Hello!
I bought a home that was built in 1999 and it was vacant in the Phoenix heat for 9 months. We put in a new hot water heater in the garage and a ground mounted a/c unit on the side yard in July. It is now Dec and the heat is on at night. Would all those changes contribute to loud pops at night and ceiling cracks (lots in the garage, walls too) and some minor ceiling cracks inside the house (centrally located)?
Thanks for your help!
Jennifer

They weren't noticed before? Typically you tend to note cracks more in the winter as the humidity drop causes some shrinkage. Show us a picture of the cracks. Where are they located?