controlling humidity in curing chamber

[Mmmm Meat]

I'm not sure how adventurous you are, but if you feel comfortable with basic electronics and some basic computer coding, you could use a simple relay and microcontroller (like an "Arduino") to trigger your fan for a 10 secs/hour cycle very easily (or any other type of cycle you want). Parts for this would literally be <$5 if you don't mind ordering them from China, and maybe even the same price or just a few bucks more via eBay. I can provide some guidance if interested.

Ha! It sound like fun, but I only envision headaches and frustration trying to save $20. I know nothing of relays. I was a dentist in my past life, Electronics was never my gig, My last physics class was in 1979 and I'm pretty sure I've forgotten anything beyond the basics.
I did receive and installed the second humidity controller on the fridge today and everything fell into place. I was definitely misinterpreting what was happening during the cooling cycles. It matched the above descriptions exactly. I was easily able to keep the small fridge within suggested curing chamber parameters for over an hour. The humidifier kicked on for a coupler minutes every 30 minutes or so. Dehumidifier seems unnecessary.
While I was playing with it, I happened to check Craig's List again - the clouds parted and the sun shone upon me. A new listing for a 17 cubic ft, frost-free Frigidaire refrigerator (w/o freezer) for $125 . An quick hour drive down into enemy territory (Portland) and back out before they knew what happened and I'm upgraded!
Rather than re-inventing the wheel, does anybody have guidance on where to create access holes for power/sensors on a fridge like this? It appears to have a circulation fan as there are upper and lower vents in the back of the interior chamber. I've seen where others have swapped out fans to reduce airflow on other types of refrigerators. Do you have any recommendations regarding this situation?
Once again, thank you for all your help.
George

 

[indaswamp]

A new listing for a 17 cubic ft, frost-free Frigidaire refrigerator (w/o freezer) for $125 . An quick hour drive down into enemy territory (Portland) and back out before they knew what happened and I'm upgraded!

Nice score....perfect! Freezerless models are hard to come by so you are indeed lucky to have found that one.

 

[indaswamp]

Rather than re-inventing the wheel, does anybody have guidance on where to create access holes for power/sensors on a fridge like this?

See my build thread for my old frigidare chamber...
https://www.smokingmeatforums.com/threads/dry-curing-chamber-build.295014/#post-2062255

Watch out for the condenser coils in the walls of the unit....take your time and go REAL slow...

 

[indaswamp]

I've seen where others have swapped out fans to reduce airflow on other types of refrigerators.

Not necessary for that unit, but what I did is flipped the plastic top vent cover 180* to angle the flow of air on the ceiling instead of directly on the salamis...

 

[Mmmm Meat]

Nice score....perfect! Freezerless models are hard to come by so you are indeed lucky to have found that one.

I know - I had a functional small fridge that would work fine, and I didn't really want to spend the money,.... but knew that I might not see another big frost-free without a freezer for maybe years. I spent an hour trying to talk myself out if it, but I lost the argument. Too good to be true.

 

[Mmmm Meat]

Not necessary for that unit, but what I did is flipped the plastic top vent cover 180* to angle the flow of air on the ceiling instead of directly on the salamis...

Great idea! Thanks for the link on your old Frigidaire - I'll check it out.

 

[Mmmm Meat]

Great idea! Thanks for the link on your old Frigidaire - I'll check it out.

So I did the alcohol and cornstarch trick to locate refrigerant lines in the refrigerator walls. It appears that they are only located in the upper 2/3rds of the unit.

Just curious if there is some reason why it wouldn't be better to put the humidifier/dehumidifier on the shelves of the door instead of on the floor? If the power access hole is drilled on the hinge side in the lower corner of the door, the power cables will slacken as the door is opened and should not create a problem.

I'm pretty sure that I'm safe drilling through the side in the lower third, but in my mind there is no risk at all in drilling through the door. This also opens up more floor space for dead bodies etc.

Comments?

 

[JC in GB]

Wishing you success on your curing chamber. I built one out of an old freezer that had a defunct compressor. I used thermoelectric modules for cooling. I only use it in the winter so I never have to worry about dehumidifying the cabinet.

indaswamp is 100% correct about the Marianski book. I think I have every book in the series now except the vegetarian sausage book. Haven't crossed that bridge yet.

My build is posted in the forums. Feel free to check it out if you like.

I may have missed someone saying this as it is a long thread but the Inkbird controllers should allow you to set the hysteresis points of the humidify/dehumidify cycle. This will allow you to tune the response of the controllers to the dynamics of your cabinet.

I like using a REX C-100 style controller for temperature control as it is a true PID and you can auto-tune the thermal response of the controller to your cabinet with a button press. I use this style of controller for my curing cabinet, charcoal smoker, and electric smoker. I am now in the process of putting together a DIY sous vide machine which will also be using this controller.

I have a few years of experience in electronics so if you have any questions about wiring or control systems, I will try and help.

JC