Help with Coke Machine

[DaveW92]

Hi,

I bought a refurbished Dixie Narco Coke machine (it is only 3-4 years old) about 2 weeks ago. After setting it up it worked fine for about a week and then all it started freezing the sodas. The thermostat was set at a "4" so I turned it all the way down to zero to warm it up.

I checked it the next day and it was warm (60-70 degrees). I turned it back up to a "1" setting and again it made the sodas very cold, almost freezing. I turned it down a quarter (to about a 3/4 setting...bewteen at 1/2 and a "1") and again it basically turned off (80 degrees).

I bought a new thrermostat and changed it out and set the new thermostat on about a "3". I checked it several hours later and again everything was real cold. I put a small (cheap) digital thermometer inside the machine and it read a 33 degree reading. I'm totally freaked out that things are going to freeze again. I turned the thermostat setting down to about a "2".

What is the problem? It has a brand new compressor that was just installed.

Any help?

THanks

[DaveW92]

I guess what my question is, what other component could be/is failing? I replaced the thermostat and the compressor is new.

Is there too much ***** (or similar fluid) in it?

I cant figure it out and it has me perplexed.

Thanks again,
Dave

[momo]

Please describe machine: does it have an ice accumulator (beer chiller type) or is it an under service counter machine (fridge that cools bottles of drinks with top slide door access)?

You could have problems with the hysteris (cut-in/cut out) settings on the thermostat.
On drinks machines and fruit juice/slush tanks it is sometimes not easy to get this adjustment right: you are not dealing with just one temperature.

[fireandice]

Could you tell us where the t/stat is sensing the temperature from, is it in the evap, after the evap or the cabinet temp. Thanks

[DaveW92]

Its a Coke vending machine. Its has a large door like a refrigerator and dispenses canned soda through a hole near the bottom on the door.

The thermostat is mounted inside the machine and has a long metal tube that sticks out the back of the thermostat. I was told that is what measures the temperature.

DAve

[The MG Pony]

Chances are a leak, as when they leak they go really cold. I'd get some one to pull the charge and weigh it and compar to the name plate.

[fri11j]

you need to make sure you have the correct thermostat for these machines...
ive found that if you can control the space temp of the cabinet by using a thermostat that you can only adjust the cutout temp and the thermostat probe monitors coil temp and not space/ambient temp.. if you can control the TD the you are not going to freeze your cans.. similar to a cyclic defrost fridge!!
i generally use a saginomiya dtbx193 which has an adjustable cutout between -3c and -10c and a fixed cut in at +5c and stick the thermostat probe into the coil!!

if im desperate I will use a danfoss #8 thermostat

[ckone180]

Just because I am a nice guy I will help you. You really should call a professional for this issue, but, disregard the leak thing, that is silly and should not have been posted. Install a Ranco A12-1506 thermostat in the same manner as the original, except, put the 'pigtail' into the coil of the evaporator. Depending on the thermostat stlye, you may have a coil sensing or an air sensing, and since I am not there looking at it, this will be the fix. Diet sodas freeze at a lower temperature than the regular soda, so keep that in mind. The thermostat I listed has a constant cut-in at 39 degrees, set it in the middle, somewhere between 4-5 and let it be. Good luck. And it has nothing to do with the accumulator or overcharging, these are critically charged systems that will not operate very long being low or high of refrigerant charge.

[ckone180]

Did you fix it?

[The MG Pony]

Just because I am a nice guy I will help you. You really should call a professional for this issue, but, disregard the leak thing, that is silly and should not have been posted. Install a Ranco A12-1506 thermostat in the same manner as the original, except, put the 'pigtail' into the coil of the evaporator. Depending on the thermostat stlye, you may have a coil sensing or an air sensing, and since I am not there looking at it, this will be the fix. Diet sodas freeze at a lower temperature than the regular soda, so keep that in mind. The thermostat I listed has a constant cut-in at 39 degrees, set it in the middle, somewhere between 4-5 and let it be. Good luck. And it has nothing to do with the accumulator or overcharging, these are critically charged systems that will not operate very long being low or high of refrigerant charge.

Well some one has a rather inflated sense of self.

Lets see, ran fine for 2 weeks, So the thermo was doing well other wise it would not have run well. As critical charge systems loose charge they go into deeper suction as load handling drops off, very cold evap, tends to freeze stuff in the box. He stated changes the therm setting to no resolve.

Silly? No just cautious, check every thing sequentially.

Silly is posting "Just because I am a nice guy I will help you." all so comes of a smudge arrogant in my books too, why ells would one have to say such a thing other then to stroke their ego?

[taz24]

Well some one has a rather inflated sense of self.


Silly is posting "Just because I am a nice guy I will help you." all so comes of a smudge arrogant in my books too, why ells would one have to say such a thing other then to stroke their ego?

I think you are taking it too personaly.
I read the post and thought it was a bit tongue in cheek
I agree with his short of gas senario.
Low gas could cause the evap to ice up but not very offten does it cause the temp to drop too low, simply because if it was gas then the stat would still opperate and cut the system out. It would not achieve the correct temp

Just my opinion

taz

[The MG Pony]

I think you are taking it too personaly.
I read the post and thought it was a bit tongue in cheek
I agree with his short of gas senario.
Low gas could cause the evap to ice up but not very offten does it cause the temp to drop too low, simply because if it was gas then the stat would still opperate and cut the system out. It would not achieve the correct temp

Just my opinion

taz

Well at least you explained why!

A personal pet peeve is the type who dismiss some thing flat off with out explaining it, to me it says they do not understand why it is wrong and thus unqualified to say "Its silly". If one is to say another's suggestion is wrong or silly they sure as hell better be telling why it is rather then snub their noses high in the air and climb on top of a soap box!

[davecool]

im curious about this and the replies that have been given. personally i dont think the thermostat is the problem here, you say a new compressor has been fitted recently i take it that this was fitted before your temp problems and a thought just came to me, have you checked that the comp has been wired correctly, if it hasnt then no amount of adjustment or replacement of thermostats will help as it may be wired to run continuous. just a thought as i said.

[ckone180]

Well at least you explained why!

A personal pet peeve is the type who dismiss some thing flat off with out explaining it, to me it says they do not understand why it is wrong and thus unqualified to say "Its silly". If one is to say another's suggestion is wrong or silly they sure as hell better be telling why it is rather then snub their noses high in the air and climb on top of a soap box!

Personally, who cares about your pet peeves? It was intended to be tongue in cheek, but you decided to start boosting the issue. If you had any slight ability in this field, you would have not even came close to posting the 'low gas' cause. That is "silly." If a unit is thermostatically controlled, and the thermostat is operating appropriately, then 'low gas' would do nothing to freeze the product. Therefore, "silly" would be accurate.

The fact is, I am qualified and was looking to help this guy, sort of by breaking the ice. If you have no real addition to this post, stop slowing progress. If you have input that can come closer to being an actual resolution, be my guest. Post away. As far as I have seen, you may want to change fields.....JMO.

[ckone180]

im curious about this and the replies that have been given. personally i dont think the thermostat is the problem here, you say a new compressor has been fitted recently i take it that this was fitted before your temp problems and a thought just came to me, have you checked that the comp has been wired correctly, if it hasnt then no amount of adjustment or replacement of thermostats will help as it may be wired to run continuous. just a thought as i said.

Good idea, but I think it should have froze the drinks quicker than two weeks under this scenario. I do think it is a thermostat issue, but it may be an application of the thermostat rather than a failed thermostat.

[taz24]

Good idea, but I think it should have froze the drinks quicker than two weeks under this scenario. I do think it is a thermostat issue, but it may be an application of the thermostat rather than a failed thermostat.

As with all jobs to be totaly sure of your responce you would need to be stood in front of the case while makeing your deceision as to the fault.
We can only go on what we are told and then offer the best solution we think.

Personaly I think its a control issue, either the wrong stat has been fitted or it has been fitted in the wrong position or it is the wrong stat fitted in the wrong position.
Short of coming to site and watching it run for an hour or so I can't tell

Cheers taz.

[The MG Pony]

Personally, who cares about your pet peeves? It was intended to be tongue in cheek, but you decided to start boosting the issue. If you had any slight ability in this field, you would have not even came close to posting the 'low gas' cause. That is "silly." If a unit is thermostatically controlled, and the thermostat is operating appropriately, then 'low gas' would do nothing to freeze the product. Therefore, "silly" would be accurate.

The fact is, I am qualified and was looking to help this guy, sort of by breaking the ice. If you have no real addition to this post, stop slowing progress. If you have input that can come closer to being an actual resolution, be my guest. Post away. As far as I have seen, you may want to change fields.....JMO.

So psychic and an ass gotcha.

[taz24]

So psychic and an ass gotcha.

Now Now boys!

Now I want you both to sit in opposit corners with your fingers on lips.

No ifs, no buts just do it.
When you can be good boys and stop Squabbling I'll let you come out and play again

All joking apart don't get too serious lads, there are more important things to worry about than a fridge stat.

taz

[monkey spanners]

In some systems (domestic fridges etc) being short of refrigerant can cause over cooling as the stat senses evaporator temperature and not air temperature.

Jon