Temperature spiked 2 degrees in the night why?

[Sphynxcrazy]

turned the eggs last night like normal and added water. Temp was 100. It usually stays 100 but sometimes on cold mornings it is 99. It was 102 this morning. I turned it down and watched it cycle a few time to make sure it was steady.

The one thing I did last night was I turned the lid one turn so it would be safe so no one pulls the plug. I also moved the thermometer to where the window was.

it is a hova-bator turbo fan. I turn eggs manually.

I can not see how turning the lid could affect it since it's forced air so...??? Could it be because their growing making heat? They will be in there a week at 5:00.

I really hope that the spike didn't hurt them. I wentnto bed around 12:30-1:00 and got up 8:30 so they werentnin temps to long, depending when it spiked. These will be my first hatch! ( it's just so amazing that you can look at these eggs and see something growing!!

 

[Hangtown Farms]

Mine does that sometimes. not really sure why. as long as it stops at 101 and then hits 102 for a few seconds it should be ok. more than that I am not sure.
My last hatch was 6 out of 18 of my own eggs and it was doing this during the day from time to time. is it ranging ? 98 to 102 or staying at 101 102.
mine seems to range

 

[Sphynxcrazy]

Now, did most eggs form or start to form or what did they do?

 

[Hangtown Farms]

sometimes as the chicks gain mass they make more heat. not sure if that would of done it though

 

[Sphynxcrazy]

Okay since today's was day 7 I candles. I had an 18 pack that was meant for hatching, and I threw in 4 eating eggs that were in the fridge. The lady has a rooster, and I believe 3 of them are forming

5 of the 18 were duds. All RIR/leghorn cross. Those were the ones I was wanting to hatch. I couldn't tell very well on the welsummers, and some darkvbrown eggs so... Out of 22 6 duds.

I have one egg that I had in my homemade bator I was testing and it started forming! I threw it in this bator, so I don't know what will go on with it, so I'm not counting it.