Installing a temperature probe

[TANSTAAFB]

I have a magic chef MCBC580DBT beverage cooler that I use as a fermentation chamber. I use a Johnson A419 digital temperature controller to allow the unit to get warmer than the factory set 54*F. The thermistor wire is rather thick, so when run through the door gasket there is a large gap. I would like to install the thermistor permanently, but am not sure where to drill through the unit w/ out damaging something. When the unit is on frost develops on the back wall as a normal part of functioning, so I assume that is the only place there are cooling coils. I just want to be sure there is nothing in the side wall that would preven me from drilling through and using a rubber grommet to protect the edges of the drilled hole. Any suggestions or alternatives are greatly appreciated. Thanks for your help

 

[TANSTAAFB]

Anyone?

 

[dmfa200]

If you think about it, it's not a freezer. So it doesn't need much refrigeration coil to cool it.
I would say that the coils are isolated in the back as you have described.
A hole anywhere but the rear, and between the temp controller and the coils to avoid shorting out any wiring.

I'm not an expert. Just my opinion.

 

[kegtoe]

any pics TANS?

 

[TANSTAAFB]

I can do that...give me a few

 

[TANSTAAFB]

Kinda hard to see, but frost is starting to form on the back wall. The sides have slots to hold the glass shelves (removed for fermenting goodness!)

Close up of the gap in the seal with thermistor wire running into fridge

close up of frost on back wall

As you can see there are wires running everywhere, the Johnson unit is actually being held in place by a big magnet stretching over the wires. I want to deghettofy my rig!

 

[pvtschultz]

I saw a thread somewhere that stated to spread a mixture of corn starch and rubbing alcohol over the surface to detect where the condensing coils are. Spread the mix over the surface to be drilled and plug in the unit. The alcohol will evaporate quickly if there are any condenser coils near the surface.

 

[kegtoe]

the pic helps.

The corn starch is a trick that keezer builders use when drilling for the taps. You might also want to consider piercing the gasket, and sliding the probe through it, or simply notching the gasket. I think either of those methods would create less gap then what you currenlty hav now on that door.

I am concerned that there is frost building up. I would expect some condensation would be normal with that gap. that thing must have to run an aweul lot to kep temp.

 

[TANSTAAFB]

Outside grommet installed

Controller mounted on outside of fridge

And inside grommet

Thanks for all the advice. I just went on the assumption that there were no coils there because there was no frost. BTW, the frost is a normal part of this units function. When it cycles off the frost melts and drains. This is a $400 beverage cooler I scored at the local senior center thrift shop for $12 because THEY thought it was broken because it frosted up :rockin:

FIL gave me the A419 for my birthday, grommets cost $3, temperature controlled fermenting chamber w/ UV filtering glass door to watch my brew thump away like the telltale heart...priceless

 

[dmfa200]

TANSTAAFB

Looks great!
It is officially deghettofied.

 

[TANSTAAFB]

TANSTAAFB

Looks great!
It is officially deghettofied.

Thanks

Took me longer in the hardware store to FIND the stuff than it did to install it too!

 

[veritas524]

Does anyone have any more info on this fridge? I have the same model and I'm looking to stick a tower right behind the temp control but have read that there are two wires there. I'm also going to try and bypass the compressor relay so I can get this sucker to drop into the high 30's. Any info would be appreciated.

 

[Normalicous]

What type of bucket is that you are using with the blue lid? Sorry, I am a noob

 

[TANSTAAFB]

What type of bucket is that you are using with the blue lid? Sorry, I am a noob

I think it's a True Brew bucket. Just happens to be the 6.5 gal #2 HDPE food grade bucket brand my LHBS carries but any will work...lots of Ale Pails out there!

 

[Matthewjscott]

Could this fridge with the Johnson Controller easily and consistently hold around 60?

 

[TANSTAAFB]

Absolutely. I still use this set up as my primary ferm chamber and regularly have it set to 64-65. I recently made my first foray into lagerish brewing by making a California Common like Anchor Steam using their yeast strain that I fermented at about 60. It does take a while to get the temps down that low in 5 gal of wort if you pitch higher and rely on the fridge to get you to fermentation temps. With the Johnson it stays right where you set it though.

 

[Matthewjscott]

Did you bypass the OEM thermostat or just use the Johnson controller connected to the power cord

 

[TANSTAAFB]

Just use the Johnson. A hack seemed like too much work and the controller just turns it on and off.