Temperature Levels on Forced Air Home made bator...

[galluskid]

Hi Guys,

I just finished building a drawer type incubator... I have 2 drawer trays, top drawer temp from 100-102, bottom drawer temp from 98-100... It's a forced air design but it seems no matter how many times I check, the bottom drawer doesn't get as much heat as the top one...

I am using just 1 PC fan now and considering putting 2 fans to maximize the "push" of the hot air to the lower level, if successful, I can then lower the temp 1* more to hit the 99-101 range I am looking for...

What you guys think? Is this viable? Anybody had the same problem and solved it? Need some help on this...

Thanks...

Edited to add photo:

This is the incubator when I haven't installed the viewing glass yet and made holes for the "push and pull" tray for egg turning...

 

[bigdawg]

very nice. not sure how to help. your temps are with in range. my homemade cabint type has a big fan in the top, heat strip in front of it, and it has a false wall in the back, so that the air pulls from the bottom and blows out the top. circulates the air through out the bator. you may need to install a false wall in the back, add another pc fan so the air will circulate throught out the bator. my hatching trey is at the bottom. the false wall is about 4 inches off the bottom. it also has a vent hole for fresh air on the back side. i would post pics but i havent figured out how. hope i could help.

 

[galluskid]

bigdawg,

thanks... well I just installed a 2nd PC fan and it seems to solve the issue and makes the top and bottom tray temperature almost the same (99.1 - 101.3, hi and low reading for both trays)... but... one of the fan has become "slower" than the other and now the side of the bator with the slower fan has a higher reading while the side with the faster fan is just about right... I doubted it a bit so I switched the fans and true enough I got the same result...

all I need to do is get a new fan running the same speed as the other fan and everything will be set...

I do have the bottom most part of the incubator (where I put the water tray) at a low temp (96.8), will try to set it again once I get a new PC fan...

 

[Penturner]

Heat rises, put one or two computer fans on the ceiling above the top drawer to push the warmer air down. if computer fan does not provide enough draft to push the air all the way down to the bottom drawer. As far as testing for your air flow you might want to try and find some smoke capsules. they use them to test smoke detectors. and you can actually watch the smoke travel on the air streams of the bator. makes it a little easier to position fans than just guessing at it. Another tip that comes from my experience with trying to get even circulation. I have found the best basic set up would be two fans, one in each back corner angles slightly down and angled across the corner at 45 degrees. In effect this creates a figure 8 air flow. you can still end up with some dead spots but not as many as with other set ups. the idea is that the fan at the left back upper corner is aimed at the right front lower corner and the fan in the right back upper corner is aimed at the left front lower corner. the worst dead spot is then at the center back low. this is the best location for your heat source. thermostat placement is not critical since it will be adjusted once all the other elements are in place. thus compensating for how they all function together.

 

[galluskid]

Penturner,

Thanks for the ideas... Anyway this is the section of the bator I made, if you notice, I put some angles on the top back and front portion of the bator to help in the air flow...

Seems to work good enough at the moment for the top two trays, if the 2 PC fans will not work to push the hot air up to the bottom, I may consider changing the PC fans into one of those "Evaporator Fans" (used in the fridges) which I know having stronger air flow and are AC powered which in actuality is better as I can remove the DC adaptor I am using for the PC fans, which can get very very warm once running a few days continually. Actually I am considering using one even if the PC fans will work...