Natural gas furnaces are the most common source of residential heat in the Seattle / Tacoma area. This is due in part to many years of “gas line extension” infrastructure put in place by local utilities such as PSE. Despite the expansion of natural gas service, many older neighborhoods still do not have natural gas service readily available. Fuel oil-fired furnaces are common in these areas. While fuel oil provides excellent comfort it has many disadvantages such as high cost, need to refill tanks, dirty combustion, and a distinctive odor which sometimes permeates conditioned space. As fuel oil furnaces reach the end of their useful life they are frequently replaced with different heating sources.
In some cases, natural gas has become available and a traditional gas furnace is installed. When gas is not available, ductless split and heat pump systems are attractive options for many homeowners. Improved efficiency (think lower energy bills), cleanliness, and convenience are big benefits. The installed base of oil furnaces is steadily declining as these newer, more efficient HVAC systems are installed.