This weekend we got the craigslist wine cooler into shape as a cabinet incubator.
After reading as much as possible, and studying other home-built versions, we decided to try mounting the heat/fan unit near the bottom. The interior of the cooler has a bump-out down low that houses the compressor, making it too narrow inside for a full shelf. Keeping in mind that heat rises, we also installed a speed-controllable computer fan near the top, hoping to maintain a steady flow of warm air.
What we didn’t realize is that the Incukit is really geared toward top-mounting, with the integral fan blowing back into the heating elements, pushing air outward. If it is mounted on the ceiling, this means air is not blowing directly downward onto the eggs. Warm air is pushed out at the sides of the unit, flowing downward, then presumably rising gently up, as warm air does.
With the current installation, air flow quickly became an issue. The side of the heater pointing up pushes too much warm air directly under the egg turner. This didn’t become evident until we loaded the turner, causing a ‘traffic jam’ of hot air and making the temperature go sky high. We quickly adjusted the Incukit settings, and eventually used a flexible poly cutting board as a baffle tucked at the back of the lower shelf to direct the rising air to the sides of the incubator. It’s not perfect, since as the turner moves back & forth, air currents change enough to bring the temperature up slightly until it moves again. It hasn’t gotten critically hot, and seems to hold for the most part right between 99.5-100F depending on the sensor. Which is another monitoring problem. The Incukit has an advanced thermometer regulating the thermostat, but we always keep back up sensors in the incubator to check for hot/cold spots or in case of malfunctions. Each of the 7 thermometers we’ve tried reads slightly (or more than slightly) different, even placed in nearly the same spot.
So while things have settled into a good temperature range, all that will change when it’s time to replace the egg turner with hatching baskets. Air will be flowing quite differently, and we’ll have to act fast to get settings and modifications figured out for lockdown. Once this test batch is done (or undone as we’ll find out at first candling this weekend), it seems the better course to move the heater to where it is designed to work best. I really like having the existing overhead light hardwired, and may replace it with an LED light I can mount near the top.