Thermostat having default curtailment temperature settings

1. A thermostat for controlling the operation of one or more systems and restricting operation to a desired level, the thermostat comprising:

a receiver means for receiving signals transmitted by a utility provider, to provide the thermostat with usage rate schedule signal information;

a memory means for storing the transmitted usage rate schedule information, and a plurality of control set points for each system for each of the usage rate schedule periods; and

a processor that looks up the appropriate stored control set point for each system for the current usage rate schedule period, and controls each system using the appropriate set point to maintain a desired operating level for each system during each usage rate schedule period, wherein when the receiver means receives a signal transmitted by a utility provider requesting the thermostat to enter into a curtailment mode of operation, the thermostat responsively discontinues operation of one or more systems for a first predetermined time period, and

wherein the thermostat further comprises a second predetermined time period following the first time period, during which the thermostat looks up a control set point corresponding to the curtailment mode of operation for one or more systems and uses the control set point to control the operation of one or more systems.

2. A thermostat capable of controlling the operation of one or more systems and restricting system operation to a desired level, the thermostat comprising:

a receiver means for receiving signals transmitted by a utility provider communicating a usage rate schedule or a request for curtailment mode;

a memory means for storing the transmitted usage rate schedule or curtailment request information, and for storing a control set point for each system for each of the rate schedule periods;

a processor that looks up the appropriate control set point for each system for the current usage rate schedule period, and controls each system using the appropriate set point for maintaining a desired operating level for each system during each rate schedule period; where in response to a request for curtailment mode of operation, the processor responsively discontinues operation of one or more systems for a first predetermined time period, and wherein the processor looks up a stored control set point value corresponding to a curtailment mode period for each system, and uses the control set point to control the operation of one or more systems for a second predetermined time period following the first predetermined time period.

3. An improved digital thermostat capable of receiving signals transmitted by a utility provider communicating a usage rate period schedule or a request for a load curtailment period, the improvement comprising:

a memory means for storing a predetermined set point temperature for each usage rate period;

a processor that chances the control set point for controlling the operation of a climate control system to the stored predetermined set point temperature corresponding to the current usage rate period, wherein the processor discontinues thermostat operation for a first minimum predetermined time period upon receiving a request for a load curtailment period from a utility provider;

where the processor changes the control set point to the stored predetermined temperature set point corresponding to a load curtailment period after the first minimum predetermined time period expires, and maintains the temperature set point for a second predetermined time period that begins after the first time period and ends at the completion of the load curtailment period.

4. The improved digital thermostat of claim 3 , wherein the user may manually override the load curtailment period at the thermostat.

5. The improved digital thermostat of claim 4 , wherein the manual override comprises an input to the thermostat to adjust the control set point temperature.

6. The improved digital thermostat of claim 5 , wherein the manual override further comprises a temporary predetermined time period, after which the thermostat restores the control set point temperature to the predetermined temperature set point corresponding to the current usage rate period.

7. The improved digital thermostat of claim 6 , wherein the thermostat transmits a signal to the utility provider to communicate information indicating an override has been initiated by the user of the thermostat.