Method and system for controlling a modulating air conditioning system

• US 8,382,003 B2
• Filed: 11/21/2007
• Issued: 02/26/2013
• Est. Priority Date: 11/21/2007
• Status: Active Grant

• Current Assignee: Lennox Industries Incorporated (Lennox International Incorporated)
• Original Assignee: Lennox Industries Incorporated (Lennox International Incorporated)
• Inventors: Grohman, Wojciech
• Primary Examiner(s): Tyler, Cheryl J
• Assistant Examiner(s): Bradford, Jonathan
• Application Number:
  US11/944,225
• Publication Number:
  US 20090127346A1
• Time in Patent Office: 1,924 Days
• Field of Search: 236/46.C, 236/1.C, 700/276
• US Class Current: 236/1.C
• CPC Class Codes: F24D 19/1084 for air heating systems
• CPC Class Codes: G05D 23/1912 whose output amplitude can take more than two discrete values

Abstract

A method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat for satisfying an air conditioning load demand in a conditioned space includes: (a) operating the thermostat in a plurality of succeeding operating cycles to issue a first call signal or a second call signal indicating a first or second stage operation by the air conditioning system; the first and second stage operation being effected according to a first operating regimen to satisfy the air conditioning load demand; (b) operating the air conditioning system in response to the first and second call signals; the air conditioning system operating at a first power level when receiving the first call signal and operating at a predetermined second power level when receiving the second call signal; the first power level being established by the air conditioning system according a second operating regimen.

Claims

1. A method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat for satisfying an air conditioning load demand in a conditioned space;

the method comprising;

producing a first call signal, based on at least one previous operating cycle of said modulating air conditioning system, from said two-stage thermostat indicating a first stage operation of said modulating air conditioning system;

an output capacity of said first stage operation being determined by an average of a value of power used in said at least one previous operating cycle; and

producing a second call signal from said two-stage thermostat when said first call signal is not produced, indicating a second stage operation of said modulating air conditioning system, an output capacity of said second stage operation being greater than said output capacity of said first stage operation, and wherein said average of a value of said power is calculated by a sum of a percentage of said power used during a first time interval in said first stage and a percentage of said power used during a second time interval in said second stage.

2. The method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat as recited in claim 1 wherein said output capacity of said second stage is one hundred per cent of said modulating air conditioning system.

3. The method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat as recited in claim 1 wherein said modulating air conditioning system is at least one of a cooling system or a heating system.

4. The method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat as recited in claim 1 wherein said average of a value of power is an average of a value of power of a plurality of preceding operating cycles.

5. The method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat as recited in claim 1 wherein said output capacity of said first stage is less than one hundred percent of said modulating air conditioning system.

6. A method for manufacturing a modulating air conditioning system, comprising:

coupling a modulating furnace unit to a two-stage thermostat control unit, said two-stage thermostat configured to produce a first call signal, based on at least one previous operating cycle of said modulating air conditioning system, from said two-stage thermostat indicating a first stage operation of said modulating air conditioning system;

an output capacity of said first stage operation being determined by an average of a value of power used in said at least one previous operating cycle; and

producing a second call signal from said two-stage thermostat when said first call signal is not produced, indicating a second stage operation of said modulating air conditioning system, an output capacity of said second stage operation being greater than said output capacity of said first stage operation, and wherein said average of value power is calculated by a sum of a percentage of said power used during a first time interval in said first stage and a percentage of said power used during a second time interval in said second stage; and

coupling a thermostat control to said modulating air conditioning system and said two-stage thermostat control unit, said thermostat control unit configured to have an operating routine for implementing signals received from said two-stage thermostat control unit.

7. The method recited in claim 6 wherein said output capacity of said second stage operation is one hundred per cent of said modulating said air conditioning system.

8. The method recited in claim 6 wherein said modulating air conditioning system is at least one of a cooling system or a heating system.

9. The method recited in claim 6 wherein said output capacity of said first stage operation is less than one hundred percent of power level capability of said air conditioning system.

10. The method recited in claim 6 wherein said average of a value of power is an average of a value of power of a plurality of preceding operating cycles.

11. A system for satisfying an air conditioning load demand in a conditioned space;

the system comprising;

a modulating air conditioning system; and

a two-stage thermostat coupled with said modulating air conditioning system;

said two-stage thermostat configured to produce a first call signal, based on at least one previous operating cycle of said modulating air conditioning system indicating a first stage operation of said modulating air conditioning system, an output capacity of said first stage operation being determined by an average of a value of power used in said at least one previous operating cycle;

said two-stage thermostat further configured to produce a second call signal when said first call signal is not produced, indicating a second stage operation of said modulating air conditioning system, an output capacity of said second stage operation being greater than said output capacity of said first stage operation, and wherein said average of a value of power is calculated by a sum of a percentage of said power used during a first time interval in said first stage and a percentage of said power used during a second time interval in said second stage.

12. A system for satisfying an air conditioning load demand in a conditioned space as recited in claim 11 wherein said air conditioning system is at least one of a cooling system or a heating system.

13. A system for satisfying an air conditioning load demand in a conditioned space as recited in claim 11 wherein said output capacity of said second stage operation is one hundred per cent of said modulating air conditioning system.

14. A system for satisfying an air conditioning load demand in a conditioned space as recited in claim 11 wherein said output capacity of said first stage operation is less than one hundred per cent of said modulating air conditioning system.

15. A system for satisfying an air conditioning load demand in a conditioned space as recited in claim 11 wherein said average of a value of power is an average of a value of power of a plurality of preceding operating cycles.