ruthhope
Free Ranging
I keep my little fluffies and their brooder in the house as it is easier to keep them warm.48° is the overnight low. I don't really have a thermometer except a probe type for in an oven.
ELectricity and heaters in the coop with all that straw is a fire hazzard.
I also think you need to urgently invest in a thermometer to check the temperature in the brooder.
Any chance you can bring them into the house for a couple of weeks?