My husband and I just started with chickens this year, and we plan to be away from home for the first time over Christmas (Dec. 23rd to 26th). We have 6 chickens in a 8x10 coop, which they like, so we're pretty comfortable there, but we still don't have a watering solution. It's been a little cold--Their water has only frozen a couple of times, usually when the level is low (they are using a 1 gallon fountain waterer right now). However, if it's cold over Christmas, we're going to need to do something to keep their water unfrozen. Our coop is 200'-250' from the house, so there's no way we can run an extension cord. I got a deep cycle car battery (will add solar, but I believe it should be enough for a couple of days at a time). We don't want to use an inverter and crank it up to A/C and high voltage, because of the risk of fire and efficiency losses.
Thus, the requirements for our heater:
-12V
-Low-power (to reduce fire risk)
-Immersible but safe when water is empty
I looked around but didn't actually find anything I liked. There are immersible heating elements on amazon, but they're typically pretty high power (150W+), which is an increased risk for fire or overheating.
The solution I am trying now is DIYing a heating element with nichrome wire. I used a nichrome wire calculator http://www.jacobs-online.biz/nichrome/NichromeCalc.html to determine that 42" at 28 gauge should do 15W and stay below 200F at room temperature (obviously I'd expect the water to be typically much less than that, but safety). I took a pizza tray that would fit in the bottom of a 5-gallon bucket and slathered it with food-grade high-temperature silicone sealant, placed the nichrome wire on top (with silicone-coated ordinary wire for connections already attached) & waited for it to cure (using a multimeter to make sure the wire wasn't shorted to the pizza tray... I should have waited for the silicone to cure before adding the wire, but I didn't). The wire didn't stick very well, so for the next step I ran silicone sealant just around the wire, covered with wax paper, then clamped another pizza tray on top to keep it flat. I let it cure for a bit, then pulled off the pizza tray and the wax paper (slightly before it was fully dry, so it stuck a little). I then waited for it to cure, then ran some more silicone sealant over to make the top waterproof as well. At this step, I also put the connection wires through silicone tubing to make them more waterproof/less likely to pull/break (not sure how necessary that is) and sealed the tubing to the overall object.
I waited for it to dry, and immersed it in water, testing with the multimeter to make sure it wasn't shorting to the water and that nothing wacky was going on. So far, so good--Now I need to actually hook it up to a power supply, and test and configure the temperature controller I got to keep it at just above freezing. I also need to put the horizontal waterers in the bucket (...and teach chickens to use horizontal waterers...).
The multimeter measures the heating element at 10 ohms, which at 12V comes to ~14.4W, which is about what I was aiming for.
Here's a photo of the object on the counter:
And here it is immersed in the bucket for the first test:
Any thoughts? Is this crazy? Will it work? I'll see with tests, probably (actually powering it is key of course). Please let me know of any safety concerns, in particular (I already purchased fuses and fuse holders for connecting to the battery [planning on using 3A] to reduce the risk if anything goes wrong).
Thus, the requirements for our heater:
-12V
-Low-power (to reduce fire risk)
-Immersible but safe when water is empty
I looked around but didn't actually find anything I liked. There are immersible heating elements on amazon, but they're typically pretty high power (150W+), which is an increased risk for fire or overheating.
The solution I am trying now is DIYing a heating element with nichrome wire. I used a nichrome wire calculator http://www.jacobs-online.biz/nichrome/NichromeCalc.html to determine that 42" at 28 gauge should do 15W and stay below 200F at room temperature (obviously I'd expect the water to be typically much less than that, but safety). I took a pizza tray that would fit in the bottom of a 5-gallon bucket and slathered it with food-grade high-temperature silicone sealant, placed the nichrome wire on top (with silicone-coated ordinary wire for connections already attached) & waited for it to cure (using a multimeter to make sure the wire wasn't shorted to the pizza tray... I should have waited for the silicone to cure before adding the wire, but I didn't). The wire didn't stick very well, so for the next step I ran silicone sealant just around the wire, covered with wax paper, then clamped another pizza tray on top to keep it flat. I let it cure for a bit, then pulled off the pizza tray and the wax paper (slightly before it was fully dry, so it stuck a little). I then waited for it to cure, then ran some more silicone sealant over to make the top waterproof as well. At this step, I also put the connection wires through silicone tubing to make them more waterproof/less likely to pull/break (not sure how necessary that is) and sealed the tubing to the overall object.
I waited for it to dry, and immersed it in water, testing with the multimeter to make sure it wasn't shorting to the water and that nothing wacky was going on. So far, so good--Now I need to actually hook it up to a power supply, and test and configure the temperature controller I got to keep it at just above freezing. I also need to put the horizontal waterers in the bucket (...and teach chickens to use horizontal waterers...).
The multimeter measures the heating element at 10 ohms, which at 12V comes to ~14.4W, which is about what I was aiming for.
Here's a photo of the object on the counter:
And here it is immersed in the bucket for the first test:
Any thoughts? Is this crazy? Will it work? I'll see with tests, probably (actually powering it is key of course). Please let me know of any safety concerns, in particular (I already purchased fuses and fuse holders for connecting to the battery [planning on using 3A] to reduce the risk if anything goes wrong).