Timer speedup for servicing an air conditioning unit with an electronic control

• US 4,470,266 A
• Filed: 03/29/1982
• Issued: 09/11/1984
• Est. Priority Date: 03/29/1982
• Status: Expired due to Fees

• Current Assignee: Carrier Corporation (Carrier Global Corporation)
• Original Assignee: Carrier Corporation (Carrier Global Corporation)
• Inventors: Reedy, Wayne R., Briccetti, Mario F.
• Primary Examiner(s): Tanner, Harry
• Application Number:
  US06/362,780
• Time in Patent Office: 897 Days
• Field of Search: 62/155, 62/234, 62/231, 62/157, 62/158, 62/125, 62/126, 236/46 R, 165/12, 165/11 R, 165/29
• US Class Current: 62/126
• CPC Class Codes: F24F 1/0007 Indoor units, e.g. fan coil units self-contained units F24F1/02
• CPC Class Codes: F24F 1/0053 mounted at least partially below the floor; with air distribution below the floor
• 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 11/32 Responding to malfunctions or emergencies
• CPC Class Codes: F24F 11/38 Failure diagnosis
• CPC Class Codes: F24F 11/41 Defrosting; Preventing freezing
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/67 Switching between heating and cooling modes
• CPC Class Codes: F24F 11/72 for controlling the supply of treated air, e.g. its pressure
• CPC Class Codes: F24F 11/86 by controlling compressors within refrigeration or heat pump circuits
• CPC Class Codes: F24F 11/871 by controlling outdoor fans
• CPC Class Codes: F24F 11/88 Electrical aspects, e.g. circuits
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2221/54 Heating and cooling, simultaneously or alternatively
• CPC Class Codes: G05D 23/1917 using digital means

Abstract

An apparatus and method is disclosed for regulating delay periods in the operation of an air conditioning system. A speedup means is provided for a serviceman to speed up the delay intervals to avoid long waiting periods between modes of operation of the air conditioning unit. Means are provided for removing the speedup means after delay periods have occurred to prevent inadvertent operation of the air conditioning system with shortened delay intervals.

Claims

1. A method of operating an air conditioning system incorporating a microcomputer control for controlling operation of the system including switching the air conditioning system between various modes of operation, which comprises the steps of:

delaying operation of the air conditioning system for selected delay time intervals of varying lengths when switching between certain of the various modes of operation of the air conditioning system;

generating a speedup signal when it is desired to decrease the length of a delay time interval;

sensing the occurrence of the speedup signal;

modifying the operation of the air conditioning system to decrease the length of only the first delay time interval extending after the occurrence of the speedup signal is sensed; and

discontinuing the step of modifying when the air conditioning system is switched between modes of operation to return the air conditioning system to normal operation even though further occurrences of the speedup signal are sensed.

2. The method as set forth in claim 1 wherein the step of generating a signal comprises:

connecting two pins of the microcomputer control.

3. The method as set forth in claim 1 wherein the air conditioning unit includes a refrigeration circuit with a compressor and may be operated with a defrost initiation delay, a defrost timer delay, a defrost termination delay and a short cycling delay;

wherein the step of delaying for selected time intervals acts to achieve each delay and wherein the step of discontinuing the step of modifying includes discontinuing when the compressor is energized or de-energized or defrost is initiated or terminated.

4. The method as set forth in claim 1 wherein the microcomputer control includes a clock for emitting periodic pulses, wherein the step of delaying for selected time intervals comprises:

decrementing a delay interval for each delay period at a first rate as a function of the number of clock pulses emitted; and

wherein the step of modifying includes decrementing the delay interval at a second rate faster than the first rate as a function of the number of clock pulses emitted.

5. The method as set forth in claim 1 wherein the step of discontinuing includes:

setting a slow speed indicator when the air conditioning unit switches between operations;

detecting if the slow speed indicator has been set; and

preventing the step of modifying if the slow speed indicator is detected.

6. The method as set forth in claim 5 and further including the step of:

clearing the slow speed indicator when the step of sensing does not detect the speedup signal.

7. Apparatus for operating an air conditioning unit including a refrigeration circuit with a compressor and a microcomputer control which comprises:

means for determining delay periods between various operating sequences of the air conditioning unit;

jumper means for generating a speedup signal;

detection means for determining the occurrence of a speedup signal;

means for modifying the operation of the air conditioning unit to decrease the length of only the first delay period extending after the occurrence of the speedup signal is detected; and

means for returning the air conditioning unit to normal operation when the air conditioning unit is switched between operating sequences even though further occurrences of the speedup signal are detected by the detection means.

8. The apparatus as set forth in claim 7 wherein the microcomputer includes a clock for emitting periodic pulses and wherein the means for determining delay periods detects said pulses and decrements a timer at a predetermined rate in response to said pulses detected.

9. The apparatus as set forth in claim 7 wherein the means for returning the air conditioning unit to normal operation comprises:

means for generating an indicator in response to specific operations of the air conditioning unit; and

override means responsive to the means for generating an indicator to prevent the means for modifying the operation of the air conditioning unit from being energized notwithstanding further occurrences of the speedup signal being detected by the detection means.