Don't quite understand how fresh air enters incubator

[bigoledude]

I will have 3 fans circulating inside my incubator that I am making from a small cabinet. The way I see it, because the inside is enclosed, there is neither a positive pressure nor a slight vacuum inside. Just circulating what air is inside. What makes the air enter through the holes everyone puts in the walls of their incubators? It seems that it would take large holes to accomplish total volume replacement every hour or so? Is anyone monitoring O2 readings inside?

 

[Sweetlilbaby]

I have forgot to remove the little plugs in an incubator before and it caused nothing to hatch. The next time (eggs from same hens) Everything was done the same except I remembered to open the vents on the incubator and I had all but 2 eggs hatch. Both times I had 24 eggs in the incubator. So yes those tiny holes make a huge difference. You don't need all the air replaced in the incubator, The chicks aren't going to breath all that air in at one time or anything. It needs a slight air flow to replace the air.

 

[bigoledude]

The cabinet is about the size of a small bathroom vanity. How many and what sized holes would seem best?

 

[Hawgon]

The cabinet is about the size of a small bathroom vanity. How many and what sized holes would seem best?

Awaiting a reply also, I am at that point in the building of my incubator from a mini-fridge....Location of holes would be nice also, I read on here holes on the bottom on one side and on top on the other to get some "cross-flow" action...

 

[Hawgon]

Bigoledude-I put several smaller holes in my fride-abator. Trying to find some cheap test eggs now. I will let you know how it all works out.

 

[Sweetlilbaby]

My home made incubator has 1 hole in the bottom on one side, and mid way up on the other side. Everyone does them a little different though. I think the most important thing is that there is some ventilation not really where it is at.
I do holes the size that store bought incubators have (for me it's about the size where my pinky only fits the tip in it). But once again each person will have a different opinion of what size it should be.

 

[bigoledude]

I just wonder sometimes if some of our poor hatches are due to low oxygen levels in the incubators? I am gonna scrounge around for some old O2 analyzers at the refinery near here. I'll ask some old chicken wranglers around here to check their O2s along with me and see what we come up with.

 

[cva34]

I would put a 2 in top or near and 2 in bottem or near .About 1" holes .The air is exchanged by heat riseing and going out and replacement air going in bottem to replace it and of course some is helped on its way by fan air movement.You can always close off with duct or set something over hole if need be..cva34