DUAL-SOURCE INTAKE AIR-CONDITIONING SYSTEMS

Abstract

Methods and systems for drawing air from different sources into an air-conditioner or an air-conditioning (AC) system based on control logic and to use condensate water formed on an evaporator to improve the heat rejection of a condenser coil, thereby improving energy efficiency, are described. Some implementations may include a configurable internal ducting system configured to draw air from at least one of an indoor source or an outdoor source. In some implementations, the air-conditioning system may include a control logic to determine whether the air is to be drawn from the indoor source or the outdoor source.

In some implementations, the air-conditioning system may include an evaporator condensate reservoir to store condensate water collected from one or more evaporator coils of the air-conditioning system and an evaporator condensate pump to spray the stored condensate water on one or more condenser coils of the air-conditioning system.

Claims

1. An air-conditioning system comprising: a configurable internal ducting system, wherein the configurable internal ducting system can be configured to draw air from at least one of an indoor source or an outdoor source; and a control logic to determine whether the air is to be drawn from the indoor source or the outdoor source.

2. The air-conditioning system of claim 1, wherein the control logic is configured to reduce energy consumption of the air-conditioning system.

3. The air-conditioning system of claim 1, wherein the control logic causes the air to be drawn from the indoor source when indoor air from the indoor source is cooler than outdoor air from the outdoor source.

4. The air-conditioning system of claim 1, wherein the control logic causes the air to be drawn from the outdoor source when outdoor air from the outdoor source is cooler than indoor air from the indoor source.

5. The air-conditioning system of claim 1, further comprising: an evaporator, wherein the air is drawn from at least one of the indoor source or the outdoor source through the evaporator.

6. The air-conditioning system of claim 1, further comprising: an interior intake fan, wherein the air from the indoor source is recirculated through the interior intake fan; and an exterior intake fan, wherein the air from the outdoor source is circulated through the exterior intake fan.

7. The air-conditioning system of claim 1, further comprising: an interior intake fan, wherein the air from the indoor source is vented out through the interior intake fan.

8. The air-conditioning system of claim 1, further comprising: a single motor to operate an interior fan and an exterior fan, wherein the configurable internal ducting system includes a single moveable plate that controls an intake air source and is moveable to select an interior air source or an exterior air source.

9. An air-conditioning system comprising: an evaporator condensate reservoir to store condensate water collected from one or more evaporator coils of the air-conditioning system; an evaporator condensate pump to spray the stored condensate water on one or more condenser coils of the air-conditioning system; and a control logic configured to control the air-conditioning system.

10. The air-conditioning system of claim 9, wherein the control logic determines whether the evaporator condensate reservoir is full.

11. The air-conditioning system of claim 9, wherein the control logic determines a time during which the evaporator condensate pump should be in operation.

12. The air-conditioning system of claim 9, wherein the control logic determines a duration for which the evaporator condensate pump should be in operation.

13. The air-conditioning system of claim 9, further comprising: a configurable internal ducting system, wherein the configurable internal ducting system can be configured to draw air from at least one of an indoor source or an outdoor source; and an evaporator, wherein the air is drawn from at least one of the indoor source or the outdoor source via the configurable internal ducting system through the evaporator, wherein the control logic is further configured to determine whether the air is to be drawn from the indoor source or the outdoor source.

14. The air-conditioning system of claim 13, wherein the control logic determines whether a temperature of the air from the outdoor source is below a predetermined threshold.

15. The air-conditioning system of claim 13, further comprising: an interior intake fan, wherein the air from the indoor source is recirculated through the interior intake fan.

16. The air-conditioning system of claim 13, further comprising: an interior intake fan, wherein the air from the indoor source is vented out through the interior intake fan.

17. The air-conditioning system of claim 13, further comprising: an exterior intake fan, wherein the air from the outdoor source is circulated through the exterior intake fan.

18. The air-conditioning system of claim 13, wherein the control logic causes the air to be drawn from the indoor source when indoor air from the indoor source is cooler than outdoor air from the outdoor source.

19. The air-conditioning system of claim 9, wherein the control logic causes the air to be drawn from an outdoor source when outdoor air from the outdoor source is cooler than indoor air from an indoor source.

20. An air-conditioning system comprising: a configurable internal ducting system, wherein the configurable internal ducting system can be configured to draw air from at least one of an indoor source or an outdoor source; an evaporator condensate reservoir to store condensate water collected from one or more evaporator coils of the air-conditioning system; an evaporator condensate pump to spray the stored condensate water on one or more condenser coils of the air-conditioning system; and a control logic to determine, based on a selection of a user, whether the air is to be drawn from the indoor source or the outdoor source.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the drawings, like reference numerals designate identical or corresponding parts throughout the several views. Further, as used herein, the words “a,” “an,” and the like generally carry a meaning of “one or more,” unless stated otherwise. The drawings are generally not drawn to scale unless specified otherwise or illustrating schematic structures or flowcharts. A more complete appreciation of this disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

[0019] FIG. 1 shows an example graph of outdoor and indoor air temperature cycles of an example day in an example location in accordance with some implementations;

[0020] FIG. 2 shows a diagram of an exemplary air-conditioning system in accordance with some implementations;

[0021] FIG. 3 shows a diagram of an exemplary evaporator condensate water collection, pumping, and spraying system in accordance with some implementations;

[0022] FIG. 4 shows an example graph for determining spray timing logic in accordance with some implementations;

[0023] FIG. 5 shows an example block diagram for intake air source ducting control logic in accordance with some implementations;

[0024] FIG. 6 shows an example configuration for Mode 1 in accordance with some implementations;

[0025] FIG. 7 shows an example configuration for Mode 2 in accordance with some implementations;

[0026] FIG. 8 shows an example block diagram for spray control logic in accordance with some implementations;

[0027] FIG. 9 shows an example configuration having a single motor and a single moveable airflow control plate in accordance with some implementations; and

[0028] FIGS. 10A and 10B show details of Mode 1 and Mode 2 settings of the single moveable plate in accordance with some implementations.

DETAILED DESCRIPTION

[0029] To introduce energy savings, an air-conditioning system (or heat pump or other compression cycle-based HVAC or other apparatus) may include a ducting system that is configured to draw air from either an indoor or an outdoor source. Such air may be drawn through an evaporator coil. The decision on whether to draw the air from the indoor source or the outdoor source may be based on the respective temperatures of the indoor and the outdoor air. The temperatures may be measured using sensors. Valves may be used to switch positions in order to draw the air from the most appropriate energy-efficient source.

[0030] During the air-cooling process of an air-conditioning system, the dew point of air passing through an evaporator coil drops and the air loses its humidity, thereby resulting in condensate water forming on the coil. Traditional self-contained air-conditioning systems, e.g., through-wall units, discard/eject the condensate water from the system to direct the condensate water away from the air-conditioning system onto the ground or drain.

[0031] Discarding condensate water is a lost opportunity for increasing the energy efficiency of an air-conditioning system. Instead of discarding the condensate water, such water may be collected and stored in a reservoir. This condensate water may be used during peak load conditions, for example, during the conditions shown in Area I of FIG. 1. During such peak load conditions, the water may be sprayed under pressure onto a condenser coil to increase heat rejection and reduce the energy required to provide cooling during peak load conditions.

[0032] FIG. 1 is an example graph of outdoor and indoor air temperature cycles of an example day in an example location in accordance with some implementations. This example graph of outdoor and indoor air temperature cycles shows opportunities for energy savings by using different air intake paths based on indoor and outdoor temperatures at a given point of time. The graph shown in FIG. 1 includes cross-over points where outdoor air temperature is then below indoor air temperature (102) as well as where the outdoor air temperature is then above the indoor air temperature (104). Area I in FIG. 1 represents conditions where recirculating the indoor air is the most energy-efficient source of air for cooling by the air-conditioning system. Area II in FIG. 1 represents conditions where the outdoor air is the most energy-efficient source of air for cooling by the air-conditioning system. This control logic thereby improves energy savings.

[0033] FIG. 2 shows a diagram of an exemplary air-conditioning system in accordance with some implementations. More specifically, FIG. 2 shows the components of an exemplary self-contained air conditioner with configurable air intake source for drawing indoor and outdoor air with the goal of improving energy savings. This exemplary air-conditioning system is a through-wall unit that is positioned through an exterior wall (202) separating the indoor space and the outdoor space, and thus, the indoor and the outdoor sources of air.

[0034] FIG. 2 also shows a ducting system within the air-conditioning system, which ducting system can be configured to draw either indoor air or outdoor air through an evaporator (220). The intake source of air may be selected based on temperature of indoor and outdoor air. Temperature may be measured, for example, using one or more temperature sensors.

[0035] FIG. 2 further shows interior air diverter valve (206) and exterior intake valve (212). The control logic of an exemplary air-conditioning system may configure the positions of the interior air diverter valve (206) and the exterior intake valve (212) so as to draw the intake air from the more energy-efficient source. For example, during daytime hours, the control logic may recirculate indoor air using an interior intake fan (204) and switch off the exterior intake fan (218) to keep out outdoor air. In this case, the interior air diverter valve (206) will be in Position A (208) to keep the indoor air within the air-conditioning system and the exterior intake valve (212) will be in Position 2 (216) to keep the outdoor air out of the air-conditioning system.

[0036] Alternatively, during evening hours, when the temperature of the outdoor air falls below the temperature of the indoor air (102), the control logic reconfigures the interior air diverter valve (206) to Position B (210) and uses the interior intake fan (204) to vent warmer indoor air outside. In this situation, the control logic reconfigures the exterior intake valve (212) to Position 1 (214) and also switches on the exterior intake fan (218) to draw in the outdoor air.

[0037] However, when the temperature of the outdoor air rises above the temperature of the indoor air (104), the control logic reconfigures the interior air diverter valve (206) to Position A (208) and the exterior intake valve (212) to Position 2 (216). In this situation, the control logic also switches off the exterior intake fan (218) in order to keep the outdoor air out of the system.

[0038] FIG. 3 shows an example evaporator condensate water collection, pumping, and spraying system in accordance with some implementations. FIG. 3 shows condensation of water due to air passing through an evaporator (302), as the air cools and loses humidity, water condensates on the evaporator (302). This condensate water can be collected (308) and stored in a condensation water reservoir (310). The condensate water stored can be used during peak load conditions shown in Area I of FIG. 1. During peak load conditions, a water pump (312) may be activated to spray water under pressure through a water spray nozzle (316) onto a condenser (304) to increase the heat rejection of the condenser (304) and reduce the energy required to cool the air within the air-conditioning system under such peak load conditions. FIG. 3 also shows an AC compressor (306) of an air-conditioning system and a condensation collector (308) to collect condensate water into the condensation water reservoir (310).

[0039] FIG. 4 shows an example graph for determining spray timing logic in accordance with some implementations. More specifically, FIG. 4 shows how to determine a time during a day or a night when a condensate water spraying system should be activated. For example, such time may be determined through a spray logic (816) outlined in FIG. 8 (discussed below). The spray logic (816) may set/reset a clock based on the previous day's “maximum daily outdoor temperature” (402) to predict a time in the future corresponding to “condenser water spray optimal use” (404), when/where energy savings may be improved the most or optimized.

[0040] FIG. 5 shows an example block diagram for intake source air ducting control logic in accordance with some implementations. More specifically, FIG. 5 shows an example control logic block diagram for determining position of air diverter valves (206) and (212) and activation of intake fans (204) and (218) based on readings from indoor temperature sensor, Tin (560) and outdoor temperature sensor, Tout (561) as recorded (520).

[0041] In some implementations, a user of an exemplary air-conditioning (AC) system may select (504) from one of four modes—a Normal Air-conditioning Mode (512), an ECO Air-conditioning Mode (518), a Recirculate Air Mode (506), and a Fresh Air Mode (540).

[0042] In some implementations, in the Normal Air-conditioning Mode (512), the exemplary air-conditioning system will operate as a conventional air-conditioning unit, where the air diverter valves (206) and (212) are configured in Position A (208) and Position 2 (216) respectively, i.e., in Mode 2 (514). In this mode, the AC compressor (224) of the AC system is switched on (516).

[0043] In some implementations, in the Recirculate Air Mode (506), the ducting is configured in Mode 2 (508) with the air diverter valves (206) and (212) configured in Position A (208) and Position 2 (216) respectively. In this mode, the compressor (224) of the AC system is switched off (510) and the indoor air is recirculated using the interior intake fan (204), which is switched on. Also, in this mode, the exterior intake fan (218) is switched off to keep the outdoor air out.

[0044] In some implementations, in the Fresh Air Mode (540), the ducting is configured in Mode 1 (542), with the air diverter valves (206) and (212) configured in Position B (210) and Position 1 (214) respectively. In this mode, the compressor (224) of the AC system is switched off (544). Also, the interior intake fan (204) is switched on to vent out the indoor air (to the outside) and the exterior intake fan (218) is switched on to draw in the fresh exterior air (from the outside).

[0045] In some implementations, in the ECO Air-Conditioning Mode (518), the control logic is enabled to dynamically select the most energy-efficient method and configuration to cool the air based on changes in environmental conditions. This mode configures the positions of the air diverter valves (206) and (212) automatically, without a user's intervention, and determines the most energy-efficient configuration using recorded sensor data (520).

[0046] In some implementations of the ECO Air-Conditioning Mode (518), in the first logic processing loop, when a loop counter equals 0 or zero (522), the control logic will proceed to determine whether the outdoor temperature “Tout” (561) is greater than the indoor temperature “Tin” (560) during its process (524). If “Tout” (561) is less than “Tin” (560), a result of “NO” configures the ducting to Mode 1 (526), turns the compressor (224) of the AC system on (528), and adds 1 to the loop counter (530). If “Tout” (561) is greater than “Tin” (560), a result of “YES” configures the ducting to Mode 2 (532), turns the compressor (224) of the AC system on (534), and adds 1 to the loop counter (536).

[0047] In some implementations of the ECO Air-Conditioning Mode (518), loopcount (522) may not equal 0 and a determination of “NO” may occur if it is not the first loop in the logic processing. The purpose of this branch is to include hysteresis in the control logic to avoid excessive changing between Mode 1 and Mode 2, when “Tout” (561) fluctuates within a range of “Tin” (560), where the range is determined by the hysteresis value. In some implementations, if the answer to whether Mode=1 (538) in this branch is “YES”, a determination of whether “Tout” (561)>“Tin” (560)+hysteresis value (548) is made. If the result of this determination is “YES”, then the ducting is configured to Mode 2 (550) and the compressor (224) of the AC system is turned on (552). If the determination of whether “Tout” (561)>“Tin” (560) +hysteresis value (548) results in “NO”, then the branch terminates at “END” (558) and a new loop commences at “START” (502).

[0048] On the other hand, in some implementations, if the first component of this branch determines that the answer to whether Mode=1 (538) is “NO”, a determination of whether “Tout” (561)<“Tin” (560)—hysteresis value (546) is made. If the result of this determination is “YES”, then the ducting is configured to Mode 1 (554) and the compressor (224) of the AC system is turned on (556). If the determination of whether “Tout” (561)<“Tin” (560)—hysteresis value (546) results in “NO”, then the branch terminates at “END” (558) and a new loop begins at “START” (502).

[0049] FIG. 6 shows the configuration of Mode 1, where the interior air diverter valve is in Position B (open intake flap), the interior intake fan is on, the exterior intake valve is in Position 1, and the exterior intake fan is on. FIG. 7 shows the configuration of Mode 2, where the interior air diverter valve is in Position A (close intake flap) and the interior intake fan is on, and where the exterior intake valve is in Position 2 and the exterior intake fan is off.

[0050] FIG. 8 is an example block diagram of spray control logic in accordance with some implementations. More specifically, the logic block diagram shown in FIG. 8 determines whether and when to activate the water condensate spray system. For example, the control logic in FIG. 8 determines when to spray water safely and optimally. Beginning at “START” (802), the spray control logic proceeds to record the current “Tout” (561) and “Tcondenser” (562) values (812), where “Tcondenser” (562) refers to the temperature of a condenser (304). The spray control logic then proceeds to store a series of “Tout” (561) values over time to determine “Tout Max”, the maximum temperature that was achieved during a day and a time when that maximum temperature was achieved (814). The spray control logic then re/sets a specified clock value based on the time when the maximum temperature was reached (814).

[0051] The spray control logic then proceeds to determine whether the spray feature is enabled or not (804). If the feature is not enabled, leading to a “NO” result, the control logic will proceed to “END” (818). If the spray feature is found to be enabled, leading to a “YES” result, the spray control logic proceeds to undertake a systems and function check (806) to look/search for errors before activating the spraying of water. For example, outdoor sensor limits, condenser temperature (562), water pump (312) resistance and condensation water reservoir (310) sensors are checked in this systems and function check (806). If any errors are found, the errors are recorded (808) and the control logic proceeds to “END” (818). If no errors are found, then the spray control logic proceeds to determine whether the outdoor temperature, “Tout” (561), is below a minimum ambient temperature, “Tamb Min”, to safely pump water (810). In some implementations, this check is performed to ensure that the sprayed water does not freeze if freezing conditions prevail. If the outdoor temperature, “Tout” (561), is below a minimum ambient temperature, “Tamb Min”, leading to a “YES” result, the control logic will proceed to “END” (818) and terminate.

[0052] The stored clock reset value (814) is then used by the spray control logic (816) to determine the most beneficial time to spray water on a condenser (304) so as to improve, maximize, or optimize the disclosed air-conditioning system's energy efficiency and/or savings. The spray logic system's output (816) determines the most beneficial time during a day or a night to safely activate the system and spray water (316) on a condenser (304). This output is based on whether the spray feature is enabled or not, the condenser temperature, “Tcondenser” (562), the clock setting based on a time corresponding to the maximum temperature reached during a day as shown in FIG. 4, the level of water in the condensate water reservoir (310), a time corresponding to the last activation of the spray pump, and any errors stored during the systems and function check (808). All these inputs are used to determine whether and when to activate a water pump (312) to spray water on a condenser (304) via a water spray nozzle (316).

[0053] In some implementations, the optimal time at which the water spray system must be activated (316) is determined through a spray control logic process outlined in FIG. 8 above. In some implementations, the spray logic system (816) may reset/set a clock based on a previous day's highest outdoor temperature (402) to determine a time when a likely maximum energy saving may occur in the future (404). Exceptions to the control logic may occur if a systems and function check (806) reveals that one or more errors, e.g., hardware issues, are active (808), if the outdoor temperature is below a pre-determined minimum ambient temperature (810), e.g., if outdoor freezing conditions may freeze the water sprayed, or if condensation water reservoir (310) is near full capacity and water needs to be sprayed to avoid water overflow.

[0054] In some implementations, during peak daytime hours, indoor air is recirculated by turning on an interior intake fan (204), configuring interior air diverter valve (206) in Position A (208) and exterior intake valve (212) in Position 2 (216), and turning off an exterior intake fan (218). In some implementations, during evening hours, when the outdoor air temperature falls below the indoor air temperature (102), interior air diverter valve (206) is configured in Position B (210) to vent warm indoor air to the outside. In this scenario, exterior intake valve (212) is configured in Position 1 (214), and the exterior intake fan (218) is turned on to draw in cool outdoor air via the evaporator (220). In some implementations, once the outdoor air temperature rises above the indoor air temperature (104), interior air diverter valve (206) is configured in Position A (208) and exterior intake valve (212) in Position 2 (216), and the exterior intake fan (218) is turned off. In this case, the interior intake fan (204) is switched on to draw indoor air via the evaporator (220).

[0055] In some implementations, the control logic for determining whether to draw air into an air-conditioning system from an indoor air source or an outdoor air source is based on user selection or options selected by a user. In some implementations, whether and when to spray condensate water on a condenser (304) is based on user selection or options selected by a user.

[0056] In some implementations, the control logic determines the duration for which water may be sprayed on a condenser (304) from the condensation water reservoir (310). In other implementations, a user may determine the duration for which such water may be sprayed.

[0057] FIG. 9 shows an example configuration (900) having a single motor (902) and a single moveable airflow control plate (904) in accordance with some implementations. The single motor (902) controls both an interior airflow fan and an exterior airflow fan. The moveable airflow control plate (904) is moveable between a first position and second position for Mode 1 and Mode 2 operation, respectively. The moveable airflow control plate (904) can also be set to intermediate positions having a mix of interior and exterior air intake.

[0058] FIGS. 10A and 10B show details of Mode 1 and Mode 2 settings of the single moveable plate in accordance with some implementations. FIG. 10A shows details of Mode 1 where the moveable airflow control plate is in a first position that permits exterior air to be drawn in. FIG. 10B shows details of Mode 2 where the airflow control plate is move to a second position that blocks exterior air and permits interior air to flow.

[0059] It will also be appreciated that the interior intake fans, interior air diverter valves, exterior intake fans, exterior intake valves, condensation collectors, condensation water reservoirs, water pumps, water spray nozzles, condensers, evaporators, compressors, intake flaps, temperature sensors, control logic, air-conditioners, and air-conditioning systems described herein are for illustration purposes only and not intended to be limiting. Other types of interior intake fans, interior air diverter valves, exterior intake fans, exterior intake valves, condensation collectors, condensation water reservoirs, water pumps, water spray nozzles, condensers, evaporators, compressors, intake flaps, temperature sensors, control logic, air-conditioners, and air-conditioning systems may or can be used depending on a contemplated implementation.

[0060] It is therefore apparent that there is provided, in accordance with the various example implementations disclosed herein, methods and systems relating to dual-source air intake air-conditioners and methods and systems for using condensate water to boost energy efficiency.

[0061] While some example implementations have been described in terms of a general embodiment with several specific example modifications, it is recognized that other modifications, implementations, and variations of the embodiments described above are within the spirit and scope of the disclosed subject matter. Applicant intends to embrace any and all such modifications, variations, embodiments, and implementations in this application.