Quote Originally Posted by Malum Argenteum View Post
Broken record warning: I would (and did, and do) use a Herpstat. Here's why, for incubators. (A) they are dimming thermostats, which means they're not just on or off, they ramp up power until temp is reached, and then apply a percentage of the power to hold the temp there. The variance in my incubator run by a Herpstat is 0.3F -- set at 80.5F, it holds from 80.4 to 80.6. Is that necessary? I don't know, but I do know that the huge swings a Hovabator is prone to aren't great (daily cycles in temp have been asserted to be beneficial to incubating eggs -- that's a more European-based technique that may or may not be practiced anymore, I don't know -- but a night drop is different than random and frequent variance).

This is related to reason (B): Herpstats (well, the H4, anyway) have a maximum power feature, where you can set the stat to only apply up to a max percentage of power to the heating element. This is very important in the overpowered Hovabators, since a simple on/off stat will run full power up to the set temp, and then as the heating element cools after power is cut it will continue the upward arc of temperature, maxing out a couple degrees above the setpoint. Limiting power to, say, 40% or 50% reduces that temp overshoot (better designs, like those that use heat tape, don't have a big problem with this since heat tape doesn't retain heat the way those rigid resistive elements do).

The H4 has four channels, so the others can be used for other heating/cooling/lighting/humidity devices.

There's also the alarm that'll let you know when the temp isn't rising when the heat is on, as when the incubator has been left open -- another useful feature.
That's ^ ^ ^ a great explanation & awfully convincing!