[Philbrew]

In past I've heard folks recommend a reptile heater for heat in a fermentation chamber. 

What kind?  How much wattage?  How to install?  Dos and don'ts? 

My chamber is an old 15 cu. ft. fridge (upright w/freezer at top).
Edit:  Freezer is separate compartment and door.

[Thirsty_Monk]

It is ceramic reptile heater. It screws to regular light bulb socket. Depending on size of your chamber 60w should be good start.

http://www.amazon.com/gp/aw/d/B017RCQ4JO/ref=mp_s_a_1_8/176-8445951-7936365?qid=1458524458&sr=8-8&pi=AC_SX236_SY340_QL65&keywords=reptile+ceramic+heat+emitter&dpPl=1&dpID=314cLLa0yEL&ref=plSrch

http://www.amazon.com/gp/aw/d/B017RCQ4JO/ref=mp_s_a_1_8/176-8445951-7936365?qid=1458524458&sr=8-8&pi=AC_SX236_SY340_QL65&keywords=reptile+ceramic+heat+emitter&dpPl=1&dpID=314cLLa0yEL&ref=plSrch#immersive-view_1458524651103

[Pricelessbrewing]

Out of stock right now, but you can order custom sized ones here http://www.reptilebasics.com/heat-tape for a bit cheaper.

[Stevie]

It is ceramic reptile heater. It screws to regular light bulb socket. Depending on size of your chamber 60w should be good start.

http://www.amazon.com/gp/aw/d/B017RCQ4JO/ref=mp_s_a_1_8/176-8445951-7936365?qid=1458524458&sr=8-8&pi=AC_SX236_SY340_QL65&keywords=reptile+ceramic+heat+emitter&dpPl=1&dpID=314cLLa0yEL&ref=plSrch

http://www.amazon.com/gp/aw/d/B017RCQ4JO/ref=mp_s_a_1_8/176-8445951-7936365?qid=1458524458&sr=8-8&pi=AC_SX236_SY340_QL65&keywords=reptile+ceramic+heat+emitter&dpPl=1&dpID=314cLLa0yEL&ref=plSrch#immersive-view_1458524651103

60w is totally fine, but often more expensive than the 100w on Amazon for some reason.

Also, they are designed to be used with the cage style fixture. The normal style radiates to much heat back at the bulb and could cause issues with lifespan, possible cause it to overheat. Maybe I'm just overly cautious.

Zoo Med Wire Cage Clamp Lamp https://www.amazon.com/dp/B0002DIWVO/ref=cm_sw_r_cp_awd_Yw17wb847WH9W

[reverseapachemaster]

Out of stock right now, but you can order custom sized ones here http://www.reptilebasics.com/heat-tape for a bit cheaper.

This is what I use but is more like fermwrap than the ceramic heaters otherwise discussed in this thread. I am very happy with this product and using it inside my small fridge fermentation chamber I can raise temperatures to anything I might need.

I looked at the ceramic reptile heaters at one point but decided I didn't like it for my fermentation setup. I was concerned about uneven temperature and the risk of fire.

[toby]

I use one of these with some 3M Command Outdoor hooks (120F tolerance) to loop it around the interior of my chest freezer.

http://www.amazon.com/gp/product/B0002DIWMS/

The advantage is that it is made for use inside terrariums, so it warms without getting hot to the touch.