soft, raised surface upon cloth, mid-14c., downy plumage, from Anglo-French pyle or Middle Dutch pijl, both from Latin pilus a hair (source of Italian pelo, Old French pel). Phonological evidence rules out transmission of the English word via Old French cognate peil, poil. Meaning nap upon cloth is from 1560s.
Updated 01/08/17. 1  of 06. Gas Furnace Types and Efficiency Ratings BanksPhotos / Getty Images The gas furnace in your home is a critically important appliance and one you depend on to work reliably, efficiently and quietly. 2  of 06. Low Efficiency Furnace: 55% to 72% AFUE (obsolete technology) Characteristics. 3  of 06.
A gas valve for a furnace is made up of four major parts that include a manual valve, a regulator, a solenoid valve and a pilot safety. The manual valve is turned by hand to shut off gas supply to the furnace completely. In older furnaces, this valve is a component of a gas chain, and it is open when the handle aligns with the gas pipe. The regulator reduces gas pressure from a gas line to a more manageable pressure for the manifold to distribute to the burners.