fermentation chamber performance

Ive recently completed a fermentation chamber build.  I build a box around a mini fridge such as this:

http://www.amazon.com/Sanyo-SR-3770S-Counter-High-Refrigerator-Stainless-Steel/dp/B000260JRG/

lined the box with 2 inch thick, r10 foam board, sealed all cracks with spray foam, then taped all joints/spray foam areas with aluminum tape.  The inside of the box measures 41 inches long, 26 inches wide, 29 inches tall on the inside.  It is temp controlled by a johnson controller.  I turned it on this morning and set the controller to 34 degrees to see how it would handle it.  About 9 hours later, i checked it and it was at 42 degrees.  I dont beleive it ever got down to 34.  Id like to crash cool around 34, but its looking like that wont be possible.  Is this about the normal limits of mini fridge builds like these?  Im just curious how others perform.  I don’t currently have any fans in the chamber, think that would help to circulate the air?

Thanks!

Pics!

Try a fan and pics would be nice.

I don’t think most refrigerators are built to cool down to 34 degrees as very few goods are really stored that cold. I just don’t think they are strong enough.  High outside temps will make it work harder.  A fan will definately help and make sure the temperature probe is not near the cooling parts.

Did you test it to see if it would get that cold before you added the ferm chamber? If so, then a fan would help somewhat.

Yes, 42 is about the best you can get with a mini fridge. Even some semi expensive kegerators only get to 40-42.

The chamber that I built on an old wine fridge holds two carboys and I can get it down to about 38 degrees there is a computer fan int there as well.