Uncooked rice often contains the bacteria Bacillus cereus. These bacteria can form protective spores that survive the cooking process and if the rice is cooled slowly (and left between 5 Â°C and 60 Â°C for a long time), these bacteria spores can germinate, grow and produce a toxin (poison) that causes vomiting.
Obviously the colder a climate is, the more a furnace is required to run, and the shorter its life expectancy. With our relatively mild climate here in Seattle and the rest of the Puget Sound, the average life expectancy for a gas furnace is 15 to 20 years if well maintained, properly installed, and properly sized.
Each of these furnace components has its own maintenance requirements and life span. So, to answer the question of what is the life span of a furnace, one must define what the furnace is.Typically, the heat exchanger is the component which defines a furnace.In older furnaces, the heat exchanger was good for about up to 15 years, with a high-end expectancy of 20 years if regular maintenance was performed.ach of these furnace components has its own maintenance requirements and life span. So, to answer the question of what is the life span of a furnace, one must define what the furnace is.