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What do you think about using one of these for a incubator??

Its a ThermoKool MR-138 mini heater/cooler with digital tempature lcd, you can set it for the exact tempature you would like; 86, 89 or whatever and its suppose to hold the temp very accuratly.

I dont know if I would fully trust it so if I were using it as a incubator I would probably add a extra thermostat w/ probe

The unit has a fan system that you can see in the picture, bottom is the inlet where the heated/cooled air comes from and the top is the outlet. Fresh air exchange.

Seems like a pretty good set up, tweek it a little bit to make it more for our purpose as a incubator and should work good, right?

Add a extra thermostat and maybe put a water container/tray on the very bottom to give more humidity

www.cyberguys.com/templates/print_searchdetail.asp?productID=5904&ta=&core_cross=

www.thebuzzelectronics.com/thermokool_mr138_thermokool_mr-138_deluxe_mini_cooler_and_w.htm

www.hometreats.com/pd_deluxe.cfm

It's not too different from my incubator, but you would probably have to use another thermostat with it. I don't know how accurate the one that comes with it is. My incubator is a thermoelectric wine cooler. All I did was reverse the polarity to the thermoelectric unit and hook it up to 2 Johnson thermostats. For a little more money than what you're looking at you could do that and have more space. Let me know if you want to know exactly how I made mine.

Hope this helps,
Shelly

Very nice!! What are the dimensions of your incubator? When you say you reversed the polarity, does that mean that instead of cold air the unit now supplies heat? When incubating eggs do you place a water container/tray inside the incubator to up the humidity? What did your incubator cost you to build?

I think it's about 28"h x 18"w x 20"d. I can get at least 6-8 clutches in it...I'm going to play around with it once it's empty to see if I can fit more.

Yes, reversing the polarity makes it heat instead of cool. Thermoelectric units are designed to do both; the direction that the electrical current is flowing determines if it heats or cools. I'm not sure how well you can see the wires in this picture, but there's a red wire and a black wire going to the unit. All I did was cut them, cross them, and splice them back together (red to black). Then all you have to do is hook it up to a thermostat and you're good to go. I'm using double Johnsons. You need to use an on/off thermostat with thermoelectric units. If you need better pictures of the wiring I can take some as soon as my last clutch hatches. They're due in about a week.

The wine cooler cost about $140 (it was new, but had a small scratch), and the thermostats were $60 each. I bet you could find a used wine cooler if you looked, just make sure it's thermoelectric. It already has a fan, too, so you don't have to add anything. The only thing I may do differently next season is stand the whole thing upside down. The fan and heating element are at the top, and I would rather have them at the bottom since heat rises. I don't worry about the humidity in the incubator since the eggs are in shoeboxes with perlite and water.

Sorry that was so long...I hope it all made sense. The wiring is really easy (even I can do it, lol).

Hope this helps,
Shelly

Wouldnt it have been more cost effective to just do away with the thermoelectric unit, use a linear heating element such as Fexwatt, and then just use one proportional controller?

Beside, I would think, set in the on/off mode, you would get a very wide hysteresis from the target temperature on either end of the set points- no?

I am not critisizing, in fact your setup is very intelligent and well done, I am just curious.

Nice job though. Do you work with electronics? I used to and you seem to know what you are talking about?

~Alan

Actually, I was planning on backing the proportional t-stat up with an on/off t-stat anyway so it didn't really make a difference in the cost. I bought the wine cooler with the intentions of just using flexwatt to heat it (I wanted a glass door), but my dad and I thought we would play with the thermoelectric unit just to see what would happen. It worked really well so we just left it like it is now. It actually is much more stable than I thought. It holds a temp within 0.3F inside the egg box according to my thermometers. I think that's because I have the main thermostat probe outside the egg box, and the backup inside the box.

And, I'm not the one with the electrical experience. My dad is an engineer, but he won't just wire stuff for me. He makes me do it so I learn how, lol.

You are right, though, this isn't the cheapest way to make an incubator. Of course, once all the eggs hatch you could always uncross the wires so it cools again and fill it with wine to celebrate. You can't do that with flexwatt

~np!