Heat pump system having a maximum percent demand re-calculation algorithm controller

Patent metadata

Field	Value
Publication number	US-9759466-B2
Application number	US-201414198046-A
Country	US
Kind code	B2
Filing date	Mar 5, 2014
Priority date	Mar 5, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

One aspect presents a controller that comprises a control board, a microprocessor located on and electrically coupled to the control board, and a memory coupled to the microprocessor and located on and electrically coupled to the control board. The controller is configured to receive an operating parameter signal and recalculate a first maximum heating % demand to a second maximum heating % demand that is greater than the first maximum heating % demand, when a value of the operating parameter signal exceeds a predetermined value, and operate the HP system based on the second maximum heating % demand.

First claim

What is claimed is:

1. A heat pump (HP) system, comprising:
an indoor system comprising an indoor heat exchanger equipped with an indoor blower;
an outdoor system comprising an outdoor heat exchanger equipped with an outdoor fan, said indoor system and said outdoor system being fluidly coupled together by refrigerant tubing that forms a refrigerant system;
an operating parameter sensor associated with said indoor system or said outdoor system and configured to provide an operating parameter signal of said indoor system or said outdoor system; and
a controller coupled to said HP system, wherein, prior to receiving a refrigerant high pressure trip signal from a refrigerant high pressure trip sensor, the controller is configured to:
operate said HP system based on a first maximum heating % demand;
determine whether said operating parameter signal indicates that a current heating % demand exceeds said first maximum heating % demand;
responsive to a determination that said operating parameter signal indicates that the current heating % demand exceeds said first maximum heating % demand, set said first maximum heating % demand to a second maximum heating % demand that is greater than said first maximum heating % demand and operate said HP system based on said second maximum heating % demand;
wherein said controller sets said first maximum heating % demand as follows:
first maximum heating % demand/% indoor airflow rate= A+{B ×((ODT_ref+ C )/(ODT+ D ))^ N},

wherein:
first maximum heating % demand is an initial maximum limit heating % demand of said HP system, ODT_ref is a reference outdoor temperature in degrees Fahrenheit adjusted for a given HP system, ODT is the outdoor temperature in degrees Fahrenheit, % indoor airflow rate=indoor airflow rate/indoor airflow rate @100% heating demand, where indoor airflow rate is airflow output of the indoor system, and where A, B, C, D, and N are real numbers; and

wherein said controller sets said second maximum heating % demand as follows:
second maximum heating % demand/% indoor airflow rate= A+{B ×((ODT_ref+ C )/(ODT+ D ))^ N},

wherein:
second maximum heating % demand is the maximum heating % demand after recalculation of said first maximum heating % demand of said HP system, ODT_ref is a reference outdoor temperature in degrees Fahrenheit adjusted for a given HP system, ODT is the outdoor temperature in degrees Fahrenheit, % indoor airflow rate=indoor airflow rate/indoor airflow rate @100% heating demand, where indoor airflow rate is airflow output of the indoor system, and where A, B, C, D, and N are real numbers selected such that said second maximum heating % demand value is greater than said first maximum heating % demand.

2. The HP system of claim 1 , wherein said controller is further configured to increment a heating % demand towards said second maximum heating % demand when a discharge air temperature of said indoor system is equal to or less than a discharge air temperature set point of said indoor system.

3. The HP system of claim 2 , wherein said controller increments said heating % demand as follows:
Incremented heating % demand=current heating % demand+ D ×(second maximum heating % demand current heating % demand),

wherein D is a real number having a value between zero and 1.

4. The HP system of claim 1 , wherein said controller is configured to test operating parameters of said HP system at a set time interval and reset operating parameters of said HP system to operational settings based on said first maximum heating % demand.

5. The HP system of claim 1 , wherein said controller is configured to reset said HP system to operational settings based on said first maximum heating % demand when an outdoor temperature reaches a predetermined value.

6. The HP system of claim 1 , wherein said HP system, when operating based on said second maximum heating % demand, is further configured to receive the refrigerant high pressure trip signal from a refrigerant high pressure trip sensor and recalculate said second maximum heating % demand to a third maximum heating % demand based on a current heating % demand existing when said controller receives said refrigerant high pressure trip signal and operate said HP system based on said third maximum heating % demand.

7. The HP system of claim 6 , wherein said controller recalculates said third maximum heating % demand, as follows:
Third maximum heating % demand= B ×current heating % demand at trip signal,

wherein:
B is a real number having a value between zero and 1.

8. A heat pump (HP) system controller, comprising:
a control board;
a microprocessor located on and electrically coupled to said control board; and
a memory coupled to said microprocessor and located on and electrically coupled to said control board and having a controller couplable to an operating parameter sensor associated with an indoor system or an outdoor system of a heat pump (HP) system;
wherein, prior to receiving a refrigerant high pressure trip signal from a refrigerant high pressure trip sensor, said controller is configured to:
operate said HP system based on a first maximum heating % demand;
determine whether an operating parameter signal indicates that a current heating % demand exceeds said first maximum heating % demand;
responsive to a determination that said operating parameter signal indicates that the current heating % demand exceeds said first maximum heating % demand, set said first maximum heating % demand to a second maximum heating % demand that is greater than said first maximum heating % demand and operate said HP system based on said second maximum heating % demand;
wherein said controller sets said first maximum heating % demand as follows:
first maximum heating % demand/% indoor airflow rate= A+{B ×((ODT_ref+ C )/(ODT+ D ))^ N},

wherein:
first maximum heating % demand is an initial maximum limit heating % demand of said HP system, ODT_ref is a reference outdoor temperature in degrees Fahrenheit adjusted for a given HP system, ODT is the outdoor temperature in degrees Fahrenheit, % indoor airflow rate=indoor airflow rate/indoor airflow rate @100% heating demand, where indoor airflow rate is airflow output of the indoor system, and where A, B, C, D, and N are real numbers; and
wherein said controller sets said second maximum heating % demand as follows:
second maximum heating % demand/% indoor airflow rate= A+{B ×((ODT_ref+ C )/(ODT+ D ))^ N},

wherein:
second maximum heating % demand is the maximum heating % demand after recalculation % demand of said HP system, of said first maximum heating ODT_ref is a reference outdoor temperature in degrees Fahrenheit adjusted for a given HP system, ODT is the outdoor temperature in degrees Fahrenheit, % indoor airflow rate indoor airflow rate/indoor airflow rate @100% heating demand, where indoor airflow rate is airflow output of the indoor system, and where A, B, C, D, and N are real numbers selected such that said second maximum heating % demand value is greater than said first maximum heating % demand.

9. The HP system controller of claim 8 , wherein said controller is further configured to increment said heating % demand towards said second maximum heating % demand when a discharge air temperature of said indoor system is equal to or less than a discharge air temperature set point of said indoor system.

10. The HP system controller of claim 9 , wherein said controller increments said heating % demand as follows:
Incremented heating % demand=current heating % demand+ D ×(second maximum heating % demand current heating % demand),

wherein D is a real number having a value between zero and 1.

11. The HP

Assignees

• Lennox Ind Inc

Inventors

• Goel Rakesh
• Berg Eric
• Hrejsa Pete

Classifications

• F24F11/30 Primary

  for purposes related to the operation of the system, e.g. for safety or monitoring · CPC title

• F24F2140/00

  Control inputs relating to system states · CPC title

• F24F11/871

  by controlling outdoor fans · CPC title

• F24F11/77

  by controlling the speed of ventilators · CPC title

• F24F11/63

  Electronic processing · CPC title