Incubator temp ?

[Grego6610]

Hi.
I have had chickens for 3 years now but this is my first time I am trying to incubate. I am using a Brinsea octagon with automatic Turner.
From all that I have read a broody hen temp is 105 to 106F however everyone recommends optimal incubator temp. is 99.5F
Why such a significant variation ?

 

[Poultrybreeder]

The incubators are not as effective as a broody hen, and have to be kept at a lower heat so that if the temperature spikes, it has lower chances of affecting the chicks. Hens have extremely low, to no chances of spiking, so they have higher heating

 

[Grego6610]

And yet they will hatch under a bloody hen in 21 days.
I read a post which stated one should not completely believe the displayed temp. rather when the chicks hatch. If they hatch one day late, increase the themp. by 1 degree, if they hatch 1 day early, decrease temp. by 1 degree.

 

[Poultrybreeder]

Yeah, I rarely use an Incubator, because I never have any luck with them. But that is true, my inc said that it was 100 degrees F, I stuck another thermometer inside of it, that one said it was 110 degrees F! That is a great difference in temperatures

 

[Ridgerunner]

For a forced air incubator the recommendation is 99.5 F. For a still air incubator the recommendation is 101.5 F taken at the top of the eggs. In a still air (one without a fan) where you take the temperature matters.

Why do you use 99.5 in a forced air? Because it works. If you try to incubate the eggs at 105 or 106 you would cook the chicks inside. Just because a broody hen's internal temperature is that high doesn't mean she keeps the eggs that temperature. She can regulate the temperature of the eggs and does.

I never believe a thermometer until it's been calibrated. Many of them are incorrect. Sometime you are at a hardware store or at a big box store go to the thermometer shelf and check them out. I've seen as much as a 9 degree Fahrenheit difference in the high to low ones on the same shelf. The thermometers that come with the incubators and thermostat factory settings are no more reliable.

 

[Grego6610]

Thanks for all your help. What brand thermometer do you use to calibrate your setup ?

 

[Ridgerunner]

I don't know brand. I use an old-time medical thermometer that is already calibrated in the temperature range we are working. Put the two thermometers in a cup of water about 100 F and see what you see.