US20120222439A1 - System control for air conditioning system - Google Patents

Abstract

A system control to monitor and control the operation of an air conditioning system including at least one evaporator/air handler unit operatively coupled to a compressor/condenser unit comprising a sensor to monitor the operation of the evaporator and to generate a control signal when a predetermined condition within the air conditioning system is sensed and a control unit including logic or circuitry to receive the condensate signal and to deactivate the evaporator/air handler unit and the compressor/condenser unit in response to the control signal.

Description

CROSS-REFERENCE
• This application claims priority as a continuation-in-part application of patent application Ser. No. 12/931,130 filed Jan. 25, 2011 that is a continuation-in-part application of patent application Ser. No. 12/806,977 filed Aug. 25, 2010.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• A system control to monitor and selectively control the operation of an air conditioning system.
• 2. Description of the Prior Art
• Air handling systems such as air conditioning systems typically have a condensate collector or drain pan to collect condensate.
• Often removal of the condensate requires pumping the condensate from the condensation drain pan. Commonly, a drain pan system includes a sensor placed in the drain pan to measure the level of the condensation therein. When the condensate level reaches a predetermined level, the sensor generates a signal sent to a sensor switching circuit to activate the pump or stop operation of the compressor.
• HVAC systems known as mini-split systems present a particularly troublesome challenge. Such systems comprise of two basic units—a compressor and multiple air handlers. The air handler is typically mounted on the wall in the space to be cooled. These air handlers are designed to be compact resulting in limited space for an overflow switch and condensate sensor. Specifically, systems use refrigerant lines together power and control wiring to connect the outdoor compressor to the individual indoor air handlers. The technology, developed in the 1950s, is called split-ductless or mini-split and is the primary method for conditioning spaces within a home or commercial building in countries around the world. These systems allow each space with an indoor air-handler unit to be controlled independently from other rooms, thus providing individualized comfort control within a home.
• In such systems, the compressor is connected to existing house voltage and supplies voltage to the air handlers.
• In addition, a communications link is used to coordinate the operation of the two basic units. As a result, any electronics that would utilize the power supply has the potential of disrupting the communication link. Thus, any effort to provide a condensate removal system would require an electrically isolated battery powered system.
• In order to shut down the highly integrated electro-mechanical system, a condensate control system can be tapped into a commonly found thermistor used to measure the evaporator temperature or the communication link or line forming part of mini-split control loop. As designed, if the thermistor or communication link or line is broken or indicates a bad reading the compressor is shut down. This thermistor can be used to open the circuit when excess condensate is sensed in the condensate collector or drain pan to shut down the compressor.
SUMMARY OF THE INVENTION
• The present invention relates to a system control to monitor and control the operation of an air conditioning system comprising an evaporator/air handler unit coupled in closed-loop fluid communication with a compressor/condenser unit by refrigerant lines or conduits and a condensate collector or drain pan disposed to collect condensate from the evaporator.
• The system control comprises a condensate sensor disposed to sense when condensate within the condensate collector or drain pan reaches a predetermined level and a control unit operatively coupled to the condensate sensor and the air conditioning system to deactivate the compressor/condenser unit and evaporator/air handler unit when condensate reaches the predetermined level within the condensate collector or drain pan for a predetermined period of time by creating a discontinuity or open circuit between the compressor/condenser unit and the evaporator/air handler unit.
• The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• For a fuller understanding of the nature and object of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:
• FIG. 1 is a block diagram of the control system of the present invention in combination with an air conditioning system.
• FIG. 2 is an exploded view of the control system of the present invention.
• FIG. 3 is a detailed view of the coupling harness of the control system of the present invention.
• FIG. 4 is a circuit diagram or schematic of the control system of the present invention.
• FIG. 5 is a circuit diagram or schematic of a control system of an alternate embodiment of the present invention.
• FIG. 6 is a detailed view of an alternate embodiment of the coupling harness of the control system of the present invention.
• FIG. 7 is a block diagram of a control system of another alternate embodiment of the present invention in combination with an air conditioning system.
• FIG. 8 is a partial circuit diagram or schematic of the control system of the alternate embodiment of the present invention depicted inFIG. 7.
• FIG. 9 is a partial circuit diagram or schematic of the control switch assembly of the control system of the alternate embodiment of the present invention depicted inFIGS. 7 and 8.
• Similar reference characters refer to similar parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
• The present invention relates to a system control to monitor and selectively control the operation of an air conditioning system that includes a compressor10 and anair handler12 including anevaporator14.
• As shown inFIG. 1, theair handler12 andevaporator14 are coupled in closed-loop fluid communication with the compressor10 by refrigerant lines orconduits16 and18. A condensate collector ordrain pan20 is disposed to collect condensate from theevaporator14 and acondensate drain22 can direct or carry condensate from the condensate collector ordrain pan14 to a collection or run-off site (not shown). Theair handler12 further includes an air handlerelectronic control system24 coupled to multiple or independent redundant fault sensors orthermistors26 and28 disposed in heat exchange relationship relative to theevaporator14. The compressor10 and air handlerelectronic control system24 are operatively coupled together bypower supply line30 and a datacommunication control link31. The fault sensors orthermistors26 or28 monitor the temperature at theevaporator14 and to generate a fault signal fed to the air handlerelectronic control system24 including logic or circuitry to generate a fault control signal in response to the fault signal when an overheat condition is detected at theevaporator14 to be fed over the air handler power or communication conductors orlines30 or31 to stop or turn-off the compressor10 as described more fully hereinafter. The compressor10 is coupled to an external power source (not shown) by a power supply line orconductor32.
• As shown inFIG. 1, the system control of the present invention comprises acondensate sensor34 disposed to sense when condensate collected in the condensate collector ordrain pan20 reaches a predetermined level and to generate a condensate level signal and a control unit generally indicated as36 including logic or circuitry coupled to thecondensate sensor34 by sensor signal conductors orlines38 and40 to receive the condensate level signal from thecondensate sensor34 and to generate a control signal in response thereto. The air handlerelectronic control system24 is coupled directly to the fault sensor orthermistor28 by a firstcontrol signal conductor42. A second control signal conductor comprising afirst segment44A is coupled to thecontrol unit36 and asecond segment44B coupled between thecontrol unit36 and the air handlerelectronic control system24 to cause the fault sensor orthermistor28 to generate a pseudo fault signal fed to the air handlerelectronic control system24 response to the condensate level signal when the condensate level collected in the condensate collector ordrain pan20 reaches the predetermined level to shut-down the compressor10 andevaporator14 as described above.
• As shown inFIGS. 2 and 4, thecondensate sensor34 comprises a first condensate sensing element orprobe46 and a second condensate sensing element orprobe48 coupled or connected to thesystem control device36 that comprises a battery power source, low battery indicator or alarm and control relay or switch generally indicated as50,52 and54 respectively enclosed within a housing and a back plate generally indicated as56 and58 respectively.
• FIG. 3 depicts a coupling harness comprising asensor interface connector60 and an air handler electronic controlsystem interface connector62 connected to the fault sensor orthermistor28 and the air handlerelectronic control system24 byconductors64 and66 and connected to a controldevice interface connector70 coupled between the fault sensor orthermistor28 and the air handlerelectronic control system24 by theconductors42 and44A/44B respectively to operatively integrate or couple thesystem control device36 with the existing air conditioning system without compromising the integrity of the communication andcontrol links30 and31 between theair handler12 andevaporator14, and the compressor10.
• FIG. 4 is a schematic diagram of thesystem control device36 of the present invention comprising the isolated externalbattery power source50, the low battery indicator oralarm52 and the control relay or switch orcircuit54.
• The relay orswitch54 is powered by the isolated externalbattery power source50 connected between a positive voltage socket orconnector110 and a ground or negative voltage socket orconnector112.
• The low battery indicator oralarm52 comprises a buzzer oraudible alarm114 coupled to the output of acomparator116 coupled to the isolated externalbattery power source50 and afixed reference voltage118 to generate a low battery alarm indicator signal when the voltage from the isolated externalbattery power source50 reaches a minimum predetermined voltage such as 2.7 VDC. The low battery indicator oralarm52 further includesscaling resistors120,122 and124,timing resistors126 and128 andtiming diode130,feedback resistors132 and134,capacitor136, andresistor137.
• A positive voltage socket orconnector138 is coupled between the isolated externalbattery power source50 through a current limitingresistor140 and the firstcondensate sensing probe46 through the first sensor signal conductor orline38. A second socket orconnector142 is coupled between the solid state control circuit described hereinafter and the secondcondensate sensing probe48 through the second sensor signal conductor orline40.
• The solid state control circuit or control device comprises an input stage generally indicated as144 coupled to an output stage generally indicated as146 by an intermediate stage generally indicated as148.
• Theinput stage144 comprises a voltage limitingzeneer diode150,resistor152 andfilter capacitor154 combination and aresistor156 to hold the voltage low and configured to receive current through socket orconnector142 when the level of condensate accumulated in the condensate collector ordrain pan20 is such that the tips of firstcondensate sensing probe46 and the secondcondensate sensing probe48 are submersed in the condensate creating an impedance completing the circuit causing current to flow through theinput stage144. Theintermediate control stage148 comprises afield effect transistor158 coupled to the output of theinput stage144 such that when current flows through theinput stage144 thefield effect transistor158 is turned on.
• Theoutput stage146 comprises an outputcontrol signal circuit162 coupled to thecondensate sensor34 through theinput stage144 and theintermediate stage148 and an output controlsignal generator circuit166/168 coupled between theair handler control24 through the fault sensor orthermistor28. More specifically, theoutput stage146 comprises a opto isolator oropto coupler160 including a light emitting diode (LED)162 coupled between positive voltage VCC through aresistor164 and thefield effect transistor158 of theintermediate stage148, and a pair offield effect transistors166 and168 coupled to the fault sensor orthermistor28 and the airhandler control system24 through sockets orconnectors170 and172, control signal conductor orline42 and control signal conductor orline44 such that whenfield effect transistor158 ofintermediate stage148 is conductingLED162 of opto isolator oropto coupler160 is energized driving thefield effect transistors166 and168 to generate the condensate level signal fed to the fault sensor orthermistor28 causing the air handlerelectronic system24 to generate the fault control signal fed to the compressor10 through the air handler power/communications conductors orlines30 and31 shutting down the compressor10 when the condensate level reaches a predetermined level in the condensate collector ordrain pan20 as sensed by the first condensate element or sensingprobe46 and the second condensate sensing element or probe48 thus completing a circuit to actuate the fault sensor orthermistor28.
• The condensate can be drained or pumped from the condensate collector ordrain pan20 through thecondensate drain conduit22.
• FIG. 5 is a schematic diagram of an alternate embodiment of thesystem control device36 comprising abattery power source210, a low battery indicator oralarm212, a control unit generally indicated as214 including amicroprocessor216.
• Thecontrol unit214 including amicroprocessor216 are powered by thebattery power source210 connected between a positive voltage socket orconnector218 and a ground or negative voltage socket orconnector220.
• The low battery indicator oralarm212 also powered by thebattery power source210 comprisesresistors222 and224 forming a voltage divider coupled to an analog to digital convertor (ND converter) within themicroprocessor216 by a conductor orline226 to monitor the battery status or life in combination with an audible orvisual alarm indicator228 coupled to themicroprocessor216 by a conductor orline230.
• Thecontrol unit214 comprises an input stage generally indicated as232 coupled to an output stage generally indicated as234 by themicroprocessor216 or an intermediate stage generally indicated as235.
• The input stage or controlsignal circuit232 comprisesresistors236 and238 coupled to the first condensate sensing element or probe46 and the second condensate sensing element or probe48 respectively by connectors orlines240 and242 and coupled to the ND converter within themicroprocessor216 by a conductor orline244. A voltage limitingzeneer diode246 and a resistor248 are coupled to ground to provide protection to the input stage orsignal control circuit232. When the condensate within the condensate collector ordrain pan20 is below the predetermined level the circuit is open. However when the condensate reaches the predetermined level within the condensate collector ordrain pan20 the condensate creates an impedance between the first condensate sensing element or probe46 and the second condensate sensing element or probe48 presenting a voltage or condensate signal to the ND converter within themicroprocessor216.
• The output stage or control signal generator circuit or controlswitch assembly234 comprises aresettable latching relay250, including adouble pole switch250 and a dualzeneer diode combination254 coupled to themicroprocessor216 by conductors orlines256 and258 operable in one of either of two states depending on the polarity of the last energizing pulse from the input stage or controlsignal circuit232.Sockets260 and262 are coupled to thefault sensor28 and the airhandler control system24 by the conductors orlines42 and44A/44B respectively.
• The audible orvisual alarm228 such as a piezo sounder driven by themicrocontroller216 will generate a low battery indicator or signal when thebattery power source210 reaches a minimum predetermined voltage.
• Acapacitor261 is a timing component used in conjunction with themicrocontroller216.
• Themicroprocessor216 operates on a predetermined sampling cycle such as 1000 ms sampling cycle. Specifically, during each predetermined sampling cycle of 1000 ms themicrocontroller216 performs two (2) separate functions or conversion samplings (factors or parameters) during a predetermined sampling period such as 10 ms to determine if the condensate level within the condensate collector ordrain pan20 has reached the predetermined level and whether or not the charge or voltage of thebattery power source210 has reached the predetermined minimum voltage or charge.
• An impedance between the first condensate sensing element or probe46 and the second condensate sensing element or probe48 is sensed when the condensate level within the condensate collector ordrain pan20 reaches the predetermined condensate level. Both the impedance and the battery voltage level of thebattery power source210 are sampled multiple times during each 10 ms sampling period. For example, each of the two (2) factors or parameters is sampled five (5) times during each 10 ms sampling period. If the respective multiple samples detect that the condensate in the condensate collector ordrain pan20 has reached the predetermined condensate level the impedance completes the circuit to generate the condensate sensor signal fed to themicroprocessor216 that includes logic or circuitry to generate the condensate level control signal fed through the output control signal circuit or controlswitch assembly234 to the airhandler control system24.
• Similarly, if a low battery is detected or sensed during any of the respective multiple samples during a duty cycle, a low battery signal is created to activate the audible orvisual alarm indicator228.
• During the remaining 990 ms of each sampling cycle, thecontrol device214 including themicroprocessor216 is in a deep sleep mode. That is, if condensate is detected the latching relay is pulsed to effect shutdown of the compressor10. When the condensate is removed the latching relay is pulsed to effect normal operation of the compressor10.
• Furthermore, due the pulsed nature of the latching relay power consumption is extremely low, preserving the charge and extending the life of thebattery power source210.
• FIG. 6 depicts an alternate embodiment of the coupling harness comprising a controlsensor interface connector60 and an air handler controlsystem interface connector62 connected to the control sensors orthermistors26 and the airhandler control system24 byconductors64 and66 and connected to thecontrol device36 by theconductors42 and44 to operatively integrate or couple thecontrol system36 with an existing air conditioning system without compromising the integrity of the communication andcontrol links30 and31 between theremote air handler12 and the compressor10.
• FIGS. 7 through 9 show another alternate embodiment of thesystem control device36 of the present invention.
• Overall, the basic components of the alternate embodiment shown inFIG. 7 is similar to the embodiment depicted inFIG. 1 except that the compressor/condenser unit10 is connected to the air handlerelectronic control system24 through thecontrol unit36 by a data communication link orline comprising segments31A and31 B. Otherwise corresponding components are similarly designated.
• FIG. 8 is a partial schematic diagram of an alternate embodiment of thecontrol unit36 ofFIG. 7 comprising abattery power source310, a low battery indicator oralarm312 and a control unit including a microprocessor316.
• The control unit and microprocessor316 are powered by thebattery power source310 connected between a positive voltage and a ground or negative voltage.
• The low battery indicator oralarm312 also powered by thebattery power source310 is coupled to an analog to digital convertor (ND converter) within the microprocessor316 to monitor the battery status or life.
• The control unit is coupled between thecondensate sensor34 and an analog to digital converter (ND converter) within the microprocessor316 by sensor signal conductors orlines38 and40. When condensate within the condensate collector ordrain pan20 is below the predetermined level the circuit between the first condensate sensing element or probe46 and the second sensing element or probe48 is open. However when the condensate reaches the predetermined level within the condensate collector ordrain pan20 the condensate creates an impedance across the first condensate sensing element or probe46 and the second condensate sensing element or probe48 presenting a voltage or condensate signal through thecondensate control input318 to the ND converter within the microprocessor316.
• As shown inFIG. 9, the control unit further comprises acontrol switch assembly320 comprises aresettable latching relay322 including a double throw/double pole switch generally indicated as324 andcoil326 combination, adual zeneer diode328 and a pair ofFET circuits334 and336 arranged in a push/pull configuration operable in one of either of two states depending on the polarity of the last energizing pulse from the microprocessor316 when thecondensate sensor34 detects the presence or absence of condensate in the condensate collector ordrain pan20. Thecontrol switch assembly320 is coupled between the compressor/condenser unit10 and the air handler/evaporator unit12 by the data communication link orlines31A and31B respectively (FIG. 7).
• Theresettable latching relay322 comprises a data communication link control switch including afirst switch member338 movable or positionable between a first or open position and a second or closed position and afirst contact340. The first switch member is connected to the microprocessor316 through the data communication link orsegment31A while thefirst contact340 is connected to the microprocessor316 through the conductor orline31B such that when the first switch member is in the first position the data communication link control switch is in an open circuit configuration and when thefirst switch member338 is in the second or closed position thefirst switch member338 contacts thefirst contact340 such that the data communication link control switch is in a closed circuit configuration connecting data communication links orsegments31A and31B.
• Theresettable latching relay322 further comprises a power supply control switch including asecond switch member342 connected to the microprocessor316 through the conductor orline44B movable or positionable between a first or open position and a second or closed position and asecond contact344 connected to the microprocessor316 through the conductor orline44A such that when thesecond switch member342 is in the first or open position the power supply control switch is in an open circuit configuration and when thesecond switch member342 is in the second or closed position thesecond switch member342 contacts thesecond contact344 such that the data communication link control switch is in a closed circuit configuration connectingpower supply lines44A and44B.
• The audible orvisual alarm312 such as a piezo sounder driven by the microcontroller316 will generate a low battery indicator or signal when thebattery power source310 reaches a predetermined voltage. The use of a battery powered system eliminates the need to incorporate high voltage electronics components in the circuitry to step-down the AC voltage and convert the AC voltage to Low-DC voltage. The system control operates independent of the air condition system.
• Acapacitor346 is a timing component used in conjunction with the microcontroller316.
• The microprocessor316 operates on a predetermined sampling cycle such as 1000 ms sampling cycle. The microprocessor316 further includes a state of the art clock or timing component for the sampling. Specifically, during each predetermined sampling cycle of 1000 ms the microcontroller316 performs two (2) separate functions or conversion samplings (factors or parameters) during a predetermined sampling period such as 10 ms to determine if the condensate level within the condensate collector ordrain pan20 has reached the predetermined level and whether or not the charge or voltage of thebattery power source310 has reached either of two predetermined voltage or charge levels.
• An impedance between or across the first condensate sensing element or probe46 and the second condensate sensing element or probe48 is detected when the condensate level within the condensate collector ordrain pan20 reaches the predetermined condensate level. Both the impedance and the battery voltage level of thebattery power source310 are sampled multiple times during each 10 ms sampling period. For example, each of the two (2) factors or parameters is sampled five (5) times during each 10 ms sampling period. If the respective multiple samples detect that the condensate in the condensate collector ordrain pan20 has reached the predetermined condensate level the impedance completes the circuit to generate the condensate sensor signal fed to the microprocessor316 that includes logic or circuitry to generate the condensate level control signal fed through the output control signal circuit or controlswitch assembly320 to the airhandler control system24.
• Similarly, if a low battery such as 2.7 VDC is detected or sensed during any of the respective multiple samples during a duty cycle, a low battery signal is generated to activate the audible orvisual alarm indicator312. In addition, when the voltage or charge reaches a second predetermined level such as 2.4 VDC to 2.5 VDC, the microprocessor316 will generate a shut-down signal to completely shut down the compressor/condenser unit10 and the evaporator/airhandler control unit12/14.
• During the remaining 990 ms of each sampling cycle, the control device314 including the microprocessor316 is in a deep sleep mode. That is, if condensate is detected the latching relay is pulsed to effect shutdown of the compressor10. When the condensate is removed the latching relay is pulsed to effect or return normal operation of the compressor10.
• More particularly, when condensate in the condensate collector ordrain pan20 reaches a predetermined level thecondensate microsensor34 generates a condensate signal sent to the microprocessor316 to initiate a clock or count-down of a predetermined period of time such as 15-20 seconds.
• If the condensate signal is continuous for the predetermined period of time, the microprocessor316 generates a control signal fed to thecontrol switch assembly320 of thecontrol unit334 causing thecontrol device334 to transition from the first state to the second state repositioning the first switch means338 from the closed or contact position to the position by the action of thecoil326 creating a discontinuity or open circuit between the evaporator/air handler unit12/14 and the compressor/condenser unit10 to shut down the air conditioning system.
• Specifically, the data communication link control switch will “Open” breaking the connection data communication line or link between data communication links orlines segments31A and31B. Thecoil326 moves the double throw/double pole switch324 of the resettable latching relay from the closed/contact position to the second/noncontact position between the evaporator/air handling unit12/14 and causing both units to shut down.
• After the air conditioning system has shut down, thecondensate sensor34 will continue to monitor condensate in the condensate collector ordrain pan20. When condensate in the condensate collector ordrain pan20 is no longer detected by thecondensate sensor34, a second or no-condensate signal is sent to the microprocessor316 to initiate a clock or count-down of a second predetermined period of time such as 6-10 seconds.
• If the no-condensate signal is continuous for the second period of time, the microprocessor316 generates a second control signal fed to the control device causes the control device to transition from the second state to the first state completing the circuitry or electrical path, that is,communication link31A and31B between the evaporator/air handler unit12/14 and the compressor/condenser unit10 restoring operation of the air handling system.
• In other words, the microprocessor316 will generate a de-energize or reset latching signal closing the data communication link control switch reconnecting the datacommunication line segments31A and31B restoring normal operation of the air conditioning system.
• Due to the pulsed nature of the latching relay power consumption is extremely low, preserving the charge and extending the life of thebattery power source310.
• Alternately, both the data communication link control switch and the power supply control switch of thecontrol switch assembly320 of thecontrol unit36 may be coupled data communication line orlink segments31A and31B andpower line segments44A and44B. In this configuration, both the power supply line and data communication line or link act in parallel to control operation of the system control and thus the air condition system.
• It will thus be seen that the objects set forth above, among those made apparent from the preceding description are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.
• It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Claims (13)

1. A system control to monitor and control the operation of an air conditioning system comprising an evaporator/air handler unit coupled in closed-loop fluid communication with a compressor/condenser unit by refrigerant lines or conduits and a condensate collector disposed to collect condensate from the evaporator and operatively coupled by a power supply line and a data communication link, said system control comprises a condensate sensor disposed to sense when condensate within the condensate collector reaches a predetermined level and a control unit operatively coupled to said condensate sensor and the air conditioning system to deactivate the compressor/condenser unit and evaporator/air handler unit when condensate reaches the predetermined level within the condensate collector for a predetermined period of time by creating a discontinuity or open circuit between the compressor/condenser unit and the evaporator/air handler unit.

2. The system control ofclaim 1 wherein said control unit comprises a battery power source and a microprocessor powered by said battery power source.

3. The system control ofclaim 2 further includes a low battery indicator powered by said battery power coupled to said microprocessor to monitor the battery status or life.

4. The system control ofclaim 3 wherein a predetermined battery voltage is detected when a low battery signal is generated to activate an alarm indicator.

5. The system control ofclaim 4 wherein when a second predetermined battery voltage is detected said microprocessor will generate a shut-down signal to completely shut down the compressor/condenser unit and the evaporator/air handler control unit.

6. The system control ofclaim 2 wherein said control unit is coupled between said condensate sensor comprising a first condensate sensing element and a second condensate sensing element and said microprocessor by a pair of sensor signal conductors such that when condensate within condensate collector is below the predetermined level the circuit between said first condensate sensing element and said second condensate sensing element is open and when the condensate reaches the predetermined level within the condensate collector the condensate creates an impedance across said first condensate sensing element and said second condensate sensing element generating a condensate signal through said condensate control to said microprocessor.

7. The system control ofclaim 2 wherein said control unit comprises a control switch assembly is coupled between the compressor/condenser unit and the air handler/evaporator unit by the data communication link.

8. The system control ofclaim 7 wherein said control switch assembly comprises a data communication link control switch including a first switch member movable or positionable between a first position or state and a second position or state and a first contact, said first switch member connected to said microprocessor through a data communication link segment while said first contact is connected to said microprocessor through a second data communication link segment such that when said first switch member is in said first position the data communication link control switch is in an open circuit configuration to deactivate the air conditioning system and when the said switch member is in said second position said switch member contacts said first contact such that the data communication link control switch is in a closed circuit configuration connecting data communication link segments to operate the air conditioning system.

9. The control unit ofclaim 8 wherein said control switch assembly further comprises a power supply control switch including a second switch member connected to said microprocessor movable or positionable between a first position and a second position and a second contact connected to said microprocessor through such that when said second switch member is in said first position said power supply control switch is in an open circuit configuration and when said second switch member is in the second position said second switch member contacts said second contact such that the power supply line is in a closed circuit configuration connecting power supply lines to operate the air conditioning system.

10. The system control ofclaim 8 wherein said condensate sensor generates a condensate signal sent to said microprocessor to initiate a clock or count-down of a predetermined period of time and said microprocessors generate a control signal fed to said control switch assembly causing said control device to transition from the first state to the second state repositioning said first switch member from said contact position creating a discontinuity or open circuit in the data communication link between the evaporator/air handler unit and the compressor/condenser unit to shut down the air conditioning system when the condensate signal is present for said predetermined period.

11. The system control ofclaim 10 wherein after the air conditioning system has shut down said condensate sensor continues to monitor condensate in the condensate collector and condensate in the condensate collector is no longer detected by said condensate sensor a second or no-condensate signal is generated and sent to said microprocessor to initiate a clock or clock-down of a second predetermined period of time and if said no-condensate signal is continuous for the second period of time, said microprocessor generates a second control signal fed to the control switch assembly causes said control assembly to transition from said second state to the first state completing the circuitry or electrical path between said data communication segments the evaporator/air handler unit and the compressor/condenser until restoring operation of the air handling system.

12. The system control ofclaim 9 wherein said condensate sensor generates a condensate signal sent to said microprocessor to initiate a clock or count-down of a predetermined period of time and said microprocessors generate a control signal fed to said control switch assembly causing said control device to transition from the first state to the second state repositioning said first switch member from said contact position creating a discontinuity or open circuit in the data communication link between the evaporator/air handler unit and the compressor/condenser unit to shut down the air conditioning system when the condensate signal is present for said predetermined period.

13. The system control ofclaim 12 wherein after the air conditioning system has shut down said condensate sensor continues to monitor condensate in the condensate collector and condensate in the condensate collector is no longer detected by said condensate sensor a second or no-condensate signal is generated and sent to said microprocessor to initiate a clock or clock-down of a second predetermined period of time and if said no-condensate signal is continuous for the second period of time, said microprocessor generates a second control signal fed to the control switch assembly causes said control assembly to transition from said second state to the first state completing the circuitry or electrical path between said data communication segments the evaporator/air handler unit and the compressor/condenser until restoring operation of the air handling system.

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