Editing Block heater (section)

== Purpose ==
Pre-heating of an engine is primarily used to make it easier to start.  Added benefits are:
*The cabin heater produces heat sooner for comfort and to [[Defogger|thaw]] the windscreen.<ref name="Anchorage">{{cite web|url=http://www.muni.org/Departments/health/environment/AirQ/Pages/WhyPlug20F.aspx |title=Why plug at 20 degrees? |website=www.muni.org |url-status=dead |archive-url=https://web.archive.org/web/20110114212923/http://www.muni.org/Departments/health/environment/AirQ/Pages/WhyPlug20F.aspx |archive-date=14 January 2011}}</ref>
*Reduction of condensation of fuel on cold cylinder walls during start thus
** saving fuel and reducing [[Vehicle emissions control|exhaust emissions]] and 
** reducing oil dilution by gasoline scraped into the oil pan by the piston rings.
*The engine reaches operating temperature sooner, so the engine does not run rich as long.  This further reduces fuel consumption and emissions.
*Less load on the starter and battery thereby prolonging their service lives.
*Less engine wear as oil circulation is improved.
*Reduces the need for a [[Remote starter]], thereby further saving fuel and emissions.

Block heaters or coolant heaters are also found on the diesel engines in [[standby generator]]s, to reduce the time taken for the generator to reach full power output in an emergency.