Any type of HVAC damper actuator can be configured as a coop door opener.
This Youtube video walks you through the steps and wiring details.
Using a heavy duty actuator like this closes the coop door with enough force to prevent any raccoon or monkey from pushing it up.
One of the nice things about converting a PetSafe electronic pet feeder into a chicken coop door opener and closer is the fact that it has a built in timer to control your opening and closing time.
You’ll need a small structure with a pulley mounted like in the picture and some heavy duty string or fishing line.
The door should be light and travel freely in an up and down motion.
The power cord on our EcoGlow chick brooder broke at the nub.
I’m pretty sure the reason it broke was the way we wedged the brooder power cord up against the wall of a plastic tub. I don’t think it was meant to bend at such an extreme angle with pressure.
I used a coping saw with a knife to free the nub from the plastic case. There’s not much wire to work with, so make sure when you cut it that it doesn’t fall back in the hole.