My curing chamber has been working very well for a very long time, but just the other day I decided to make a small change. I've had a bulb in the fridge, on a dimmer, which generates heat to force the fridge to cycle more often, lowering the humidity. This is especially useful in winter when the fridge isn't cycling as often and when a new batch of product is added, which is losing a lot of moisture.
The bulb has worked well, but I've read a lot about how light affects fat and speeds up the oxidation. I'm not sure I've experienced this, but I've read it and heard it from so many sources I figured it must be accurate. To address this I replaced the bulb with a non light emitting ceramic heater used in reptile cages. It plugs right into a bulb socket and can be dimmed just like a bulb. It's perfect!
So far I like it. My chamber was running around 83% RH after I put my latest batch of salame in, which is a touch high. I turned the heater on real low, and it's now around 78-80 which is good; and no light!