I purchased a Brower Top Hatch TH120 incubator in March, 2001, from Wings N Things Hobby Farm (great prices and nice people). See my photos CLICK HERE (NOTE: photo's are located on a webtv server, they may take time to load. There is a link back to here on the 2nd page. Soon as I figure how to can grab the pix from webtv I will resize and upload them to tripod)
The first TH120 I received apparently had a thermostat problem, and I could not get the temperature to stabilize. I returned it without a problem, and had another shipped out as a replacement.
The incubator was very easy to clean there was some residual manufacturing oil and debris on it, so I put all the parts except the motor base into the dishwasher. Very simple, clean, and efficient. I really like this feature. I noticed the incubatorıs turning motor was very loud at first, much louder than a running refrigerator. As the gears broke in over the course of a day or so, the noise lessened considerably, though itıs still a tad louder than a fridge.
For temperature and humidity control, I used the glass thermometer that came with the bator in conjunction with a digital thermomether/hygrometer I purchased from a scientific company Technika - for $35. I laid it across the turning rack per Browerıs instruction booklet, as I did the glass thermometer. Itıs a little on the awkwardly large size, so I helped support it by stringing a wire between the two bars. As with all thermometers, there is a possibility of inaccuracy, so I have decided to use the glass thermometer as a base mark and check it with the digital. Absolute accuracy in humidity is not as important as absolute accuracy in temperature, so Iım happy with the ease of use and donıt mind its standard deviation of 6%. These take up room in the bator, but Iım not hatching a great many eggs.
After reading Macıs comments (on previous page) on its temperature sensitivity, I copied his method by Scotch-taping bubble wrap to the outside of the bowl, bubble side in, and surrounded the whole thing with an open topped box. I set it up and let it run without touching the thermostat over the weekend. I kept a recording thermometer near the bator, and checked it every few hours, and checked its overnight low in the morning. Although I felt the location was in a stable environment, it still varied too much ranged from 63.8 degrees to 74.3 degrees Fahrenheit. The TH120 followed these temperatures practically to a tenth of a degree. I relocated the bator to a closet in the guest bedroom, minus the cardboard box surround. The ambient temps range from 66.2 degrees to 67.8 degrees Fahrenheit, and the bator temps are now relatively stable at 99.5, with an occasional drop to 99.0 for about an hour or so.
~Several weeks later~
I am disappointed in the TH120ıs performance. I had none of my twelve eggs hatch. I think the main problem was temperature instability. If the TH120 is in a location which fluctuates even a couple of degrees, the incubator will mirror this change. With the solid-state thermostat, it should sense when the temperature is too high and turn itself off, and likewise, sense when it is too cold and remain on for a longer period of time. This DID NOT HAPPEN. The light blinked on and off at the same rate whether too hot, too cold, or just right. Therefore, I had temps which were much, much too high and much, much too low and alternately toasted or froze the embryos. I had a recording thermometer on the outside of the incubator the temperature swings over a 24 hour period were between 6 and 8 degrees. Rather than adjust the incubator temperature (difficult) I tried to stabilize the environment I put a desk lamp in the closet with the incubator and turned it on when the outside temperature dropped, like at night. This did smooth out the temps somewhat, but I had only two eggs out of twelve that even developed embryos.
Another thing which may have added to the temperature fluctuation was the fact that I had so few eggs in the incubator. The bator is designed to hold 48, and I only had 12 (six, after I put six under a broodytoo late to even develop embryos they had already been toast). Eggs in the bator respond to temp fluctuations much more slowly than the air surrounding them, and a large number of them will hold a more steady temp than just a few. It might be worth it to try to put a few partially filled water balloons in the bator along with the eggs if you only have a few eggs to hatch. The water in the balloons should work as a heat reserve against temp flucuations.
On the candling wih it: When I took it out of the box and put it together I kinda scratched my head-bone and was wondering how in heck you candle with it...I tried it, but it really didn't work well. I tried first with light tinted eggs, and didn't see much. With the dark-shelled Marans eggs I needed a more focused light. I ended up using a smallish cardboard box with a hole cut out in it and put it on a 75 watt table lamp like a lampshade. That worked much better.
Conclusion? I really wanted to like this incubator, and still think itıs a good one IF and ONLY IF you have a location that will not change more than two degrees no matter what the weather. If I had known just how sensitive the TH120 is to temperature swings, I may not have purchased a Top Hatch but rather gone for a bator with more reliable insulation. Call me irrational, but I think an incubator should be able to handle a few degrees of temperature change over a 24 hour period. Brower may want to change its design a little if they made a Top Hatch with a double-walled construction (like your average insulated plastic coffee mugs) this bator would be outstanding.
