Pulling my hair out over my incubator.

[Sakai]

Newbie hatcher here. Our first round of hatching went bad and we believe the humidity was far too high so we tossed the cheap tiny incubator for a homemade one. It's much larger but we seem to be having issues.
I've been posting my troubles with this incubator in the August-hatch-a-long, and I'm feeling bad for them having to deal with this newbie.
I'm sure I've ironed out all the kinks except for one.
We have the incubator in a bathroom where there are no windows and the AC vents are closed. We are also using a heat sync in the form of a bottle of water.
When we raise the humidity (To test for lockdown) the temp drops. I assume this is because heating the moisture in the air takes extra energy. The temp will go from 99F to 97F and sometimes overnight will drop to 95F. This is frustrating because I always assumed there would be a temp drop at first but in a few hours would rise, not continue to fall.
Efforts to cover the bator (with a towel or blanket) causes the bator to spike up as high as 108. @.@
So my question is...is this slow decrease in temp going to harm the eggs? I assume it would cause them to hatch late but would it kill them? I know a temp spike of any amount will kill them, but will being at 97 for a few hours or even 95, harm them? It would only be for a few days as again, this only seems to happen once the humidity hits over 45-50%.
Should I hold off on hatching until we can get the incubator to hold steady?
Should I be prepared to wake in the middle of my sleep and come home on my lunch hour to check the bator?

 

[RubyNala97]

Does this happen when you add any humidity or just when you add a lot of humidity for lockdown? What is your humidity % without any added water? Depending on the type of eggs you are hatching you might not need to add much water for days 1-18. As for during lockdown, it’s ok to have lower temps during lockdown. The eggs don’t need it to be as hot when they are about to hatch. You wouldn’t want the temps to be constantly fluctuating during the first 18 days, as not only would the lower temps delay hatch but it can also cause developmental problems. BUT if it’s only for hatch time it may be fine. You could monitor the eggs and only add water when you see they have internally pipped. The 95-99 temp
Should be fine for them during hatch time but not for the first half of incubation. But again depending on what your humidity is without water and what kind of eggs you are hatching you might not need much more humidity during the beginning. Does that make sense?

 

[Sakai]

Yes, this only happens when the humidity gets above 50%.
Without water with the weather, we're having the humidity sits between 20-40% and the temp is rock steady.
We're hatching chicken eggs.
But this makes me feel better. The temp only swings when the humidity is at lockdown levels I think I will do as you suggest and only add humidity as they start to pip inside. I have a system to let me add water without having to open the bator. So there's that for an emergency.
Also, my man went and ordered a thermostat to shut the light on and off to help regulate the temp. I'll be adding this before we start setting eggs.
Thank you for easing my mind. ^.^

 

[Sara L]

What temp was the water you added? That can make a difference as if it was cold or room temperature water then it would take a while to heat up. Try adding water warmed to right around 100 degrees, that should help prevent temp swings.

 

[RosieR]

A thermostat will 100% help you out with this.
You’ll probably find that once you add eggs your temp will fluctuate a bit more than when the incubator was empty. More mass holding heat and eggs produce a small amount of heat as well.

 

[Sakai]

What temp was the water you added? That can make a difference as if it was cold or room temperature water then it would take a while to heat up. Try adding water warmed to right around 100 degrees, that should help prevent temp swings.

We add hot water. Not boiling or anything, just hot water from the tap.
The first time we added water it was cold and we learned our lesson. But the temp still drops when we use hot, just not as badly. I expect there to be a temp drop but the temp never recovers on its own.
Perhaps I need a stronger bulb? I'm using a 40watt Maybe I should switch to a 60 watt. but I'm unsure if it would be overkill and then get too hot. But this thermostats we're getting should help.

 

[Sara L]

We add hot water. Not boiling or anything, just hot water from the tap.
The first time we added water it was cold and we learned our lesson. But the temp still drops when we use hot, just not as badly. I expect there to be a temp drop but the temp never recovers on its own.
Perhaps I need a stronger bulb? I'm using a 40watt Maybe I should switch to a 60 watt. but I'm unsure if it would be overkill and then get too hot. But this thermostats we're getting should help.

Unfortunately with a DIY incubator you kind of just have to keep making small changes until you find what works best for you. My DIY incubators have two 40 watt appliance light bulbs with a computer fan mounted in between. Do you have one light bulb or two, and is yours forced air or still?

 

[RubyNala97]

What breed of chicken eggs will you be hatching?

 

[Sakai]

Unfortunately with a DIY incubator you kind of just have to keep making small changes until you find what works best for you. My DIY incubators have two 40 watt appliance light bulbs with a computer fan mounted in between. Do you have one light bulb or two, and is yours forced air or still?

We have one 40 watt and it's forced air.

What breed of chicken eggs will you be hatching?

They are RIR and Wyandotte crosses

 

[lazy gardener]

Do you have a good thermometer that you have calibrated yourself against a good medical grade digital or bulb style thermometer? How many vents, where are they located, and did you do the salt test on your hygrometer.

IMO it's absolutely IMPOSSIBLE to hatch eggs without a thermostat. (Yes, some people get lucky, but they spend a LOT of time babysitting the bator, and the failures outnumber the successes.)

Please, before proceeding further, read all of "Hatching Eggs 101" in the learning center.