How big is your carbon footprint? Well it can go down a few shoe sizes when you get solar installed. The beauty of solar is that it can be used to heat and cool your home with no global climate impact. It takes energy to make heat, when energy is made it pollutes the atmosphere, when we use existing solar energy it does not. Burning wood for heat creates the most pollution. Natural gas or oil, both cause pollution when they burn, but natural gas emits less pollution than oil. So what about electric heat? When electricity is created at a power plant it creates pollution, especially when they use coal or natural gas.
Yes? Well you have come to the right page for information about what to do next.
The first question that comes to mind is should it be repaired or replaced? (Pictured below, older unit, rusting, dirty, likelyhood of more repairs is high.)
A PG&E representative recently suggested to start looking for a new furnace when yours is at about 12-15 years old, other sources I checked with all appear to fall within the same range although many suggest 15 years. 15 years is about the average life of the normal furnace. There are factors that affect this like regular preventative maintenance and usage.