We’ve tried 3 different types
of mechanical timers for the supplemental
chicken coop light and
all three have had issues of not working right during temperatures that
get close to freezing.
One solution might be to
build a little insulated box to put it in, but it still might get too
cold inside.
The above digital timer is
easy to program and has not failed even once since we’ve installed it.
It will cost 2 to 3 times what a mechanical timer can be found for, but
is well worth it if your chicken’s circadian rhythm stays intact.