Vendo 81b cooling question

[PC3239]

Hi, just registered here though have been reading for years.  I know this question has been asked in various forms before but couldn't find an answer specific enough to help me.

I have Vendo 81B roundtop machine.  It cools to a perfect 38 degrees, problem is the frequancy of the compressor coming on and off.  The compressor will run for about 1 minute, 30 seconds and then will shut off for about 4 minutes comes back on again repeating this cycle.

I have taken the cover off of the front of the thermostat and adjusted the Cut in and out switches but it only helps for one cycle.  For example I turned the bottom screw (don't know if it is the cut in or cut out) counter clockwise half a turn.  This made the machine cool to about 33 degrees then it shut off for 30 minutes going back up to 38 ....... I though perfect, but then within a few cycles it is back to it's 1:30 on 4:00 off cycle again.

Any ideas?

If it isn't harming the compressor then I suppose the 1:30 on and 4:00 of cycle isn't a problem, but I can't see it being good for it.

Thanks in advance.
Jeff

[Creighton]

Welcome Jeff!!
Are both door seals good? Same problem when full/empty of product? Eric at Global is the man on these issues. Have you tried giving him a call?
Creighton

[PC3239]

Thanks for the quick reply, the machine is full, have never run it when it is empty.  The machine has been restored (not by me) the seals, insulation etc are good.

[Jim]

Jeff,

Do you know if the refrigeration system has been opened and possible recharged...?

[PC3239]

Quote (Jim @ April 13 2006,9:15)

Jeff, Do you know if the refrigeration system has been opened and possible recharged...?

No, I don't know.  It looks like the compressor has been restored / replaced as it is in good shape and the electrical certainly is a lot newer then the ones I have seen in unrestored round top machines.  Cooling isn't a problem, I have the thermostat set at 1 right now and it keeps it at 38 degrees, if I put it down to 5 or 6 it cools to about 24 degrees.

Jeff

[collecture]

Hi Jeff,
Welcome. My first thought was that the compressor overload was kicking in and it was short cycling, but then I read that it was cooling down. A compressor should only start up 2-3 times in an hour. So with the compressor cooling properly, my best guess is that you have a faulty T-stat. I would try replacing it. As Creighton said though, Eric is the resident refrigeration guru - give him a jingle first.

[PC3239]

Well, I turned it off last night before I went to bed and then this morning I did more adjusting to the cut in and cut out screws.  I think I have mostly fixed the problem (just got lucky more accurately).

It is now cooling to about 30 degrees then sitting to 34 degrees then cooling back to 30.  It is cycling for about 4:30 on and 15:00 off, so coming on about 3 times an hour.  I can certainly live with this.  

I would prefer 34 degrees to 38 degrees, but it is stocked with beer, and I do love a icy cold beer, plus beer has a lower freezing point then Coke!!

 

[cvb141]

The evaporator coil needs time to defrost from the air blowing across the coil when  off on t-stat. Therefore you need the temp above freezing for a period long enough to defrost it. That is why they delay bringing the compressor back on till around 38-42 degrees.
Jerry

[PC3239]

Quote (cvb141 @ April 15 2006,1:01)

The evaporator coil needs time to defrost from the air blowing across the coil when  off on t-stat. Therefore you need the temp above freezing for a period long enough to defrost it. That is why they delay bringing the compressor back on till around 38-42 degrees. Jerry

I think I just ran into this problem, the machine was working great last night, went and checked today when I got home from work and it was running for about 30 sec, turning off for about 3 minutes and then running for 30 sec again, temp around 0 degrees.  Any ideas how I can get this to run a bit warmer, as I stated the thermostat dial has two screws one above it and one below it, I don't know which one is the cut in and which one is the cut out??? Any ideas?.  The thermostat is already set at 1 as warm as it can go.

Thanks

[globalcompressors]

Jeff,

 Have you simply tried a new thermostat? If not, that's where I would go first.
When you adjusted the "cut in and out" and there was not much of a change, then there may be something wrong with the part. They can, and do, go bad.


Eric

[PC3239]

Quote (globalcompressors @ April 15 2006,7:38)

Jeff,  Have you simply tried a new thermostat? If not, that's where I would go first. When you adjusted the "cut in and out" and there was not much of a change, then there may be something wrong with the part. They can, and do, go bad. Eric

Eric, I have considered a new thermostat, infact I have one that I bought a while ago for a Vendo 56 that I never ended up using.  Problem is I have no talent with anything electrical and the new thermostat I have has some type of plug on the end of it (funtronics part 10a), the thermostat in the machine connects directly to the compressor meaning I would have to cut wires etc.

Jeff

[davethebirdman]

Hello Jeff

Let me introduce myself. I am the man with ABSOLUTELY no electrical skills whatsoever. Everything I touch turns to rust.

That said. Even I have managed to change a T-Stat. Its easy Peesy. Just go to your local DIY store with your part and look for the connector that fits into it. Ask if unsure. You then cut the two wires and join your new T-Stat.

Instead of trying to guess whether you have turned the time up or down on your cut ins you can try a whole new T-Stat, which I presume is marked cut in and cut out.

I'll take a picture later of the bits that Wayne kindly sent me to do mine so you know what to look for.

I had exactly the same problem as you have with both my V-39's. There is a long thread on it in the Refridge section. Lots of help later and I have resolved it, I think. One of V-39's compressor cuts in for about fifteen minutes and then goes off for about 30 minutes an hour the other cuts in and out every fifteen minutes of so. I can live with that. I have 60 secs on 60 secs off for a while. That was only because the over-ride was cutting in.

Dave

[Yarochrehc]

Quote (globalcompressors @ April 15 2006,7:38)

Have you simply tried a new thermostat? If not, that's where I would go first. When you adjusted the "cut in and out" and there was not much of a change, then there may be something wrong with the part. They can, and do, go bad.

I'd try what Eric said, try changing the thermostat first.

[PC3239]

So can I just cut the wires from the old one and then attatch the new one?  There are two wires going to the thermostat  which leave the compressor, go up under that silver plate on the door frame and then into the thermostat.  The new thermostat has a two pronged plug which won't work with this compressor so if I cut the plug off and attatch the two wires to the wires coming from the compressor how can I tell which one goes to which???

Again thanks for your help and patience.

[Jim]

First, make sure the power is off, unplug the machine!
If you have a two wire system for the thermostat, I don't think it matters which wire terminates with which wire...

[SIGNGUY]

Let me know if this works as I havet the same problem with my 81 original Cooling system... I'll try the T-Stat replacement first... Here I thought I had a bad gasket problem but they are all new?  
Good advice..