sjturner79
Songster
I've never heard of a cold brooder. If you can get the incumbator stable enough to hatch the eggs then use an oversized brooder with a thermostat and keep it in one of the cooler rooms of the house.
If it doesn't get over 37c then you can use heat overnight or when it's below 30c for the first week and leave them heat free.
I get outdoor temperatures in the 40s in summer so I let the heavy birds and chicks use the laundry to cool off. My silkies and frizzles don't seem to mind the hot as much