Danby DKC645BLS Temperature Control Bypass

[KillianBoy]

mustang_52,
Unless you are different mustang_52 that started this thread:

http://www.micromatic.com/forum/us-en/trouble-shooting-beer-quality-home/7614-need-some-help-balancing-my-system.html

you should still have a tower cooler, unless you stopped using it, but sorry when you post something, unless you post otherwise I assume what you post is still true.
By my understanding of Pismo10's bypass, it bypasses thermostat control, yet fools board into thinking compressor is on thus fan is on, if you are worried, just unplug fan connector on board, fan should stop permanently.
KB

[mustang_52]

Wow, you are pretty thorough! its cool. I was just baffled how you knew that. ill roll with it the way it is, just checking to make sure i did it right Thanks again for the help!

[KillianBoy]

mustang_52,
If not 1st time poster I usually check previous posts and see what happened before. From what other members who did this said fan stopped, you can double check and see, you might be hearing the tower cooler fan/blower running, if you are afraid about burning out fan/blower, turn off tower cooler in early mornings (as long as you want) and 15 minutes before (any time) pouring beer.
KB

[pismo10]

Now your only problem will be to be sure you don't freeze up your kegs..

[Xoloski]

"the fix" with a modification...

Just did this repair.
Not difficult.
I did make a modification that could extend the life of the compressor.

Once I realized the additional power cord ONLY provided 120VAC to the compressor, and once I realized most folks will use a spare 16 AWG cord to make the additional power cord that's needed, I decided to use a piece of 14/2 electrical cord and tie both of the two wires in the cord to the 120VAC + side of the electrical plug.

The new cord's doubled up 14WG conductors and will carry more current than a single 16 AWG conductor.
The neutrals and ground (bonding) wires are provided via the Danby cable.

I also installed the thermocouple through the existing hole for the CO2 and zip-tied it to the existing thermostat housing.

Good Fix...!

[chris218]

Buy this

Amazon.com: Johnson Controls A19AAT-2C Freezer Temperature Controller: Kitchen & Dining

1) Remove the red positive/+ wire from the tab on the compressor.
2) Make another power cord, the small prong is the + wire you need.
3) Put a tab on the end of the new wire from the small prong
4) Plug the new tab onto the tab on the compressor
5) Plug the new power cord into the remote thermostat you bought and plug it in. Plug the Danby's original power cord into the same outlet/ext cord
6) You are done

You do not need to touch the control board
You do not need to cut any wires/anything
This bypasses all that
Quickly and easily totally reversible
The built in thermometer still works.

Enjoy

Hey Pismo, by doing this mod, does the compressor constantly run?

[KillianBoy]

chris218,
Pismo isn't a daily member, so waiting for a direct reply might take a while, so in a nutshell, yes, if the new plug AND kegerator plug are plugged into an outlet, kegerator should run 24/7.
This isn't a bypass I would recommend, try the post #100 first if you have an old and/or used unit. The ONLY advantage of the pismo10 bypass is that it is non-invasive, if unit is new and can be returned no wires are cut.
Understand, this bypass is model specific (not brand), certain models are easier bypassed if needed, honestly if you don't have a electronic temperature controller, the best thing to try is the resistor trick (again model specific).
KB

[chris218]

Killian,
Thanks for the heads up!! I have 2005 used DKC645BLS. Not having any board issues yet. My only thing is the defrost cycle is annoying and takes forever. It gets cold fast and cools to about 35-36. I then put temp sensor in cup of water and it cooled to 30! Problem is then after an hour or so of being plugged in, defrost kicks in and climbs to 43-45 and wont cool again for roughly 35-45 minutes. Want to try pismo's set up with ETC to eliminate defrost cycle and keep kegerator at constant 34-36 degrees. Also post #100 in which thread are you referring to? Thanks bud!

[KillianBoy]

chris218,
Hate to say but it isn't a defrost cycle, just turning off the compressor.
Understand EVERY cooling unit will turn the compressor on, which will cool to the maximum either the cold plate or cooling fins will get the coldest it can get (cold plate will cool inside and air will blow across fins and into unit). Once cooling unit gets to temperature set by thermostat, thermostat will shut off compressor, once the inside gets to top temperature set by thermostat, it will turn compressor back on, etc.
With ETC it will do the same, maximum cold till set point or differential then turn off, then off till set point or differential, the cycle again. No matter ETC or stock thermostat, the unit will apply MAX COLD temperature, then turn off, temperature rises, then turn on. No regular commercial unit will apply a constant air temperature that is regulated by the thermostat.
The only difference between stock and ETC is that ETC will turn off and on more often (lowering life of the compressor).
The defrost cycle (after a lot of reading) is something manufacturers of these units put in to melt the ice on the cold plate, it extends the length of off cycle every 3rd of 4th, usually not every cycle.
The ONLY constant temperature you should be worried about is the temperature of the beer. You can get 34-36 constant interior temperature but at the expense of the compressor and price of an ETC and bypassing the board.
If you are worried about the beer, just put a 5 gallon bucket (cup of water don't cut it) of water inside, set to 36 degrees and wait to see what the water is in a couple of days, that should be the temperature of the beer, want it colder try the resistor trick.
Check out the Danby sticky from the beginning and my newbie thread for more information. Defrost cycle can be eliminated by turning unit off once or twice a day.
KB

[chris218]

killian,
understood! So whats the advantage of having the ETC? Like i said it seems like my defrost cycle comes on too fast. Plug unit in, it will cool to 36 which is what the display says. With a thermometer inside the fridge it reads 34(air) and 32 (liquid in cup). After about an hour after being plugged in and unit is reading 36 on display, the temp slowly rises, compressor comes on and climbs to roughly 45-50 and wont start cooling back down for a good 45 minutes. Is this normal operation? If so, i will go to radio shack and try resistor in temp sensor to just get it a little colder. It just seems to be a long time for compressor to be on while defrosting. The compressor is on during defrost correct?! Also, i ordered JC which pismo recommended, but what kind of power cord do i need to use? A simple 3 prong extension cord?

[KillianBoy]

chris218,
You really need to read the Danby sticky (post #100 is there), again I don't recommend the Pismo10 bypass, use the post#100, just need to cut wires and wire nut, no need to buy a new plug.
OK, my assumption was that compressor was off when temperature was going up. There is no mechanical side to the defrost cycle, it just extends the off period of the compressor.
If the cold plate doesn't stay cold while compressor is running, ETC/bypass won't help. Your problem might be deeper than the Danby thermostat, it might be low coolant.
A normal cycle for a kergerator is compressor on, cools down to low 30's, the compressor off warms to low 40's, then back. There is no heater that defrosts the cold plate, just an extension of the off part of the cycle.
Try not to obsess about the air temperature, again get a 5 gallon bucket fill with water, throw inside and run unit 2-3 days and see where that gets you. If it won't get 5 gallons of water down to 40 degrees, ETC/bypass will not help.
KB

[chris218]

33k or 100k resistor?

[KillianBoy]

chris218,
Search is your friend, I'll help you out by linking the page that says it all:

http://www.micromatic.com/forum/us-en/kegerators-and-kegerator-kits-home/1114-danby-temperature-modification-question-5.html?highlight=resistor+danby

Try 100 first and see, but honestly try the 5 gallon bucket test before doing anything else, again if your unit is getting warmer when compressor is running, it won't chill beer to below 40 degrees, some Danbys have actually cooled to 38 out of the box, just try the bucket test first before doing anything else.
KB

[psychodad]

The compressor will not be on during defrost. If you are concerned with the temperature on the display when the compressor comes on, then the resistor isn't going to do anything to help with that. The best way to control one of these Danbys is to bypass the controls and use an external temperture controller.

[chris218]

Psychodad,
So when it cools to 36 without any mods, then rises to 43-45 after an hour or so, compressor kicks on, this is ok?Yeah I bout analog jc controller.should be here tomorrow. What are your thoughts on pismo's old post of wiring it with another power cord. I have one from computer I threw out So ima use that. I bought the same controller as pismo!