Noisy equipment, excessive humidity within the home and a unit older than 10 years are among the top reasons to replace your central air conditioning, according to Energy Star, a U.S. government program promoting energy efficiency.ost central air conditioning units come with two-to five-year warranties. Extended warranties can be purchased for an additional price -- usually for several hundred dollars -- and the longer the warranty, the higher the price.
The following are prognostic factors for advanced and metastatic nonâsmall cell lung cancer: 1  number of metastatic sites People with a single metastatic site have a more favourable prognosis than people who have cancer spread to several different sites.
When tumor cells metastasize, the new tumor is called a secondary or metastatic tumor, and its cells are similar to those in the original or primary tumor. This means that if breast cancer metastasizes to the lungs, the secondary tumor is made up of abnormal breast cells, not of abnormal lung cells.