How long should my HVAC system last? February 24, 2011 â Art Avent, hvac advice. Among manufacturers, you are unlikeley to find anything definitive in writing on this question, but my personal opinion is that an electric heat pump & air conditioner SHOULD last 12-15 years & a gas furnace SHOULD last 15-20 years or more. Truth is, they last anywhere between 1 â 20 years.
Otherwise you may be asked to change your clothes and wear a hospital gown. It is best to leave all valuables at home. You may be asked to remove any jewelry, dentures, glasses, or any metal objects that may interfere with the CT scan.
You will be given earplugs or headphones to wear. It is very important that you keep as still as possible during your MRI scan. The scan will last between 15 and 90 minutes, depending on the size of the area being scanned and how many images are taken. Read more about how an MRI scan is performed.