Recovery process for heat pump system

• US 5,402,845 A
• Filed: 03/04/1994
• Issued: 04/04/1995
• Est. Priority Date: 03/04/1994
• Status: Expired due to Term

• Current Assignee: Carrier Corporation (Carrier Global Corporation)
• Original Assignee: Carrier Corporation (Carrier Global Corporation)
• Inventors: Jeffery, Harold L., Hickenlooper, Harrison T. III
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US08/206,785
• Time in Patent Office: 396 Days
• Field of Search: 165/29, 165/12, 236/46 R, 236/49.3, 62/231
• US Class Current: 165/208
• CPC Class Codes: F24D 19/1087 system using a heat pump
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 11/64 using pre-stored data
• CPC Class Codes: F24F 11/76 by means responsive to temperature, e.g. bimetal springs
• CPC Class Codes: F24F 11/84 using valves
• CPC Class Codes: F24F 11/86 by controlling compressors within refrigeration or heat pump circuits
• CPC Class Codes: F24F 3/044 Systems in which all treatment is given in the central station, i.e. all-air systems
• CPC Class Codes: F24H 15/269 Time, e.g. hour or date
• CPC Class Codes: F24H 15/33 Control of dampers
• CPC Class Codes: F24H 15/375 Control of heat pumps
• CPC Class Codes: G05D 23/1934 each space being provided with one sensor acting on one or more control means
• CPC Class Codes: G05D 23/20 with sensing elements having variation of electric or magnetic properties with change of temperature G05D23/13 takes precedence
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A process for noting in advance when a change in set point temperature is to occur in one or more zones. A heating stage is prematurely activated and dampers are selectively opened in the one or more zones that are about to experience changes in set point temperature. Activation of a second stage of heating is not permitted unless the zone temperature is lagging the current set point.

Claims

1. In a heating system having at least two separate stages of heating, a process for selectively activating the heating stages comprising the steps of:

monitoring at least one zone to be heated by said heating system for a future change in the set point temperature of the zone;

activating a first heating stage when the future change in set point temperature is to occur within a predefined period of time; and

adjusting the position of a damper associated with the zone to be heated so as to maximize the flow of heat to the zone.

2. The process of claim 1 wherein said step of monitoring at least one zone comprises the step of:

setting a flag denoting that a future change in set point temperature is to occur within a predefined period of time.

3. The process of claim 2 wherein said step of activating a first heating stage when the future change in temperature is within a predefined period of time comprises the steps of:

comparing the current temperature in the zone with the current set point temperature for the zone;

checking the value of the flag denoting when a further change in the set point is to occur within a predefined period of time when the difference between current set point and current temperature for the zone is less than a threshold value necessary to switch the first stage of heating on; and

activating the first stage of heating if the value of the flag indicates that a future change in set point is to occur within a predefined period of time for the zone.

4. The process of claim 3 wherein said step of adjusting the position of a damper associated with the zone to be heated comprises the steps of:

calculating a damper position based upon the difference between current set point and current temperature in the zone to be heated;

checking the value of the flag denoting when a future change in set point is to occur within a predefined period of time; and

overriding the calculated damper position with a predetermined open position when the flag indicates a future change in set point is to occur within a predefined period of time.

5. The process of claim 3 further comprising the step of:

calculating the difference between current set point and the current temperature of the zone to be heated; and

activating the second stage of heating only if the calculated difference exceeds a predefined threshold value for activating the second stage of heating.

6. The process of claim 2 further comprising:

comparing a scheduled time indicating when the change in set point temperature is to occur with the current time; and

resetting the flag when the current time exceeds the scheduled time.

7. In a system having a plurality of zones to be heated or cooled by a heat pump, a process for activating the heat pump comprising the steps of:

monitoring the zones for future changes in the set point temperature in the zones;

activating a heat pump when the future change in set point temperature for any zone is to occur within a predefined period of time; and

adjusting the position of a damper associated with any zones having further changes in set point temperatures occurring within the predefined period of time.

8. The process of claim 7 wherein said step of monitoring the zones for future changes in set point temperatures comprises the step of:

setting a flag for each zone denoting that a future change in set point temperature is to occur for that zone within a predefined period of time.

9. The process of claim 8 wherein said step of activating the heat pump when the future change in temperature is within a predefined period of time comprises the steps of:

comparing the current temperature in each zone with the current set point temperature for the zone;

checking the value of the flag for the zone to determine whether a future change in set point is to occur within a predefined period of time when the difference between current set point and current temperature for the zone is less than a threshold value necessary to switch the first stage of heating on; and

activating the heat pump if the value of the flag indicates that a future change in set point is to occur within a predefined period of time for the zone.

10. The process of claim 9 wherein said step of adjusting the position of a damper associated with the zones having changes set point to occur within predefined period of time comprises the steps of:

calculating a damper position based upon the difference between current set point and current temperature for each zone; and

checking the value of the flag for each zone denoting whether a future change in set point is to occur within a predefined period of time for the particular zone; and

overriding the calculated damper position for each zone with a predetermined open damper position for each zone having a flag that indicates a future change in set point is to occur within a predetermined period of time.

11. The process of claim 8 further comprising the step of:

reading the scheduled times in which the next changes in set point temperature are scheduled to occur in each zone; and

resetting the flags of any zones when the current time exceeds the noted scheduled times for these zones.