When mine were that age.......it was still too cool for them to be outside in the run............but too crowded in the back
bedroom, where they'd been for a couple weeks.
So, out to the coop they went, with an infrared light on 24/7..........they could get under it if they needed, or get away from it
if they needed.
Until the weather broke, they were actually 'in' the coop for 6 days straight...........
When they were finally let out, how they loved being outside!
And since that day, they just put themselves in the coop at dusk! Worked like a charm!
I left a small wattage, florescent, red "party bulb" on in the coop........just to attract them back in when it started to get dark.
(It did look so cozy, with the red glow shining from the windows, and pop-door, at dusk..............if I were a chicken.....that would be where I would head!!)
I'm thinkin' that leaving them in the coop for a few days should work for your chickies as well!
If it's too warm, I'd be sure to have plenty of ventilation, leave the windows open and perhaps have a fan running for them.............their feeder and plenty of cool water............some mealworms to search for, or let some of those little
live crickets (that they sell in pet stores, for reptiles) loose in the coop, and stand back and watch the fun!!!
When mine are big enough to free-range, I believe all their time now spent in the 'run' will make them want to return to 'it' each evening,
just like all their time in the 'coop' made them want to return 'there'.
Have fun!!
Everything will work out fine!