Refrigerating and Air Conditioning Pressure and Temperature Controls – Household
An early, “low side” refrigeration system pressure control, for controlling evaporator temperature, equipped with 5 point, manual adjustable setting. Devised by Frigidaire in the 1920’s, it was to be a viable alternative to direct temperature-sensing technology, then in a crude stage of development, Frigidaire, Circa 1926. One of a rare set of 5 controllers, demonstrating the range of applications devised by Frigidaire, the various stages of deterioration expected, due to natural use, misuse, abuse and abandonment.
Some models, such as this one, used on household cabinet refrigerators, included a front-mounted, “cold control”, with off position and 5 temperature settings. This allowed the owners to adjust the temperature of the refrigerator, over a limited range of suction pressures without calling the service mechanic.
Technical Significance:
The significance of the device lies in the immense ingenuity it demonstrates in the period, in conceiving ways to automatically start and stop a refrigeration system at a predetermined temperature.
For it was a time in which little was known and understood about automatic sensors and electric control and regulation devices. The very notion of a mechanical device which would start and stop with out the touch of human hand was worrying. For much of the population of the time was brought up to be wary of gadgets of all varieties, often portrayed as mere hoaxes, possibly dangerous, and not to be trusted.
