Chest Freezer Alarm

Hey guys,

I bought a kenmore chest freezer (model 253.16592102) off craigslist and it has an electonic control pad on the top. I'm using an inkbird itc308 temperature controller and every time it turns the freezer on the alarm goes off until the freezer turns off.

It's driving me absolutely insane. According to this thread i found the alarm doesnt actually appear to be on the top lid of the freezer (glad i didnt go ripping it apart yet) but is built into a control pad next to the compressor on the bottom? The only other thing i can see is there is a wire that goes to the lid to power the light, control panel and whatever else. Could i just unplug this (actually i'll have to anyway in order to install a collar for a keezer build, or at least extend it somehow)? Although im hesitant to stick my hands in there as i'm not sure what could shock me. Do freezer compressors have capacitors that hold power long after it's unplugged? I've heard stories of technicians and old CRT monitors ehh.

The only other thread i found was here which wasnt all that helpful and a couple diagrams here and here.

Oh and i did see it takes a 9v battery for the alarm. I put one in and then instead of beeping every 3 seconds while the freezer was turned on it just beeped once every minute endlessly, regardless of the freezer running or not. Stupid designs i tell ya.

Appreciate any help i could get before i take my 8lb sledge to this gigantic freezer the next time it wakes me up

 

I know your feels....mine often goes off I go out and look and its friggin fine... the joys of homebrew I guess...

 

I'd be looking for the noisemaker itself and snip those little wires going in to it.

 

Well according to the thread i linked the buzzer is built into some control pad near the compressor. I'm not sure if snipping the buzzer attached to a board would destroy the board, assuming i can even find it.

I'm more interested if i can just unplug the power plug that goes to the top lid itself (since i'll have to do that anyway in order to install a collar). But before i do i need to know if its safe to stick my hands in there, if there are any capacitors that hold power after its unplugged. Or if there are any other reasons not to unplug it.

 

There's nothing in the lid but an incandescent lamp and a switch.
You can certainly disconnect the interconnect at the back of the lid - and even leave it disconnected - without issue (other than the interior lamp won't light)...

Cheers!

 

Sweet good to know about that. I was wondering if it would work because as far as i can tell the temperature control (which is on the lid) reads 10F when the unit turns on thus turning the compressor on. Without power going to the lid i wasnt sure if it would know to turn the compressor on.

Anyone experienced know if its safe to stick my hands in there as long as i unplug the freezer, ie is there a capacitor that doesnt discharge quickly?

 

Wait - there's a temperature display in the lid? In that case I'm off-base.
I've built two keezers that had interior lights and other than the lamp/holder and a mechanical lid switch there was nothing else in either lid.

If you actually have the display up there there must be more conductors running through the lid interface than the three my freezers had.

Sorry 'bout that...

Cheers!

 

So what does that mean "more conductors"? Can i remove the interconnect power plug? I posted the diagrams i could find but im no electrician (something i intend to remedy in the future in order to make an electric brew system though).

 

Well, this is the harness that runs up to the lid


So a lot more wires that I've seen before.

And this is the front of the control board


And you can clearly see the round black buzzer.

So is that display mounted in the lid or on the end near the compressor compartment?
Wherever it is, that's what you need to hack.
If you're reasonably handy with a soldering iron you can remove the buzzer completely...

Cheers!

[edit] Curiously - and perhaps totally unrelated to the task at hand - there's an FCC registration in the silk screen on that controller.
I wonder why...

 

The LED readout is on the lid. There is a control box next to the compressor where the wires come from though.

The notsohelpful tech in the thread i posted said that to get to that box would require taking the whole lid apart to get to and snapping some plastic rivets. Why cant they just use screws...

In the meantime i had a stupid thought. I just put some weights on the reset button and when the compressor turned on it actually worked. Beeped once then went off.

Though when i get around to putting a collar on i'm still going to need to do something about the cable. Only giving a few inches of slack.

Thanks

 

It may have to do with radio frequency pollution. One reason why PC's used to be enclosed in metal cases was to prevent RF interference from leaking out and screwing up radios and phones and such.

The controller may have had to pass RF leakage tests or some such. Just a guess....

 

Took a few pictures if it helps.






Yeah pretty nasty in there. Was a dead mouse in that compartment when i opened it. The main compartment was fine though, only a few small rust spots, much better than others i've seen.

 

Any other ideas? I would still like to know whether i can unplug that interconnect and whether it's safe to do so unplugged (any capacitors).