Trialing an analog tech upgrade to the coldframe. This spring loaded arm has a hydraulic piston that expands and contracts with temperature, opening the cold frame lid when things get too hot. A common bit of kit in greenhouses, but looks like it may work out here.
Amazon link.
@Tay0 No power, thermal expansion! There are a number of brands and styles, but I settled on this one
https://www.amazon.com/gp/product/B07P8ZT9MC/
Amazon link.
@rho now that's very cool. I love powerless solutions like that.
Amazon link.
@Tay0 Same. Its nice to have something out there that just does its thing without having to worry about power, or a sensor or micro-controller failing.
@rho aquire
@rho From where did you squire the piston? 12VDC?