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The chip heater is a single point, tankless, domestic hot water system popular in Australia and New Zealand from the 1880s until the 1960s. Examples of this form of domestic water heating are still in current use.
The chip heater consisted of a cylindrical unit with a fire box and flue, through which a water pipe was run. Water was drawn from a cold water tank and circulated through the fire box. When heated, the water was drawn off to the area where it was used, typically in a bath or shower. There often was an ash box under the fire box, which allowed air under the fire, as well as various dampers in the flue.
Water had to be run at a trickle in order to heat up to a desirable temperature. The rate of combustion was controlled by the flues and the ash box. With lots of fuel and open flues the water could boil quickly, which was not a desirable result. With practice the correct combination of fuel, flue settings and water flow could result in enough hot water for a shower or bath in approximately 20 minutes.
The chip heater is embedded in Australian and New Zealand social history as many people can remember using one or someone who had one. The precise history of the chip heater is unclear.
The original idea surely must be derived from vertical steam boilers. Miles Lewis notes that the "instantaneous water heaters," which were being sold by Douglas & Sons of Melbourne by 1888 were probably chip heaters. In 1892, an advertisement in Melbourne promised that Fischer's Patent Bath Heater could be heated with wood in three minutes at the cost of one farthing.
Catalogs from the National Radiator Company between 1913 and 1919, which were marketed in Australia, do not show chip heaters. This suggests that the chip heater was a local innovation.
The chip heater was very similar to the gas and kerosene powered “geyser” hot water heaters popular in Australian suburban residences from the 1920s. The main difference was the fuel source. The Australian producer Metters Limited supplied gas geysers for city clients (who had access to gas) and chip heaters for country clients.
There were a number of manufacturers and brands. According to Professor Miles Lewis, the early twentieth century brands included the Royal, Little Hero, Silver Ace, Kangaroo, Empire and Little Wonder. Peter Wood recalls a “Torrens” brand being popular in Adelaide.
Metters had a variety of chip heaters in its 1936 catalog, including oil and kerosene-powered chip heaters. Metters claimed a flow of 2 gallons of “very hot water” per minute.
Archer, John, 1998, Your home: the inside story of the Australian house, Port Melbourne, Lothian.
Metters Ltd 1936 Metters' bath heater and hot water service : sectional catalogue, Metters Ltd.
Oliver, Julie. The Australian home beautiful: from Hills hoist to high rise, McMahon's Point, N.S.W. Home Beautiful, 1999.
Postings on the NSW Heritage Office Heritage Advisors Discussion Group by Peter Benkendorff, David Beauchamp, Susan Duyker, Elizabeth Roberts and Peter Woods, April 2007.
Posting on Engineering Heritage discussion group by Professor Miles Lewis 26 April 2007