Red Tail escaped...need some help

[Remedy99]

Hi, Im new to the forums. Just yesterday my Red Tail pulled a houdini and escaped from his tank. I searched any possible spot but just cant find him im guessing maybe he went into the walls? someone told me to leave the air conditioners on in my house and that the walls would get too cold and hed come out looking for heat....i dont if this is true maybe someoen can confirm that. Hes about 3.5 feet long and hes very docile yet also very shy, he also just ate 3 small rats a couple days prior to this. If anyone has any tips for getting him out its greatly appreciated!