Control system for a room air conditioner and/or heat pump

• US 9,535,408 B2
• Filed: 04/19/2010
• Issued: 01/03/2017
• Est. Priority Date: 11/24/2009
• Status: Active Grant

• Current Assignee: Friedrich Air Conditioning, LLC
• Original Assignee: Friedrich Air Conditioning Company
• Inventors: Lingrey, David J., Eicher, Kevin L., Cagle, George
• Primary Examiner(s): JARRETT, RYAN A
• Application Number:
  US12/762,841
• Publication Number:
  US 20110125328A1
• Time in Patent Office: 2,451 Days
• Field of Search: 700/276, 700/278, 702/183
• US Class Current: 1/1
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 23/0256 injecting test signals and analyzing monitored process response, e.g. injecting the test signal while interrupting the normal operation of the monitored system; superimposing the test signal onto a control signal during normal operation of the monitored system

Abstract

A universal control system is provided for a room air conditioner or heat pump that has a number of sensor inputs. An electronic control system with a microcontroller and microcomputer are used to provide a large number of operations that can be performed by (1) manufacturer, (2) end users and (3) maintenance personnel. The manufacturer can load different versions of a software program to match the unit. The end user can program in a large number of different conditions or schedules the end user finds desirable, plus the end user is advised of maintenance requirements or faults. The maintenance personnel may perform diagnostics, determine fault history, upload improved or replacement software, as well as the numerous maintenance functions normally performed by maintenance personnel.

Claims

1. An electronic control system for communicating with an end user of a room air conditioner and/or heat pump having a compressor, an accumulator, refrigerant/heating fluid, outdoor coil, indoor coil, reversing valve, cooling/heating capillary tube, a fan and a blower;

said electronic control system comprising;

sensor inputs for determining (a) pressure of said refrigerant/heating fluid, (b) temperature of indoor air, (c) temperature of outdoor air, (d) temperature of said outdoor coil, (e) temperature of said indoor coil, (f) temperature of air on discharge side of said indoor coil and (g) humidity of indoor air;

outputs for controlling (a) said compressor, (b) said reversing valve, (c) said fan and (d) said blower;

between said sensor inputs and said outputs being located a main control and a user interface connected thereto, said main control including a microcontroller and said user interface including a microcomputer;

said microcontroller performing diagnostic testing to detect faults in said air conditioner/heat pump and, if a fault or faults are detected, provide a fault indication to an end user via said user interface;

said microcomputer recording a history of said fault or said faults;

said microcomputer of said user interface operates a display and control switches communicating to, and receiving communication from, said end user;

said display is white on black using twisted nematic technology;

said microcontroller has control and processing algorithms therein to regulate said outputs, said microcontroller running diagnostic routines to monitor the health of said room air conditioner and/or heat pump and, if a health problem is detected, take corrective action based upon severity of said detected health problem; and

a heater coil so that if said outside coil begins to freeze up and needs to be reverse cycled, said outputs may also control said heater coil to provide heat during said reverse cycling.

2. The electronic control system for communicating with an end user of a room air conditioner/heat pump as recited in claim 1, wherein said microcontroller includes a scheduler for scheduling different temperatures at different times.

3. The electronic control system for communicating with an end user of a room air conditioner/heat pump as recited in claim 2, wherein said scheduler is for seven days a week with four different time periods per day.

4. The electronic control system for communicating with an end user of a room air conditioner/heat pump as recited in claim 1, wherein said microcomputer has remote access for diagnostics, testing, maintenance and/or upgrades.

5. The electronic control system for communicating with an end user of a room air conditioner/heat pump as recited in claim 4, wherein said user interface has an infrared port for receiving communications from a remote control in addition to said communications by said end user at said user interface.

6. The electronic control system for communicating with an end user of a room air conditioner/heat pump as recited in claim 5 further comprising drivers for receiving said outputs and operating said compressor, said reversing valve, said fan, said blower and said heater coil.

7. A method of operating an HVAC system by an end user for room temperature control, said method including the following steps:

sensing various conditions including (a) pressure of a refrigerant/heating fluid, (b) temperature of indoor air, (c) temperature of outdoor air, (d) temperature of an outdoor coil, (e) temperature of an indoor coil, (f) temperature of air on a discharge side of said indoor coil and (g) humidity of said indoor air;

continuously providing information from said sensing step into a microcontroller;

programming said microcontroller to process said information to send outputs for controlling (a) a compressor, (b) a reversing valve, (c) speed of a blower, (d) speed of a fan, and (e) a heater;

communicating with said end user conditions of said HVAC system via a user interface, said user interface using negative nematic field effect technology in said communicating step with said end user;

accepting changes in operating conditions from said end user via said user interface;

recording a history of said operating conditions in said microcontroller;

said programming step including running of diagnostic routines to monitor the health of said HVAC system and thereafter taking corrective action based upon severity of any detected health problems;

determining said severity of said detected health problem, said corrective action being preset based on severity of said detected health problems.

8. The method of operating said HVAC system by an end user for room temperature control as recited in claim 7, wherein said programming step includes in an event of power failure, maintaining in memory prior operating conditions so that when power is restored, said HVAC system can return to said prior operating conditions.

9. The method of operating said HVAC system by an end user for room temperature control as recited in claim 8, wherein said detected health problems are included in said communicating step with said end user, said corrective action in order of said severity of said health condition being detected can include (a) logging the event, (b) continuously indicate service required (c) flash service required or (d) shut down HVAC system.

10. The method of operating said HVAC system by an end user for room temperature control as recited in claim 9, wherein said programming step includes prioritizing of maintenance to be performed.

11. The method of operating said HVAC system by an end user for room temperature control as recited in claim 7, wherein said accepting changes step in said operating conditions include desires of said end user being made known in said communicating step via said user interface, said user interface providing for changes in (a) set indoor temperature, (b) variations between ON and OFF conditions (c) mode of operation, and (d) schedule of preselected operating conditions.

12. The method of operating said HVAC system by an end user for room temperature control as recited in claim 11, wherein said schedule is set by said end user and may be changed by said end user via said user interface.

13. The method of operating said HVAC system by an end user for room temperature control as recited in claim 7, wherein said HVAC system may be updated by remote access to said microcontroller, said programming step being rerun during said updates.

14. The method of operating said HVAC system by an end user for room temperature control as recited in claim 7, wherein said programming step being set to vary pulse width of said outputs.