Kegerator via Craigslist- crash course in appliance diagnosis?

[a_gunslinger]

New to me, older Danby Singlt Tap Kegerator (Model # DKC645BLS). Found it on Craigslist. Before I went to see it I asked the owners to plug it in night before to let it cool, and to put a glass of water in it, so next day I could test ambient air temp and temp of the water. When I get there the manufacturer's digital guage on front reads 36. But temp of water is 43, and put an air thermo in there for a while and it bottoms at about 43.

She had no idea about age but guessed maybe 7-8 yrs old. I could tell she literally knew nothing about it. She has been going thru her fathers stuff over past year. But I notice sticker on compressor says 2005. Its in very good cosemtic shape.
She could tell I was hesitant if it couldnt reach my needed temp. And she was very nice, and trusting, and said I could take it with me and if I got it to work send her the money!

Its clean enough I felt compelled to see if I can resolve temp issues, but I know nothing about appliances, and dont really need another project. Hoping maybe just the thermostat? And is that the white box upper right interior?

So symtpoms/observations:

1. Overnight left on in thier garage. Night temp low of about 38, so garage probably ~45 all night.
2. Digital fridge panel showed 36 on arrival, but my digital thermo placed in fridge only went to 43, water temp was 42. So it must be cooling.
3. Interestingly, when I opened the door and left it open compressor didnt come on. I assumed it would as interior temp raised.
4. I unplugged the fridge for a few minutes and plugged it back, expecting to hear compressor startup and make some noise. But nothing.
5. Once it did start to whir quietly, but not at a time I would expect it to try and cool (when door open and when first plugged in).

So there I am. Any guidance hugely appreciated!

 

[day_trippr]

It would not surprise me if the oem thermostat on a mini fridge wasn't all that accurate, but still, it's worth doing a solid test on the compressor/cooling system.

You can do that by first disconnecting the line cord from the AC outlet, and removing that cover to expose the mechanical thermostat. It will have three wires plus a thin tube, typically sporting a thin white plastic jacket. That's the capillary tube that runs between the bulb at the other end and the thermostat. Try not to damage that tube for now.

One of the wires will be green or green with a yellow stripe. That's the safety ground for the thermostat. Leave that attached to the metal thermostat housing, there's no need to remove it. The other wires will likely be black and red. The black would be the AC "hot" lead, the red would be the "AC Switched" lead on the way to the compressor. Remove those two wires, connect them together, and make sure there's no exposed wire (wrap it in tape).

Finally, plug in the line cord - and remember there's literally nothing that's going to stop the compressor from running (ie: don't go out to dinner )
I would stick a fridge thermometer in there and check it frequently and try to compare what's happening to when the oem thermostat was still running the show...

Cheers!

 

[estricklin]

The compressor may not kick on immediately when you plug it up, that's a protection some units have so that in case of a power outage, the compressor won't be damaged by short cycling.

They don't always kick on immediately when you open the door, it can take a minute for the capillary inside the thermostat to change temperature enough.

I'd jack the thermostat all the way down, or I'd simply wire around it temporarily to see if it's cooling well or not.

 

[a_gunslinger]

Update. Havent had a chance to to full test. But it seems to be working for the most part. Not sure if it was just groggy from long period of no use? Remaining issues/questions:

1. The digital dispaly is always off relative to the themrometer I have in the kegerator - always 4-5 degrees collor in kegerator than the digital dispal they reflects. Not a huge deal. And the amount off is never quite pfredicatbaler (ie 30 deg interior doesn not always mean 42 on dispaly, might be 43 or 44)
   
   
2. The small computer type fan in it to circulate air has started making racket each time it fires. Almost sounds like the plastic fan blades are hitting the fans case, but when I took it out I see no contact. Might replace it just to see. Upgrade it?
   
   
3. Back panel gets a little icy.

Still plan to run the full testday_trppr suggests.

 

[a_gunslinger]

Finally got around to looking at tis. Wanted verify Im connecting the correct two wires ;^) Red and black below. Fridge is cooling but the inside (using digital thermometer) just never matches the OEM digital display on exterior.

 

[day_trippr]

That is not the thermostat, that is the start relay. The thermostat is inside the cabinet...your third picture shows it...

Cheers!

 

[a_gunslinger]

Good think I checked huh! Appreciate the help.

That third picture turns out to be the small circulation fan. I have the large white refrigeration plate in the back. Assume its behind this if I gently pull it back?

 

[bruce_the_loon]

Here is an exploded parts manual for the kegerator.

http://www.reliablepartsinc.com/danby/Wine & Keg Coolers/DKC'S/DKC645BLS.pdf

 

[a_gunslinger]

Thanks for schematic. Based on the archic looking drawing, I guess I can be confident this isnt just a few years old. And maybe the 2005 model as indicated on the compressor sticker If Im reading this right its part #8, and appears to be behind the cooling plate in back.

Its cooling just unpredictably. Defintiely not holding a temp, but usually within a few degrees. Freezer hovers around 40. Lowest the digital will go to is 36, so I cant set it for 34 hoping to hit 38.

Didnt pay much for it so cant complain. But wondering if analog conversion might allow temp lowering?

 

[aaronmq]

I used to have one of these and the temperature problem was common with this model. There was a way to add a 100k resister to the internal temperature probe that would solve the problem. I can't seem to find the thread, but I'm sure a google search could help you out. IIRC, you take off that little plastic cage and you can find the temperature probe inside it. You pull the probe off the small harness, and then you can then jam the resister wires into the harness before reconnecting the probe.

 

[a_gunslinger]

I used to have one of these and the temperature problem was common with this model. There was a way to add a 100k resister to the internal temperature probe that would solve the problem. I can't seem to find the thread, but I'm sure a google search could help you out. IIRC, you take off that little plastic cage and you can find the temperature probe inside it. You pull the probe off the small harness, and then you can then jam the resister wires into the harness before reconnecting the probe.

Thanks for the reply! Im not sure that plastic cage (upper right) is temp probe. Thats the small circulation fan under there.

 

[aaronmq]

Thanks for the reply! Im not sure that plastic cage (upper right) is temp probe. Thats the small circulation fan under there.

Ahhh, the probe is to the left towards the bottom.

 

[a_gunslinger]

Ahhh, the probe is to the left towards the bottom.

Got it. Must be behind the cooling panel coverign the back wall.

 

[bruce_the_loon]

Can you post a photo of the left side of the fridge?

 

[a_gunslinger]

Can you post a photo of the left side of the fridge?

Yep, Im an idiot. There is a cage bottom right. Thats must be my probe. Going to see if she works a little better in a glass of water. I found the old threads on the bypass or new resistor. A little gunshy to try, it but may. With two kegs in there, and digital thermo at 36, I can never get past 42.

Danby DKC645BLS Temperature Control Bypass - Dispense Forum | Discuss Keg Beer, Kegerators, Wine On Tap, and more!

 

[a_gunslinger]

I used to have one of these and the temperature problem was common with this model. There was a way to add a 100k resister to the internal temperature probe that would solve the problem. I can't seem to find the thread, but I'm sure a google search could help you out. IIRC, you take off that little plastic cage and you can find the temperature probe inside it. You pull the probe off the small harness, and then you can then jam the resister wires into the harness before reconnecting the probe.

Found that old thread ;^)

Danby DKC645BLS Temperature Control Bypass - Dispense Forum | Discuss Keg Beer, Kegerators, Wine On Tap, and more!

 

[IslandLizard]

Found that old thread ;^)

Danby DKC645BLS Temperature Control Bypass - Dispense Forum | Discuss Keg Beer, Kegerators, Wine On Tap, and more!

Can you please recheck that link, it leads to a "site can't be reached" error here.

The following link points to something similar, but is it the correct one?
https://www.micromatic.com/forum/us...11-danby-dkc645bls-temperature-control-bypass

 

[a_gunslinger]

Can you please recheck that link, it leads to a "site can't be reached" error here.



The following link points to something similar, but is it the correct one?
https://www.micromatic.com/forum/us...11-danby-dkc645bls-temperature-control-bypass

Corrected link: Danby DKC645BLS Temperature Control Bypass - Dispense Forum | Discuss Keg Beer, Kegerators, Wine On Tap, and more!

Probably several threads as it was a common issue.

 

[IslandLizard]

Probably several threads as it was a common issue.

It's the same thread, yours links to Page 3, mine to Page 1.

 

[aaronmq]

Yep, Im an idiot. There is a cage bottom right. Thats must be my probe. Going to see if she works a little better in a glass of water. I found the old threads on the bypass or new resistor. A little gunshy to try, it but may. With two kegs in there, and digital thermo at 36, I can never get past 42.

Danby DKC645BLS Temperature Control Bypass - Dispense Forum | Discuss Keg Beer, Kegerators, Wine On Tap, and more!

View attachment 713968

I never had luck with the probe in water. The resistor was so easy and worked like a charm though. But it looks like you are on the right track. You definitely have options.

 

[Misplaced_Canuck]

Pardon the interruption... But why are you drinking your beer so darn cold? I keep my fridge at 52F for ales!

MC

 

[spbagwell]

@a_gunslinger I found the same kegerator model on Craigslist in 2014. The controls on the display could no longer adjust the temperature, but the kegerator worked for about a year before the temperature started cooling to just 60 degrees. I installed a resistor to help lower the temperature to 39-42 degrees. (I did not bother trying to replace the control board as they were prone to failures.) I agree with Misplaced_Canuck that the temperature you have now is sufficient, but we all have different preferences. The only issue I have experienced with the kegerator since then is that the compressor stopped turning on in 2016. After replacing the compressor starter resistor ($7 on Amazon), the kegerator has since worked as expected. (Replacing the resistor seemed to be a common fix.) Other changes that I have done is converted the single faucet tower to a triple faucet tower by drilling additional 7/8" holes and installed a keg tower cooler ($33 from most beer websites). I keep two 5 gallon Cornelius kegs and a 2.5 gallon keg in the kegerator. Your picture shows the CO2 tank inside - mine has a port to run the gas line in from the back. With the CO2 tank outside, this enabled the addition of a Taprite 3 Body Secondary Regulator so I could force carbonate while still drinking from the other kegs or just have 3 different beers to drink.

PM me and I can send you a resistor that you can use if you decide it is necessary to make the modification. It is an easy process, and they come in a pack of 5 so I have extra resistors.