A mid 20th century, single function, adjustable temperature safety control for home \u201cwinter air conditioner\u201d. Used for automatically shutting down the system to prevent over heating if, for example, the fan failed to come on allowing heat to build up in the furnace plennum beyond the safe operating point; equipped with helical bimetal heat sensor, single tilting mercury bulb line voltage switch, LA419, Minneapolis Honeywell, 1946. [1 of 2 similar to ID#238]<\/p>\n\n\n\n
Features:<\/strong> Technical Significance:<\/strong> Industrial Significance:<\/strong> A mid 20th century, single function, adjustable temperature safety control for home \u201cwinter air conditioner\u201d. Used for automatically shutting down the system to prevent over heating if, for example, the fan failed to come on allowing heat to build up in the furnace plennum beyond the safe operating point; equipped with helical bimetal heat sensor, single tilting mercury bulb line voltage switch, LA419, Minneapolis Honeywell, 1946. [1 of 2 similar to ID#238]<\/p>","protected":false},"author":1,"featured_media":20894,"comment_status":"closed","ping_status":"closed","template":"","cpt_portfolio_group":[209,206],"class_list":["post-20893","cpt_portfolio","type-cpt_portfolio","status-publish","has-post-thumbnail","hentry","cpt_portfolio_group-heating","cpt_portfolio_group-residential"],"yoast_head":"\n
\u2013 Original cable connector
\u2013 Original wiring harness stubs
\u2013 Original label with wiring diagram and specifications
\u2013 With original swivel compression mounting device allowing the postioning of the temperature sensor in the furnace hot air plennum<\/p>\n\n\n\n
\u2013 A mid 20th century, single function temperature limit safety controller exemplifying the materials and engineering know-how of the immediate pre W.W.II years.
\u2013 The Post W.W.II market for \u201cwinter air conditioning\u201d was enormous and the industry sensed the potential, but there was still the public concern over the safety of all automatic equipment operating unattended in the home.
\u2013 The development of affordable, reliable high temperature limit automatic shut off control was a key to achieving market potential. Sales people, installers and service people would make a point of pointing out the safety features, why and how they worked. Some sales people would carry one of these safety controllers with them to clinch a sale.<\/p>\n\n\n\n
\u2013 The simplicity of the controller is surely a hallmark of the times, reflecting sophisticated engineering and manufacturing methods, as well as the availability of the engineering materials needed
\u2013 This controller may be one of the first class of products to be built in Canada by Minneapolis Honeywell, for the then rapidly growing market \u2013 see dateline in side cover \u201cToronto 17\u201d
\u2013 Also made as a fan on-off controller, this series of limit safety controls by Honeywell would become the work horse of the industry throughout the major growth years of the winter air conditioner market in Canada, from the 1940\u2019s through 60\u2019s
\u2013 The original cable connector and wiring stubs tells the stories of the trade practices and materials of the times.<\/p>","protected":false},"excerpt":{"rendered":"