scroll down to item #9 under "What Are the Common Causes & Repairs for Ice or Frost Build-up on an Air Conditioning Cooling Coil" . Icying does start at the top and if caught early enoughthat is where it stops because it is taken care of then. My company has over 3000 machines in the field. This includes office coffee, snacks, cold food, drink machines, both box and glass fronts, coffee vend machines. Our drivers are good, but they fill machines and go to the next one and alot don't look under the chute. This allows the ice to build up over some time, eventually covering the evaporator. We have taken these units out and check freon levels and they have been low, we check for leaks and sometimes don't find the really small ones, we recharge and put back in the field and they are fine for a short time. Then they start to freeze up again. Check freon levels and yes they are low again. We finally find the leak and repair it, and what do you know, no more freeze ups. But of course that is only in my world. In Mr. Vend1ng's myopic world it doesn't work like that. As to the statement "On most compressors now days they don't have enough BTUs to freeze cans " another tale from the impossible : We had a National 431 cold food, less than 6 months old had a triac go bad, I know Vend1ng triacs never go bad in your world, but this one did. Driver checked the temp in the machine, it was down to -5 deg. Machine had frozen rock solid everything. I didn't think it could have done it when the driver called me, so I went to the machine and it was down to -8 when I arrived. Called National and they said it wasn't possible, Not enough BTUs to do it. Had to put my temp probe in machine and take a picture of the readout to send to Crane National. I guess Vend1ng was Mr. "I know everything" at National that day too. Never claimed to know everything, admit that I am not an expert, only relaying what I have seen in my work over the years. Hate seeing good site trolled by self important arrogant people. So please Vend1ng, please stayed "STUNNED" when someone says something that may go against what you believe. At one time people thought the earth was flat, and they too were "STUNNED" when sailors sailed around the earth. You make the shallow minded people of the world proud sir.

Here is another idiot that doesnt know what he is talking about: watch at about 1 min 55 sec. :http://www.youtube.c...feature=related. Don't you just wish God would strike these morons down so Vend1ng doesn't have to breath the same air..... Vend1ng..... Oh my God someone call 911 Vend1ng has gone into "OVERSTUNNED".

Then why did you give false advice on subject you didn't know anything about when you knew you weren't a refer tech? With a tag of "Vendtech". The guy isn't even a "vendtech" and he knows it takes freon to freeze. Part of the purpose of this board is to help protect vendors from false advice. You are welcome to believe how ever you want and if your company wants to pay you for doing everything twice because you don't know HOW things work thats their problem. But if they come here and ask I'll tell them the truth. As for nat'l 431 depending on which era of machine they came with 1/2 hp compressors and do have the BTUs to freeze. The best part about this is this vendor here gets to decide who is "overstunned"
Vend1ng

[vend1ng]

I believe your correct Steve about the freon. Everytime we have an evaporator iceing up at the top, when we tap the line and check the freon level, it is low. I am not a refer guy, but over the past 22 years this is what I have seen over and over. Yes Ruskie, this can be the case with a manual cold control. I hope you find the problem with your unit. I know frozen systems can sometimes be a bear to figure out.

Just curious if your not a refer tech how do check freon level? Since the only info on machines is in ounces do you pull it out and weigh it? How can frozen systems be a bear? Do they run on magic? Just wondering?
Vend1ng

[Steve Pixley]

Can you please get the model of the machine? It sounds like you could have a thermostat issue. If you suspect the thermostat, unplug it and put a continuity meter across the contacts and crank it again. The continuity should open and close coinciding with the clicks.