They need the light out at night, that may be why she is sleeping during the day. Please fill out the form. If your house drops into the 50's then you can get a ceramic heater that does not produce light. If your house is 60 or above it is not necessary. Chameleons benefit from temp drop at night.
if it only gets down to 70 then you don't need any heat. If you notice your chameleon sleeping duuring the day in her cage then something is wrong. they do not sleep during the day, only at night.