How to lower temperature of homemade incubator?

[alpinewelsummer]

Hey all! I'm working on a diy incubator but I've ran into a small issue; no matter what bulb I use (I've tried 40 watts all the way up to 60 watts), the temperature goes to 110 F. I've tested with a mercury and a digital thermometer so I know it's an accurate reading. The temperature also holds steady and reads evenly no matter where in the incubator the thermometers are placed, so that's not a problem.

I do have a small vent hole for the fan to let fresh air in--do you think I could drop the temperature to the appropriate 99.5 degrees by widening this vent slightly? Any other suggestions?

The incubator is a modified old mini fridge with a bulb and a fan installed into it, if that makes any difference.

 

[jher77]

I do have a small vent hole for the fan to let fresh air in

Don't put the vent hole where the fan itself will pull fresh air in directly. Vent should be installed in off-kilter way.

What kind of thermostat are you using? You say temp holds steady, just lower the thermostat temp. If you are thinking of just using a certain wattage bulb and then adjusting the vent size to control the temp, that isn't going to work. You need good thermostat, because if room temp and humidity changes, the temp inside the incubator will go haywire.

Got pictures?

 

[Mellowmalt]

jher he isn't using a thermostat by the sounds of things.

It is possible to do it without a thermomstat but jeez I would not want to try.

So a possible way that might work is to get a fan speed controller or a light dimmer. They should be about 8 dollars or so.
You then plug your 40 watt light into the fan speed controller and turn the dial down.

If the incubator is sufficiently insulated then it should roughly be able to hold temperatures without having to adjust itself, the problem is most homes change temperature throughout a month and as temps change in the house day and night so must the temperature be adjusted manually in the incubator.

I've seen it done and generally it works better in places that are hot already. Like 30 C ambient temp, then you would just need to raise temps by 7 degrees to achieve incubation.

 

[alpinewelsummer]

Soooo basically: more purchases needed. Thank you both for the info.

 

[Mellowmalt]

I use this one. It might not be calibrated correctly (they rarely are - always use a calibrated thermometer to check) but it can maintain temps very steady, can be adjusted by 0.1 degrees and isn't too expensive

https://www.amazon.com/Reptile-Terr...+thermostat+controller&qid=1619252464&sr=8-25

 

[alpinewelsummer]

I use this one. It might not be calibrated correctly (they rarely are - always use a calibrated thermometer to check) but it can maintain temps very steady, can be adjusted by 0.1 degrees and isn't too expensive

https://www.amazon.com/Reptile-Terr...+thermostat+controller&qid=1619252464&sr=8-25

That's perfect! I was expecting something far more expensive: thank you so much!

 

[Mellowmalt]

You can also try a lower powered heat bulb. The thermostat I would recommend 100% anyway but if the heat bulb is too powerful it will be constantly switching on and off which will reduce the lifespan of the bulb so you can always use a lowered powered bulb that produces less heat so will switch off less often.

you can get 15 watt and 25 watt bulbs:

https://www.amazon.co.uk/Exo-Terra-...&keywords=25w+heat+bulb&qid=1619255754&sr=8-5

 

[alpinewelsummer]

You can also try a lower powered heat bulb. The thermostat I would recommend 100% anyway but if the heat bulb is too powerful it will be constantly switching on and off which will reduce the lifespan of the bulb so you can always use a lowered powered bulb that produces less heat so will switch off less often.

you can get 15 watt and 25 watt bulbs:

https://www.amazon.co.uk/Exo-Terra-...&keywords=25w+heat+bulb&qid=1619255754&sr=8-5

That's a good idea too. I'm on a 40 watt, so maybe a drop to 30/35 watts will get things closer to the 99 mark.

 

[Kiraeh]

A thermostat would give you peace of mind but you can do it manually- I had a good hatch with a dimmer switch, but I had a thermometer with an alarm and am a light sleeper.
You should have more than one small ventilation hole, but whatever mechanism you use to adjust the temperature should be something else. I finessed the dimmer switch with a piece of Styrofoam over the viewing window on the top of my coolerbator.