By Alan Stanford - based on Hoverbator incubators, a common make in the country this aricle was written. Check the links directory on this website for other sites selling various makes / models of incubator

 

As to incubators, sometimes you can have 100% hatches and sometimes nothing hatches. I highly recommend the forced air models. An egg turner is convenient but not necessary, you can do very well turning eggs by hand twice a day.

Forced air is the only way to go; it gives a uniform temperature inside the incubator. The fan should be on all the time not just when the heat is on.

Wafer thermostats change set point when the atmospheric pressure changes. I strongly recommend electronic temperature control.

Water (and I assume electronic) thermostats change set point when the room they are in changes temperature.

Where to Put the Incubator

It is important to put your incubator is a place where the temperature and humidity are constant and there is no breeze. The temperature controllers will not work in rooms where the temperature changes.

Temperature

The temperature should be 99.5 degrees Fahrenheit for chicken eggs.

You must measure the temperature, but no matter which thermometer you use, adjust the temperature according to when the chicks hatch. Chicks are the best indicators of temperature. Increase the temperature if they hatch late, decrease if early.

Do not adjust the temperature if the humidity is wrong. The thermostat keeps a different temperature when the humidity changes. This means you must watch the temperature after you increase the humidity 3 days before hatch.

We use the small GQF electronic egg thermometer. It is accurate to +/-0.18 Fahrenheit degrees. Many larger digital thermometers and thermometers / hydrometers are only accurate to +/-1.8 Fahrenheit degrees. Since this is exactly a factor of ten and catalogs are printed on newsprint, you have to read the catalog very carefully. We like the larger thermometer/hydrometer for measuring humidity.

Another benefit of the GQF digital thermometer is it responds quickly to temperature changes. To control a Hovabator we averaged the minimum temperature (when the heat turns on) and the maximum temperature (when the heat turns off). The thermometer/hydrometer takes tens of minutes to settle to the inside temperature. Make sure you place the probe of the thermometer at the height of an egg's top.

Humidity

The humidity should be 50% days 0-18 and 65% days 19-21.

You must measure the humidity. I like the inexpensive combination humidity and temperature gauges one can buy at most hardware stores. Do not use this device for measuring temperature! It is very inaccurate and responds too slowly to changes in temperature.

High humidity prevents moisture from leaving eggs and the chicks drown. Low humidity at hatching gives stuck chicks and chicks that don't hatch at all. The membrane inside the shell gets tough and the chicks can't poke through. Even if they pip, many stick to the membrane and either can't get out or get deformed feet, beaks, and I assume other parts too.

Many people call the last three days of incubation "Hands-Off Days". These days are most important to the hatch. Opening the incubator quickly drops both the temperature and the humidity. Nathalie suggests putting an aquarium tube through the incubator vent into the water troughs. Then you can add water without opening the incubator.

Time to Hatch

Chicken eggs take 21 days from the time they are put in the incubator. Do not start counting days from when the eggs are laid. Do not start opening eggs until 2 or 3 days after they are due. Wait even if most of your eggs hatched. If the temperature is low or if that unhatched egg was in a cooler spot of the incubator, that egg might just hatch late.

Cleanliness Is Most Important

We were happily hatching with our incubator with me adjusting the temperature twice a day. Then the foam surround got bacteria in it. I always scrubbed the foam and submerged it in bleach solution for an hour. To clear up the infection, I soaked in bleach solution for 24 hours and left it in direct sun for a day.

Humididty controls, thermometers and other accessories like mentioned above can be found here