have a rheem heat pump. Have heat and have air. On an occassion it makes a clicking sound, like it's trying to turn something on or off. Fan works and I hear the compressor work. Clicking sound sometimes takes awhile and other times it starts right up when the heat pump begins. Does not seem to matter the temperture outside. So far, I have not heard it make the clicking sound when the air conditioning is in use in the summer.
Does anyone know what may be the cause?