hot water heater

• hot-water heater, hotwater heater

hot water heater (plural hot water heaters)

1. An apparatus, usually fuel-burning, electric or solar-powered, in which water is heated to be used directly as domestic hot water or process hot water (but not for supplying space heating, calorifiers etc, for which a boiler or furnace is used).
   • 1977, Kaiman Lee, Encyclopedia of Energy-Efficient Building Design: 391 Practical Case Studies:

     This [warm-air heated] house has a supplemental electric hot water heater and an oil furnace.

   • 2003, Blair Allen, Julie Jones Lloyd Kahn, Septic System Owner's Manual:

     This system has an insulated 5-gallon electric hot water heater directly under the sink.

   • 2004, Black & Decker, The Complete Photo Guide To Home Repair:

     It's a good idea to insulate at least the first ten feet of the hot- and cold-water lines coming out of the hot water heater.

   • 2004, Mohammad A Malek, Power Boiler Design, Inspection, and Repair:

     A hot water heater is a potable water boiler in which the operating pressure does not exceed 160 psi and/or temperature does not exceed 210 °F.

• Some people object to the use of the term hot water heater and prefer simply water heater, since water that is already hot does not require heating.

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