# DIY habitat heating thermostat (temperature control)



## CosbyArt (Mar 10, 2016)

I stumbled upon a cheap way to make temperature controlled heating for my mantids, feeders, and other related needs - for only about $8 as I already had the heating source. With this type of setup you plug whatever heating device you prefer (heating mat/pad, heating lamp(s), etc) into the thermostat controlled power cord. Then position the thermostat near the heat source so it will turn on/off as needed to maintain the proper temperature.

The original idea I got from this youtube video for a chicken egg incubator; however, the idea has been around for a long time.  

I have provided the most accurate instructions I could for this diy guide; however, as I am not the one making it I can not guarantee that yours will function as described. In that regard this information is provided as-is. By using this guide you agree the author, and this forum, have no responsibility from any use or misuse that results for it.

Please read though this guide completely before asking any questions, as very likely you will understand it more thoroughly after reading. Then ask any questions you may still have.







*Materials Needed*


Water heater lower thermostat (I got mine locally at Lowes for $8.68) They are about the same price at other retailers, or online at Amazon or ebay as well.

Extension cord, power strip, drop cord, etc. Be sure it can handle the amperage (AMP) your heating device uses! (If you are worried about cord failure or fire use a heavy duty one)

Thermometer (I use a dual thermometer with a probe (Indoor/Outdoor style) to measure the temperatures in the habitat so I can adjust the thermostat for the best temperature range)

*Tools Needed*


Wire strippers

Utility knife (razor blade)

Screwdrivers (Slotted/Straight and Phillips)

_Optional_ - Nippers, good electrical tape, a soldering iron and solder, plumbers strap, or hot glue gun and glue sticks

*Step 1*






*Measure your cut -* You will want to measure down about 12" (30cm) from the multi-outlet end. This will give you room to set your thermostat where you need it, that way it can be adjusted to where it will properly turn on/off to control the temperature.

Of course feel free to move the placement around once you understand the instructions. For example on my large 10' (3m) cable I have it about 2' (0.6m) from the multi-outlet end).

*Step 2*






*Strip the wires -* Once you have measured where to place the thermostat you will need to carefully cut only one side of the cord, I used a pair of nippers to cut the one side of the cord (only one wire is cut). Then with a utility knife carefully slice the two ends of the cut section and pull it apart about 2" (5cm) on each side of the cut.

Next using wire strippers and strip the material off the wires, about 3/4" (2cm) of stripped wire is fine. Then twist the wire ends to prevent them from fraying. Optionally tin the twisted wires with solder, and form small bends in the ends afterwards to allow attaching to the thermostat screws easier.

Now is a good time to inspect the cord. Ensure the cord is free from cuts or nicks in the material, and no wires are exposed (besides the ends of course). If you find a problem area and it can be repaired/covered with electrical tape do so now; otherwise, replace the cord and try again. As the last thing you want is a short circuit from wires touching as it can cause a fire.

*Step 3*






*Wire the thermostat -* It's time to mount the thermostat to your prepared cord. Attach one of the stripped wires to one of the thermostat screws and tighten securely with a Phillips screwdriver. Repeat for the other wire.

Be sure that the wires are firmly attached to each screw, a nice and tight connection, and the wires are not frayed at the ends (especially make sure there are no loose wires bridging across and touching the other screws - that will cause the thermostat to be bypassed and the heating element will always be on).

Using a slotted/straight screwdriver adjust the temperature screw (the middle of the marked dial area) to the lowest setting (on mine that is 90 F (32 C) degrees). I did however find that turning the temperature slightly up from 90 F made my thermostat much more responsive to temperature changes.

Once you are finished I recommend double checking your work. That the wires are attached firmly and there are no bridge connections, or problems with the cable where it was cut and stripped.

*Step 4*

*Safety first -* This step is optional and is for added safety; however, be aware that touching either of the two screws on the thermostat itself will shock you with wall current/voltage when the cable is plugged into a wall outlet. This is also true if the screws are exposed to metal, water, or anything else conductive.

You can cover the two screws with layers of electrical tape across the front only. Do not block the temperature set screw (the dial area), or wrap tape onto the back of the thermostat (that is where the temperature is measured).

With a few strips of electrical tape directly over the screws you can further secure it with hot glue around the edges of the tape. I would not recommend you apply hot glue directly to the screw themselves as you may need to adjust them, or replace the thermostat cord at some time, and some hot glue (especially when it ages) can be conductive which will bypass the thermostat control.

*Step 5*






*Putting it all together with a heating source -* I recommend you first plug in your heating element in the thermostat multi-outlet cable end. In my case I am using a multiple goose neck lamp with 75w light bulbs (I will be replacing with a heat lamp soon). Place the thermostat near the heat source (for me by one of the light bulbs). Next make sure the thermostat screws have been safely covered (Step 4 above) and are not touching anything - in my setup the thermostat is upside down (bottom up). Next plug in the thermostat cable to a wall outlet (I personally use a fused/breaker surge protector for further protection).

Unless the temperature near your thermostat is 90 F (32 C) your heating source should now turn on.

Two things you should know so you can set this up correctly. First, the temperature reader/probe of the thermostat is inside the center of the back (I have drawn a arrow to it in the above photo). Second, the entire back portion is metal and as such will allow it to be placed directly on a flat surface to read the temperature. This is great to know if you have a glass or flat surface habitat like my cricket tank I have this connected to, the thermostat back/bottom can be directly attached to the glass so it can measure the temperature - this will prevent a breeze or wind from affecting the temperature reading.

Also the all metal back of the thermostat does not have electricity flowing through it, and can be safely handled. The only danger is in the two screws where the wires were attached to the thermostat on mine. If you have a multimeter or current probe you can test yours to ensure it is not electrified.

*Step 6*






*Adjusting the thermostat -* Now that you have your heating source hooked up to your thermostat cable, and plugged in, you will need to properly set the thermostat. For this you will need the aid of a thermometer. As placing the thermostat directly inside a habitat is not a option.

For my use, my cricket breeding tank, I need the temperature to be 80-90 F (27-32 C) for optional breeding and egg laying. I can say it has definitely made a difference in my crickets reproducing - the amount of eggs from 70 F (21 C) to the now mid 80's F (30 C) has nearly tripled their colony size.





This is a simple enough process to understand, but setting it can be challenging depending on how warm your heater gets, and how precise you want it to be.

To start I placed the thermometer directly on top of the screen mesh lid of my cricket tank to get a reading of the heat coming out of the habitat. As mine is a indoor/outdoor thermometer with a probe, I also placed the probe inside the habitat a few inches from the bottom (so nothing bothers the probe).

Depending on your setup you can mount the thermostat using the holes extended off the thermostat, hot glue the ends of the back plate to a flat surface, or simply let it sit (as I do). It can be mounted using a small wooden board to adjust it where it is needed, mounted using the habitat stand/table itself, or anything you can use.

There are two methods you can use to properly adjust the thermostat to get the temperature you need. Either you can move the thermostat itself closer/further away from the heat source, or you can place the thermostat nearly on the heat source and adjust the thermostat temperature screw until it turns off when the proper temperature inside the habitat is reached.

*Moving the thermostat - Method 1*

As the thermostat requires at least 90 F (32 C) to turn off, you will likely need to place it close to your heating source (especially if you need temperatures that are lower than that). As I use a lamp to provide the heat source I simply lay the thermostat upside down directly under the lamp to start.

I let the thermostat kick on/off the heat source multiple times to let it stabilize the temperature it provides. I found that it was too cold so I moved the thermostat away from the heat source a few inches (5cm) (in my case pulling up the lamp away from the thermostat resting on the table/stand), which allows the heat source to stay on longer. Then I let it sit awhile again, while it turned on/off multiple times to stabilize the temperature change.

If the temperature is too hot - move the thermostat closer to the heat source, making it stay on for less time (or for me by pushing the lamp closer to the thermostat). Let the temperature stabilize and adjust again as needed.

*Adjusting the thermostat temperature screw - Method 2*

Mount the thermostat directly near your heat source (in some cases it may be better to mount the thermostat directly touching the heat source). This can be done by placing the thermostat near/touching the heat source, attached with plumbers strap or hot glued into place.

Let the temperature build until the maximum habitat temperature you want is reached. Then slowly adjust the thermostat temperature dial screw until the thermostat turns off.

Let the thermostat then kick on/off a few times to let the temperature stabilize fully. If the temperature is too low turn the screw to a slightly higher setting - too high turn the screw slightly lower. Let the temperature stabilize each time, and repeat until the temperatures fall in the range you need.

*Final thoughts -* I found after letting it run a few hours and slowly adjusting the goose neck lamp bulb closest to the thermostat I got it to stay fairly consistent of a few degrees. As you can see in the photo above, the thermostat turns on when the habitat reaches 85.1 F (29.5 C) and turns off when it is 87.1 F (30.6 C).  

The only downside to this setup is the clicking/pop of the thermostat as it turns on/off; however, it sounds similar to a 24 hour light timer that turns their overhead light on/off daily and isn't a concern for me. Also depending on the temperature in the room they are in, it tends to turn on/off about once every 5 to 10 minutes.


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## Introvertebrate (Mar 10, 2016)

Nice work.  I saw that video about a year ago, but I figured the temperature range of a water heater thermostat would be too high for our purposes.


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## CosbyArt (Mar 10, 2016)

Introvertebrate said:


> Nice work.  I saw that video about a year ago, but I figured the temperature range of a water heater thermostat would be too high for our purposes.


Thanks. In order to get lower temperatures, you just have to place the thermostat closer to the heat source. If placed directly touching the heat source, temperatures of 70 F (21 C) or higher should be possible.


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## Introvertebrate (Mar 11, 2016)

Cool.  Thanks.


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## CosbyArt (Mar 12, 2016)

Introvertebrate said:


> Cool.  Thanks.


Your more than welcome, hope you can put it to use too.


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