Incubator project.

[MeepBeep]

From what I've heard, using a reptile heat mat is extremely unlikely to overheat, I'm not sure what temperature it would reach if it did though, so I'll look into that.

I used to sell exotic animals for a living, I'm very experience in reptile heaters... I have seen many overheat and fail, I have even seen them smoke up and melt... Plus as I said they are designed to run at +20° over room temp, thus in your application they are likely not going to work unless your coop is always 80° or more, combined with the fact they are slow to heat and recover...

Also, reptile heating pads are usually placed directly under the terrarium, they have no issue being covered by it that I've ever seen or heard about. I could test what temperature they can keep a nesting box at at some point.

You described their use outside the tank on a sheet of glass not covered in combustible bedding, or worse a layer of combustible chicken dust and feathers... Go read the warnings, even the ones that do say you can cover with a 'thin' layer of bedding warn it could cause failure of the unit...

Do you have any alternative heating method which could be used?

Nothing that doesn't run a fire risk, beyond some type of hot water radiator or forced air system with the heat source outside the actual coop area...

Also your idea for a pressure plate is prone to fail as well, dust, poop, feathers or what not could cause it to get stuck on or off or not function properly...

BTW, I'm a freelance electronics engineer, I brain storm and design things like this for a living.. I'm not trying to flat out negate your ideas, I'm simply pointing out factual issues and concerns with the design...

 

[IncubatorDevice]

Thank you very much, your advice is being very useful. I see you're very experienced for this kind of project.

For the pressure plate, do you have any ideas on how to seal it against dust and the like? There would need to be a way of preventing dust falling down the edges of it.
I can think of a few solutions to the problem, a basic tray like structure could hold the plate, then have some kind of waterproof fabric over it so dust can't get in, yet the pressure plate can still be activated? You'll know better than me, do you have any solution?

I'll have a look into other ways of heating the device, thanks for the help!

 

[MeepBeep]

As said earlier forget the pressure plate, as alternatives like PIR motion sensors are dirt cheap... You can get an already built, PIR sensor board with a relay for about $3 delivered on Ebay from China...

That doesn't solve your heating issue though...

 

[ChickenCanoe]

I think the simplest and cheapest would be a thermostat. You could put the probe in the nesting material and set it for about 80-85F,
For a heat source, rather than an infrared heat lamp or something else, if I was going to do the project, I'd use a low wattage (50 or 75) ceramic heat emitter. Much more unlikely to start a fire if held securely a distance from bedding or flammable material. They are also more reliable than glass lamps.

 

[MeepBeep]

For a heat source, rather than an infrared heat lamp or something else, if I was going to do the project, I'd use a low wattage (50 or 75) ceramic heat emitter. Much more unlikely to start a fire if held securely a distance from bedding or flammable material. They are also more reliable than glass lamps.

Ceramic heat emitters generally run about 450°F or more on the surface, that is enough to cause spontaneous combustion of chicken dust... You compound the issue when you put that lamp in a small space like a nesting box...

Not, saying it will but the risk is very real, as evidenced by the number of barn and coop fires every year...

 

[IncubatorDevice]

Thanks, I'll have a look at some of those to buy, if I can work out a suitable heating method.

Have you ever had any experience with these types of heaters?
Coil heater
Cartridge heating element

 

[ChickenCanoe]

Yes, I have both in an incubator/hatcher. However, they're intended for an enclosed, insulated container. not a coop nest box.

 

[MeepBeep]

The coil heaters is basically what you see inside your toaster, full blast they will be a glowing red hot fire starter... You can control the amount of heat they generate by controlling the electricity into them, but you end up with the problem I touched upon earlier, that is the recovery time... If you dial it down to a safe temp, it won't be able to recover the temp in the nesting box or maintain it properly...

The cartridge heater, can get up to about 1250ºF, again you can limit the output by limiting the input, but you end up with the recovery dilemma again...

 

[IncubatorDevice]

Do you have any ideas on how to recover and keep the correct temperature in the nesting box, safely?

 

[MeepBeep]

As I stated earlier, forced air heat from an external source or radiated heat form an external boiler... This puts the heat source outside the coop but still allows brute force heating at bellow combustion temps in the coop itself... This is why both the above methods are generally used to heat houses, with the exception of the heat source being located outside in most cases, they work well and drastically reduce fire potentials...