Heating and air-conditioning systems must be sized to maintain a comfortable building environment based upon a certain coldest or hottest day of the year. Because most days creating heating or cooling demand are not at those design point extremes. Therefore, the heating and air conditioning system is oversized much of the year. Most heating and air conditioning systems operate at the "full-on" BTU level regardless of the outdoor temperature that determines the demand or heat loss characteristics of a controlled space. The Tomorrow House family of HVAC controllers help compensate for "over-sizing" and delivery systems designed for extremes by controlling HVAC system "on" cycles, to produce a more even energy distribution and usage which increases overall air-conditioning efficiency, resulting in reduced heating and air-conditioning utility bills.

The operating principle is simple and proven; by sensing when the system reaches thermal saturation*, the controller adjusts the system's operating cycle to maximize the use of the energy that is needed in the controlled space and HVAC system of the building envelope. The lower average temperature resulting from the Thermostat-Plus design strategy is distributed effectively and reduce energy consumption that is backed by an at least 20% savings guarantee.

The TomorrowHouse Controllers do not replace the thermostat; it works with the thermostat to more effectively control the heating and/or air-conditioning system. However, unlike a typical thermostat, the controller links to the thermostat and mounts directly to the supply plenum and acts in response to demand of the actual HVAC system rather than reacting by temperature alone at the thermostat location. After a simple calibration, the controllers that give the Plus to the thermostat it is tuned directly to the system it controls.

During operation, the TomorrowHouse Controller interrupts the heating and/or cooling cycle, after the system has reached thermal saturation at the demand condition, however, it does not interrupt the operation of the air handler (blower). Return air and supply air continue to cycle through the HVAC system and building envelope. This operational mode allows latent energy to be effectively and in a more balanced way be distributed throughout the envelope.

The demand sensing TH-X family of Thermostat-Plus ad-on devices responds to the demand condition from temperature change known as delta-T or T. Return air and supply air align during the TH-X regulated cycle demonstrating effective even and comfort balanced heating in the controlled space. For more information about HVAC Controllers please click here.