An example of innovative, mid 20th century combustion safety control technology that would dominate the field of household automatic oil heating through much of the balance of the century; stack mounted, bimetal heat actuated safety switching, electro-magnetic relay controlled; equipped for intermittent ignition, heat anticipation, 3 wire room thermostat, Type RA117A, 25 cycle, Minneapolis Honeywell, Toronto Circa 1945. [See also ID#235]<\/p>\n\n\n\n
Features:<\/strong> Technical Significance:<\/strong> Industrial Significance:<\/strong> An example of innovative, mid 20th century combustion safety control technology that would dominate the field of household automatic oil heating through much of the balance of the century; stack mounted, bimetal heat actuated safety switching, electro-magnetic relay controlled; equipped for intermittent ignition, heat anticipation, 3 wire room thermostat, Type RA117A, 25 cycle, Minneapolis Honeywell, Toronto Circa 1945. [See also ID#235]<\/p>","protected":false},"author":1,"featured_media":20884,"comment_status":"closed","ping_status":"closed","template":"","cpt_portfolio_group":[209,206],"class_list":["post-20883","cpt_portfolio","type-cpt_portfolio","status-publish","has-post-thumbnail","hentry","cpt_portfolio_group-heating","cpt_portfolio_group-residential"],"yoast_head":"\n
\u2013 Pristine enclosure in high gloss grey, a break in tradition with the \u201cblack look\u201d of heating control devices
\u2013 Handsome corporate monograph in distinctive Minneapolis Honeywell red
\u2013 Original wiring diagram on inside of cover<\/p>\n\n\n\n
\u2013 Of special significance is the 25cycle engineering of this controller, built for the Ontario market in the period prior to frequency standardization, which took place in the closing years of the 1940\u2019s in much of the province. These devices being electro-magnetic were frequency sensitive. The large rear mounted transformer used to provide control circuit power tells the story. The 6o cycle equivalent is shown on item ID#235.
\u2013 With the introduction of new generation of integrated, relatively reliable control systems for household heating in the early 1940\u2019s a new era of mass produced technology had arrived, setting the stage for a new, Canadian mass market.
\u2013 It combined up-dated, bimetal combustion control technology with the three wire, heat anticipating thermostat, \u2013 providing comfort, safety and reliability levels unheard of a decade earlier.
\u2013 By the early 1940\u2019s Minneapolis Honeywell\u2019s unitary designed, combustion controller, the RA117A Protectorelay, had arguably become a kind of standard of achievement for the home, automatic, oil heating industry in much of Canada.
\u2013 The fragile and potentially poisonous mercury bulb switching of earlier combustion controls was replaced here with quiet, reliable, electro-magnetic and bimetal driven snap action contacts,
\u2013 A significant design consideration in the development of unitary, stack-mounted controls was the high ambient temperatures to which they were subjected. High temperature wiring and heat shielding were new design requirements to be dealt with.
\u2013 These embryonic, electric automated systems were representative of the earliest introduction of complex systems into the Canadian home. See Note #2<\/p>\n\n\n\n
\u2013 This pristine control, un-used, was a factory reconditioned, control by Minneaplolis Honeywell, Toronto. It exemplifying the great care taken in recycling of equipment, part of the practice and conservation ethic of the day, delivering
reliable reconditioned equipment to a market that desperately needed it .
\u2013 It was a period quite different from that which would exist towards the end of the century, where damaged and un-reliable equipment would be declared expendable, too costly or superseded, as a result of rapid technological, design or manufacturing changes.
\u2013 By the mid 1940\u2019s the HVACR industry recognized that a new era in the popularization of automatic home heating equipment was under way. Unitary designed, oil home heating equipment had evolved into a \u201chome appliance\u201d, on which many householders would now become heavily dependent.
\u2013 This new, widespread dependency on automatic heating, throughout Canada\u2019s long cold winters, would require the industry to strive for enhanced performance in matters of reliable, maintainable and readily serviceable equipment, with readily obtainable replacement parts.
\u2013 Public expectations for 24 hour emergency service was part of the new world of popular technology that had been created. Honeywell and other manufacturers would respond by providing a line of rebuilt controls for field service people to stock for emergency purposes.<\/p>","protected":false},"excerpt":{"rendered":"