Made a full sized refrigerator into an incubator in 2 minutes!

[Scales Zoo]

Yes, 2 minutes!

Our main incubator is out on loan, I have my first one (a hovabator) here incubating lizard eggs - and I was going to build a fridge incubator with my spare hovabator thermostat.

Except I don't have a spare hovabator thermostat - or atleast I couldn't find it.

Anyways, yesterday it looked like one of the pythons might be getting ready to lay - so I new I had to act quick. My plan was to rob the thermostat from the hovabator - and spend a day making a really nice incubator out of a fridge, fan, thermostat and heat tape.

Then I realized, the hovabator lid has a thermostat, a heating element and a fan. It also fit, upside down, into the bottom of the fridge quite nicely. The cord fits through the door.

It holds the temperature right now to .4 degrees F. I'm going to fill some tubs with moist vermiculite, and see how much variation there is between racks (hot air rises). I do have a small fan that is read to go in there and be on all of the time if need be, but at this point I'm guessing it won't be needed.

So, any of you needing more room than your hovabator - get nonworking fridge and give this a shot. (I had originally built my other incubator so I could remove the "guts" and put them into a fridge) Most people are happy to give you their non working fridge, just to get rid of it.

I may drill a small hole into the side of the fridge - but I expect to be opening it a couple of times a week - so I am not sure if a small hole is needed.

Ryan

[crocdoc]

Fridges make excellent incubators, in my opinion, based on my limited experience with them. I'd skip putting the hole into the fridge, though, as it'll just take away from the effectiveness of the insulation. If you drill a hole in the back to accomodate the cord that runs to the hovabator components, that should be enough, for you'll get enough air exchange opening and closing the door when you peek at the eggs. If you're anything like me, that is, for I peek at my ^&%$* eggs way way too often (I'm too impatient and picked a species with a 240 day incubation).

Be careful with the fan, too. Depending on the type of fan, size of the fridge and efficiency of its insulation, even a small fan can generate enough heat of its own to throw out your steady heat settings. I found this to be the case with a computer fan in a converted bar fridge.

[BoidKeeper]

Pics!
I'm thinking of doing the same thing.
Cheers,
Trevor

[Classic]

We retired a portable dish washer today that is going to be converted into a new incubator also.

Brian

[Scales Zoo]

Originally posted by BoidKeeper
Pics!

I would have taken pictures, but I am still cameraless, since my camera was stolen.

[Invictus]

Sounds awesome Ryan. I'm looking around for a nonworking fridge for this purpose. Shouldn't be too hard, people usually give them away. JUst a thought though... why not run the heat tape right up the back, from top to bottom? That way every single rack gets the same exposure. I think that's what I'll be doing... plus a small computer fan on each rack.

[Scales Zoo]

I've always tried to avoid radiant heat in incubators. I'd been warned about that from Roy, but found out with my own experimenting that it can cause overshoots in temperatures (inside the egg box, where the temperature matters)

The air temp in the fridge, now, is 89.2-89.6, in the vertical center. I've yet to test the low and high ends. I'd guess the very top might have more of a fluctuation - but I will test that.

I expect the temperature inside the closed rubbermades (with moist vermiculite) will not fluctuate as much as the air temperature, because of the inherint capacitance it would add to the system as a whole.

I may not need to use a fan, (ther is a turbo fan which comes on when the heat element comes on) but if I did, I'll only use 1, aimed upwards to keep the air circulated from top to bottom, and keep it on all the time.

Since the fridge is such a closed system, and well insulated - the always on fan would work similar to a convection oven - but convection is only an advantage (in my opinion) if one is trying to raise the temperature, or cook a turkey.

If the temp of the egg boxes and the air is all 89 - it will tend to stay at 89 (inside the egg containers, where the temperature is important) - that is my theory anyway, I hope to find my vermiculite and test it today (damn spring cleaning - can't find anything!)

Ryan

[Piers]

Well Ryan I'd say it was more like 5 minute to do mine (had to drink beer to keep hydrated hehe). Any way we used flexwatt and a old helex thermostat and though we need to get a fan the temp at the middle rack is 89.1 and has been that since yesterday.
Thanks Ryan for the great idea.
Piers

[Scales Zoo]

Just a follow up.

We got eggs (Elvira's 40 eggs on the giant python forum), and I put them into 2 rubbermaids. One is tall, the other is the standard large short one.

Air flow was restricted because the tubs are nearly the size of the fridge. I added a small fan (kept on all the time) to help circulat the air, but I still had about 1.5 F difference between the top and bottom tub.

It is actually the bottom tub that is warmer, because my heat element is at the bottom (i had thought the top one may be warmer, since hot air rises) The leftover radiant heat affects the bottom one, even after putting some cardboard under it with the hopes of insulating it from any direct heat.

I have one of those HCS systems that Grant VG sells, and decided to set it up and test it out. I have a peice of heat tape at the top of the fridge, and am regulating it to keep the top part of the fridge at 90 F. Both egg containers are now within .4 degrees of each other, one is 89, one is 89.4.

The HCS is a 4 probe unit, and this morning we had northern pine eggs. I put the eggs inside a rubbermade container in the freezer part of the stand up fridge. I used a normal human heating pad propped along the back, and set the HCS at 83 F. Currently the eggs are stablized at 82.5 F, and the HCS is keeping the ambient air right at 83 where I set it.

[Scales Zoo]

Oh yeah, and I did drill a hole into the side of the fridge.

Was talking to Don P. and he asked if the fridge had a hole, because without one, sealed up like that, when closing the fridge the pressure can spike inside of the fridge (because it is sealed). He never actually said it would harm the eggs, but I wasn't about to take a chance that it wouldn't.

[Lisa]

I have an old fridge that i'm planning on doing this with except i'm planning on filling the crispers with pop bottles to act as a heat sink

I also plan on having the fridge repaired so i can use it to brumate so drilling holes isn't in the plans... i'll probably put in a powerbar so that i can support a few things such as light rope so the web camera can see and minimize the wires coming out of the fridge.

[WingedWolf]

1.5 F difference? That is a bit of a quibble, isn't it? I mean, most eggs are going to have a lot more tolerance than that....
Perhaps expecting more is a bit anal? I'd be ecstatic with that little of a variation. My water/cooler incubator this year has NOT held anywhere close to steady.

;)