Abstract: Energy saving temperature and humidity sensing and control processes, system and apparatuses operate effectively in response to signals received from occupants and to dynamic responses of building and its heating, ventilating and air conditioning system. The disclosed processes, apparatuses and system utilize thermostats equipped with a drift ramping and hold time to save energy; the thermostats only need resetting to a neutral comfort set point which is accomplished by means of a push button or touch plate. The disclosed systems are pre-programmed and set so that occupants will be comfortable although the temperature within the building drifts because the rate of drift is controlled to a gradual and normally unnoticed change.

Abstract: A refrigerator includes a compressor, a condenser, an evaporator, an evaporator fan and a temperature sensing circuit which includes a thermistor located to sense the average temperature of the cabinet air and a potentiometer manually adjustable to a desired temperature set point. The temperature sensing circuit also includes a first comparator stage which indicates whether the average temperature of the cabinet air is above or below a first value, the first comparator having little or no hysteresis in its response so that small changes in temperature can be detected. A second comparator stage indicates whether a signal at its input is greater or less than a second value, the second comparator stage having substantial hysteresis in its response to provide high noise immunity. An integrator is interposed between the first comparator stage and the second comparator stage to further enhance noise suppression.

Abstract: A double walled smoke stack is made up of stackable sections. The top part of each section has a member extending between inner and outer shells and is either downwardly prestressed towards the inner shell or is flexible. This allows the inner shell to upwardly expand.

Abstract: There has been provided an improved process control optimizer for regulating at least one parameter of the process relative to optimum utilization of available energy. Temperature responsive open loop control means regulates the fuel flow and the optimizer is operatively responsive to the fuel flow for regulating air flow for combustion of fuels such that the fuel air mixture is minimized. The improvement includes a means for delivering a digital output code for governing the air mixture in accordance with the optimum characteristic of the process and digitally responsive means receive said codes for decreasing air at a selected first rate and increasing air at a relatively faster second rate, the rates corresponding to respective reductions and increases in fuel flow about a selected optimum operating point.

Abstract: A ventilated cap which is placed over the opening in the ridge of a roof and which includes a pair of beveled edged vent parts. Each vent part has transversely oriented openings therein which extending from one beveled side edge to the other of the part. The vent parts are placed side edge to side edge over the opening in the roof ridge and secured to the underlying roof sides. Shingles are placed over the top of the vent parts in overlapping fashion with the outer beveled side edges of the parts being exposed but underlying said shingles to vent said roof.