The other day, I saw some nifty directions for making a chicken water heater out of a cookie tin and a light kit . Since my husband, Greg, is an electrical engineer, he likes me to ask him before I begin projects like that. So, I asked. He said, “Let me think about it.”
A short while later, he was teaching me about resistors, Ohm’s Law, and how to calculate how much power a 60 watt light bulb uses. He showed me a website, mouser.com, that sells electronic parts, this is where we ordered our resistors. Then, we made a trip to Radioshack for heat shrink tubing. A flexible bucket was found to use as a cement form. He dug some old electrical cords and pieces of aluminum out of his treasure stash. The goal was to make a more durable water heater that didn’t require bulb changes. According to my math-story problem, the 470 Ohm resistor would only need half the power to produce not quite twice the heat.
When the resistors arrived, the old electrical cord was cut, peeled, and split into two ends. Each end was wrapped into one of the two metal pieces on opposite sides of a resistor. With the resistor on a tile trivet, the new circuit was plugged in for testing. Greg used his handy laser thermometer (he has SO many fun toys!) to compare its temperature to that of a 60 watt light bulb burning in the bathroom. The outside glass of the light bulb measured close to 140 degrees Fahrenheit; the resistor was a winning 250 degrees Fahrenheit. (You may see more than one color of electrical cord, because more than one heater is being made.)
With that verified, he proceeded to solder the wires into place. Then, the heat shrink tubing was cut and placed over the soldered joints. My heat gun (which was originally intended to emboss stationery…) blew hot air on the tubing to make it tighten up and add stability to those points. Next, he bolted the resistor set-up to an aluminum plate which should help radiate heat to the water.
Now, he wanted me to do more than operate the camera. I was guided to collect about 2 inches of road mix (conveniently laying around in the side yard), measure out cement that was approximately one-fourth the volume of the road mix (whatever left-overs he had around) and dye (not necessary, but available), and cut two round pieces of fiberglass mesh (he likes to play with fiberglass, too). The mesh would make the concrete stronger and less likely to crack. Greg handed me his usual rebar stirring rod to use as I added the dry cement mixture, a portion at a time, to a bucket with water in it. I quickly decided that he needs a better cement stirring spoon for Christmas! (He has a small cement mixer, but this was too small of a project for that.) Along the way, he tossed in some hair-like fiberglass fibers, for even more thorough concrete bonding; and we added more dye; he added a little more water, keeping the consistency to a thick sludge. It was officially concrete now.
He finished mixing, because my arm was giving out, but I was able to do a lot of the layering of concrete with the circuit in the form bucket. After an initial layer of concrete, we positioned one of the mesh circles. A bit more concrete was put on this. Greg showed me how to give it all a gentle wiggle now and then to help things settle. The resistor combo was put in, with the cord held in a block of foam by a small slit. Hopefully this would keep the cord to the edge during the hardening time, and make it easier to do repairs later, if needed. Finally, it was all covered with one last layer of concrete and tamped carefully with a wooden block.
A few days of sitting in the semi-warm greenhouse, and the heating stone was ready to come out. I cautiously bent the sides of the bucket to free the stone, but it was heavy enough that I accepted Greg’s offer let it slide out onto his hands. We plugged it in again and measured the outside temperature of the concrete to be 88 degrees Fahrenheit! Perfect.
The side that was on top in the bucket was a little knobby, but was placed toward the ground. Since I just put it on dirt, it was easily leveled. The other side of the stone was smooth, with one little concavity where the plastic bucket was warped. The chicken water dispenser sits on there nicely.
This morning, with an early morning low of 23 degrees Fahrenheit, the chicken water heating stone was just warm to the touch. Most importantly, the water was liquid and the chickens are drinking it. This set-up stays much cleaner than the open, heated bowl I was using previously. The stone not only heats the water, but keeps it up above ground level. I’m sure it is much more stable than the cookie tin heater would have been. It was a fun guided experiment, well worth the extra time and studying!