Systems and Methods for Heating and Removing Condensation from Air Conditioning Units

FIELD

This disclosure relates generally to air conditioning units and more particularly to systems and methods for heating and removing condensation from air conditioning units.

BACKGROUND

FIG. 1 illustrates an air conditioning unit 100 within a wall 102. The wall 102 separates an indoor space 104 from an outdoor space 106. It should be noted that in some cases, the air conditioning unit 100 may be placed in a window of a wall, as opposed to being disposed in a through-hole in the wall that is designed to hold the air conditioning unit 100. In either case, the air conditioning unit includes an indoor side 108 disposed within the indoor space 104 and an outdoor side 110 disposed in the outdoor space 106. The outdoor side 110 includes vents 112 to expel air 114 from the air conditioning unit.

In a cooling mode, a compressor pumps heated refrigerant to an outdoor heat exchanging coil within the outdoor side 110. The outdoor heat exchanging coil will draw the heat from the heated refrigerant and release the heat to the outdoor space 106 as heated air 114 thus cooling the refrigerant. The cooled refrigerant is then pumped through an expansion device that further cools the refrigerant and then to an indoor heat exchanging coil within the indoor side 108. The indoor heat exchanging coil will draw heat from the indoor space 104, thus cooling the indoor space 104, and transfer the heat to the cooled refrigerant. This cycle continues so long as cooling is needed in the indoor area 104. As the indoor coil contains cold/cooled refrigerant, it dehumidifies the indoor air by extracting moisture. This extracted moisture sheds off the indoor coil and pools into excess condensate. Standard practice for air conditioners of similar type is to then use gravity or a condensate pump to remove this condensate to the outdoor side of the system where that condensate can be “thrown” against the hot outdoor coil to evaporate the water or this condensate pools in the unit basepan and typically drips out of the unit. The cycle is reversed in a heating mode.

In the heating mode, the cycle is reversed. The compressor pumps high temperature high pressure refrigerant into the indoor heat exchanger, which releases heat into the indoor space 104. After which, cooled refrigerant goes into the expansion valve or capillary tube. The refrigerant is further cooled in the expansion valve or capillary tube. Then, this cooled refrigerant cools the outdoor space 106, hence leading to frost formation.

When operating in the heating mode, moisture from air condenses on cold outdoor heat exchanging coil, and frost may form on the outdoor heat exchanging coil. If this frost builds up too much, the efficiency of the air conditioning unit 100 will drop. To avoid this situation, if a predetermined amount of frost is detected, for example by a frost detector, then the air conditioning unit 100 will operate in a defrost mode to melt the frost on the outdoor heat exchanging coil.

In some instances, the melted frost generally drips from the bottom of the air conditioning unit 100. This dripping may irritatingly hit passersby, or the pool of defrosted water in the drain pan of the air conditioning unit 100 would be a source of microbial growth and foul smell. More concerning, however, is when the melted frost turns into an icicle 116 hanging from the bottom of the air conditioning unit. If the icicle 116 breaks off, it may fall, which is undesirable.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is set forth with reference to the accompanying drawings. In some instances, the use of the same reference numerals may indicate similar or identical items. Various embodiments may utilize elements and/or components other than those illustrated in the drawings, and some elements and/or components may not be present in various embodiments. Throughout this disclosure, depending on the context, singular and plural terminology may be used interchangeably.

FIG. 1 illustrates an air conditioning unit.

FIG. 2 illustrates an air conditioning unit in accordance with one or more embodiments of the present disclosure.

FIG. 3 illustrates a method of operating the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 4A illustrates a controller of the air conditioning unit of FIG. 2 at one stage of operation in accordance with one or more embodiments of the present disclosure.

FIG. 4B illustrates the controller of the air conditioning unit of FIG. 2 at a subsequent state of operation in accordance with one or more embodiments of the present disclosure.

FIG. 5A illustrates an oblique view of a sub-base drip pan of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 5B illustrates a side view of the sub-base drip pan of FIG. 5A in accordance with one or more embodiments of the present disclosure.

FIG. 6 illustrates a side view of a portion of an outdoor heat exchanging coil and another sub-base drip pan in accordance with one or more embodiments of the present disclosure.

FIG. 7 illustrates a heating element including a hot refrigerant bypass of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 8A illustrates a first set of timing diagrams of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 8B illustrates a second set of timing diagrams of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 8C illustrates a third set of timing diagrams of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 9 illustrates a side view of a configuration the discharge fan, the outdoor heat exchanging coil, and the vaporizer of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 10 illustrates a side view of a configuration the discharge fan, the outdoor heat exchanging coil, and the vaporizer of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIG. 11 illustrates a front view of a configuration the discharge fan and vaporizers of the air conditioning unit of FIG. 2 in accordance with one or more embodiments of the present disclosure.

FIGS. 12A-12B illustrate a portion of another air conditioning unit.

DETAILED DESCRIPTION

This disclosure relates generally to systems and methods for removing condensate that results from a defrosting operation on an outdoor heat exchanging coil and condensate that results from air moisture condensing on the outdoor heat exchanging coil in an air conditioning unit.

In certain embodiments, an air conditioning unit may include an indoor side and an outdoor side. The outdoor side may include a drip pan disposed below the outdoor heat exchanging coil. When a defrosting operation is performed on the outdoor heat exchanging coil, the resulting condensate is collected by the drip pan. A heating element may be disposed in the drip pan to prevent the condensate from re-freezing while within (e.g., at the bottom of) the drip pan. Further, a condensate pump may be configured to pump the collected heated condensate from the drip pan through a water transport system.

In certain embodiments, the air condition unit additionally includes a vaporizer that is configured to convert the pumped and heated condensate to vapor. In addition, the air conditioning unit may include a discharge fan that is configured to blow the vapor out through the outdoor side and out to the outside area.

Turning now to the drawings, FIG. 2 illustrates an air conditioning unit 200 in accordance with one or more embodiments of the present disclosure. The air conditioning unit 200 includes an indoor side 202 and an outdoor side 204. The indoor side 202 includes an indoor heat exchanging coil 206, a condensate pump 208, a vaporizer 210, and a discharge fan 212. The outdoor side 204 houses an outdoor heat exchanging coil 214, a compressor 216, a valve 217, a perforated plate 218, a sub-base drip pan 220, a water transport system 222, a controller 224, a frost detector 226, and a heating element 228.

The air conditioning unit 200 also includes communication lines 230, 231, 232, 234, 236, 238, and 240. The controller 224 is arranged to (i) communicate with the frost detector 226 via the communication line 230, (ii) communicate with the valve 217 via the communication line 231, (iii) communicate with the compressor 216 via the communication line 232, (iv) communicate with the vaporizer 210 via the communication line 240, (v) communicate with the condensate pump 208 via the communication line 238, (vi) communicate with the heating element with via the communication line 234, and (vii) communicate with the discharge fan 212 via the communication line 236. Any suitable number of communication lines may be used herein.

Additionally included, but not shown for purposes of brevity, are an indoor loop of refrigerant lines between the indoor heat exchanging coil 206, the valve 217, and the compressor 216 and an outdoor loop of refrigerant lines between the outdoor heat exchanging coil 214, the valve 217 and the compressor 216. The valve 217 is a component that is responsible for switching the flow of refrigerant between the compressor 216 and both the indoor coil 206 and the outdoor coil 214. The valve 217 is usually located near the compressor 216 and includes a valve body, a sliding piston, and a solenoid coil.

When the air conditioning unit 200 is in the cooling mode, the valve 217 is in the “cool” position. This means that the refrigerant flows from the compressor 216 to the outdoor coil 214, wherein the outdoor coil 214 is configured to draw the heat from the heated refrigerant and release the heat to the outdoors, thus cooling the refrigerant again. The cooled refrigerant is then pumped through an expansion device to the indoor heat exchanging coil 206. The indoor heat exchanging coil 206 is configured to draw heat from the indoor space, thus cooling the indoor space, and transferring the heat to the cooled refrigerant. This cycle continues so long as cooling is needed in the indoor area.

When the air conditioning unit 200 is in the heating mode, the valve 217 is switched to the “heat” position. This causes the flow of refrigerant to reverse direction. The refrigerant now flows from the compressor 216 to the indoor coil 206, where it releases heat to the indoor air. The refrigerant then flows through an expansion valve and into the outdoor coil 214, wherein the outdoor coil 214 absorbs heat from the outside air. The heated refrigerant is then returned to the compressor 216, where the process starts over again.

The frost detector 226 is configured to detect frost on the outdoor heat exchanging coil 214. The perforated plate 218 is disposed below the outdoor heat exchanging coil 214 so as to support the outdoor coil above the sub-base drip pan 220. The sub-base drip pan 220 is disposed below the perforated plate 218 so as to catch any condensate from the outdoor heat exchanging coil 214.

The air conditioning unit 200 can transfer heat from the indoor space 104 to the outdoor space 106, and vice versa, using refrigerant, in order to either cool or heat the indoor space 104. In heating mode, the air conditioning unit 200 takes heat from the outside space 106 and transfers it to the indoor space 104. In cooling mode, the air conditioning unit 200 works by taking heat from indoor space 104 and transferring it to the outdoor space 106.

In a heating mode, the valve 217 is configured to shuttle heated refrigerant from the compressor 216 to the indoor heat exchanging coil 206. The indoor heat exchanging coil 206 will draw heat from the heated refrigerant and expel the heat, thus heating the indoor space, and extract the heat from the heated refrigerant. The valve 217 then shuttles the cooled refrigerant to the outdoor heat exchanging coil 214. The outdoor heat exchanging coil 214 will draw the heat from the outdoors and use it to somewhat heat refrigerant again. This cycle continues so long as heating is needed in the indoor area.

When operating in the heating mode, frost may form on the outdoor heat exchanging coil 214. In some instances, if this frost builds up too much, the efficiency of the air conditioning unit 200 will drop. To avoid this situation, if a predetermined amount of frost is detected, e.g., by the frost detector 226, then the air conditioning unit 200 will operate in a defrost mode to melt the frost on the outdoor heat exchanging coil 214.

In certain embodiments, the air conditioning unit 200 is able to remove the water resulting from the defrosting of the outdoor heat exchanging coil 214 by pumping the water to the vaporizer 210, which turns the water to vapor. The discharge fan 212 is located in the indoor side 202 and is configured to then blow the vapor to the outdoor side 204 and eventually to the outdoors. This will be described in greater detail with reference to FIG. 3.

FIG. 3 illustrates a method 300 of operating the air conditioning unit 200. The method 300 starts (S302) and frost is detected (S304). For example, as shown in FIG. 2, the frost detector 226 detects frost on the outdoor heat exchanging coil 214 and sends a frost detection signal to the controller 224 via the communication line 230. This will be described in greater detail with reference to FIG. 4A.

FIG. 4A illustrates the controller 224 of the air conditioning unit 200 at one stage of operation. The controller 224 includes a processor 402 and a memory 404. The processor 402 is arranged to communicate with the memory 404 via a communication line 406.

In certain embodiments, the processor 402 and the memory 404 are illustrated as individual devices. However, in one or more embodiments, the processor 402 and the memory 404 may be combined as a unitary device. Any number of processors and memory may be used herein. The processor 402 may be implemented as a hardware processor such as a microprocessor, a multi-core processor, a single core processor, a field programmable gate array (FPGA), a microcontroller, an application specific integrated circuit (ASIC), a digital signal processor (DSP), or other similar processing device capable of executing any type of instructions, algorithms, or software for controlling the operation of the air conditioning unit 200 in accordance with one or more embodiments described in the present disclosure. The controller 224 may include any suitable computing devices.

The memory 404 has data and instructions, including the defrost program 408 stored therein. In one or more embodiments, the defrost program 408 includes instructions, that when executed by the processor 402, cause the controller 224 to cause the valve 217 to operate in a defrosting mode, cause the heating element 228 to generate heat, and cause the condensate pump 208 to pump condensate. The outdoor heat exchanging coil 214 operates in a defrosting mode to melt ice formed on the outdoor heat exchanging coil 214 into condensate.

In certain embodiments, the defrost program 408 includes instructions, that when executed by the processor 402, cause the controller 224 to cause a valve connecting heat exchanging coil piping (not shown) with piping (not shown) of the heating element 228 to regulate an amount of hot refrigerant to enter into the piping of the heating element 228 from the hot refrigerant in the heat exchanging coil piping. In other embodiments, the defrost program 408 includes instructions, that when executed by the processor 402, cause the controller 224 to: instruct the valve 217 to reverse the refrigerant so as to operate in a defrost mode, wherein the valve 217 shuttles the heated refrigerant as a compressed gas to the outdoor heat exchanging coil 214; to instruct the condensate pump 208 to operate; and to instruct a valve connecting heat exchanging coil piping with piping of the heating element 228 to regulate the amount of the hot refrigerant to enter into the piping of the heating element from the hot refrigerant in the heat exchanging coil piping. In addition, in some embodiments, the defrost program 408 includes instructions, that when executed by the processor 402, cause the controller 224 to instruct the condensate pump 208 to operate for a first predetermined period of time and after a second predetermined period of time after instructing the valve 217 to operate in the defrosting mode. Further, in other embodiments, the defrost program 408 includes instructions, that when executed by the processor 402, cause the controller 224 to cause the vaporizer 210 to convert the pumped condensate to vapor. In other embodiments, the defrost program 408 includes instructions, that when executed by the processor 402, cause the controller 224 to cause the discharge fan 212 to blow out the vapor created by the vaporizer 210.

The vaporizer 210 may be any known system or device the is configured to transform water to vapor, non-limiting examples of which include a vapor nozzle and a piezoelectric device.

At this stage of the method 300, the frost detector 226 sends a frost detection signal 410 to the processor 402 via the communication line 230. In certain embodiments, the frost detector 226 includes a temperature sensor that is configured to output the frost detection signal 410 as a continuous signal based on the continuously detected temperature of the outdoor heat exchanging coil 214. In these embodiments, the memory 404 may have stored therein a predetermined threshold temperature associated with a threshold amount of frost that may be formed on the outdoor heat exchanging coil 214. In some instances, the processor 402 may continuously compare the received frost detection signal 410 with the predetermined threshold temperature stored in the memory 404. In other instances, the processor 402 may periodically compare the received frost detection signal 410 with the predetermined threshold temperature stored in the memory 404. In some instances, the periodicity of the comparing may be on the order of minutes, e.g., 5 minutes. Any suitable time frame may be used herein.

In certain embodiments, the frost detector 226 includes a temperature sensor that is configured to output the frost detection signal 410 only when the detected temperature drops below a predetermined threshold temperature. In some instances, the predetermined threshold temperature is associated with a threshold amount of frost that may be formed on the outdoor heat exchanging coil 214.

FIG. 8A illustrates a first set of timing diagrams of one or more processes of the air conditioning unit 200. A timing diagram 802 corresponds to the operating of the frost detector 226. A timing diagram 804 corresponds to the operating of the heating element 228. A timing diagram 806 corresponds to the performance of a defrost mode of operation of the air conditioning unit 200. A timing diagram 808 is drawn to the operation of the condensate pump 208, the vaporizer 210, and the discharge fan 212. The timing diagrams 802, 804, 806, and 808 have a common x-axis 810, although this is shown as four separate axes to separate the respective timing diagrams.

The processor 402 receives the frost detection signal 410 from the frost detector 226 at a time t₁, as shown by function 812 of timing diagram 802, when the detected temperature drops below a predetermined threshold temperature. Returning to FIG. 3, after frost is detected (S304), heating is initiated (S306). For example, as shown in FIG. 2, the controller 224 instructs the heating element 228 to start heating. As shown in FIG. 4A, the processor 402 executes instructions in the defrost program 408 to generate a heating instruction 414, which is transmitted to the heating element 228 via the communication line 234.

The heating element 228 may be any known device or system that is able to generate heat and that may be submerged in the condensate. In one or more embodiments, the heating element 228 may be a resistive heating element surrounded by a nonconductor such as plastic or ceramic. In one or more embodiments, the heating element 228 may include a heating system in combination with a heat pipe. In some instances, the heating element 228 may include a valve in addition to bypass pipes configured to pass hot refrigerant. An example of this will now be described in greater detail with reference to FIGS. 5A-7.

FIG. 5A illustrates an oblique view of the sub-base drip pan 220 of the air conditioning unit of FIG. 2, with a siphoning pipe 502 disposed therein. The sub-base drip pan 220 has a triangular front face 506, a triangular back face 504, a side 508 and a side 510. The triangular front face 506 is connected to both the side 508 and the side 510. The triangular back face 504 is also connected to both the side 508 and the side 510, thus forming a condensate holding area 514. The side 508 and the side 510 connect to form a pointed bottom 512 of the condensate holding area 514, where the condensate will accumulate.

FIG. 5B illustrates a side view of the sub-base drip pan 220. The siphoning pipe 502 is positioned such that the end 515 is disposed at a bottom corner area 518 of the sub-base drip pan 220. The pointed bottom 512 of the sub-base drip pan 220 is angled so as to force the accumulated condensate 516 to flow toward the bottom corner area 518. This ensures that siphoning pipe 502 is able to siphon all the accumulated condensate 516.

The siphoning pipe 502 corresponds to an example of the pipe section 238 of the water transport system 222 of FIG. 2. Siphoning pipe 502 may be any material that is resistant to corrosion, non-limiting examples of which include plastic and copper piping.

In certain embodiments, the heating element 228 may be disposed within condensate holding area 514 so as to heat condensate that accumulates therein. For example, the heating element 228 may be disposed so as to contact at least one of the triangular front face 506, the triangular back face 504, the side 508, and the side 510 so as to heat the sub-base drip pan 220.

It should be noted that a sub-base drip pan in accordance with aspects of the present disclosure may have a front face and back face that is of a shape other than that of a triangle. Further, in one or more embodiments, the front face and the back face may be shaped differently from one another. In one or more embodiments, the front face and the back face of a sub-base drip pan are configured to maximize the likelihood that a majority of the accumulated condensate will be forwarded to the end of a siphoning pipe disposed within the sub-base drip pan. A sub-base drip pan in accordance with one or more embodiments having a different shape to as discussed above with reference to FIGS. 5A-B will now be described in greater detail with reference to FIGS. 6-7.

FIG. 6 illustrates a side view of a portion of the outdoor heat exchanging coil 214 and a portion of another sub-base drip pan 600 in accordance with one or more embodiments of the present disclosure. The sub-base drip pan 600 includes a slanted portion 602 and a flat accumulating portion 604. The slanted portion 602 is configured to enable the condensate that drops from the outdoor heat exchanging coil 214, through the perforated plate 218, and into the sub-base drip pan 600, will continue to fall from gravity in a direction toward the flat accumulating portion 604. In some instances, the flat accumulating portion 604 is flat so as to provide a suitable surface area for the heating element 228.

FIG. 7 illustrates the heating element 228 including a hot refrigerant bypass of one or more embodiments of the air conditioning unit of FIG. 2. As shown in FIG. 7, the flat accumulating portion 604 of the sub-base drip pan 600 extends under the compressor 216. FIG. 7 also depicts a refrigerant feed line 702, a refrigerant output line 704, a valve 706, a refrigerant bypass line 708, and a main refrigerant line 710.

In the heating mode, refrigerant enters the compressor 216 from the refrigerant feed line 702 as a low-pressure gas and is compressed to a high-pressure gas. The high-pressure gas then output from the refrigerant output line 704 through the outdoor heating coil 214, where it releases heat to the air in the outdoor space 106 and condenses into a high-pressure liquid. The high-pressure liquid then passes through an expansion valve (not shown), where it is allowed to expand and become a low-pressure liquid. The low-pressure liquid then passes through the indoor heat exchanging coil 206, where it absorbs heat from the air of the indoor space 104 and evaporates into a low-pressure gas. The low-pressure gas then returns to the compressor 216, where the cycle starts over.

In the cooling mode, refrigerant enters the compressor 216 as a low-pressure gas and is compressed to a high-pressure gas. The high-pressure gas then passes through the outdoor heat exchanging coil 214, where it releases heat to the air in the outdoor space 106 and condenses into a high-pressure liquid. The high-pressure liquid then passes through an expansion valve (not shown), where it is allowed to expand and become a low-pressure liquid. The low-pressure liquid then passes through the indoor heat exchanging coil 206, where it absorbs heat from the air in the indoor space 104 and evaporates into a low-pressure gas. The low-pressure gas then returns to the compressor 216, where the cycle starts over. In cooling mode, the air conditioning unit 200 is effectively transferring heat from the air in the indoor space 104 to the air in the outdoor space 106.

The valve 706 is configured to operate in the heating mode. For example, a portion of the refrigerant from the refrigerant output line 704 is bypassed to the refrigerant bypass line 708, and the remainder of the refrigerant from the refrigerant output line 704 is pass to the outdoor heat exchanging coil 214 via the main refrigerant line 710.

The refrigerant bypass line 708 is configured to extend down to the flat accumulating portion 604 of the sub-base drip pan 600, wherein a portion 712 of the refrigerant bypass line 708 is disposed. In some instances, the portion 712 of the refrigerant bypass line 708 is configured to have a serpentine pattern to maximize the surface area that the portion 712 covers. Any suitable pattern or shape may be used. The refrigerant bypass line 708 is configured to extend back up from the flat accumulating portion 604 of the sub-base drip pan 600 to reconnect with the main refrigerant line 710 as shown by portion 714.

In operation, the valve 706 receives the heating instruction 414 from the processor 402 via the communication line 234. In some instances, the valve 706 may be a solenoid valve. The valve 706 may be configured to divert all the heated refrigerant from the refrigerant output line 704 to the refrigerant bypass line 708. In some instances, the valve 706 may be configured to divert a predetermined portion of the heated refrigerant from the refrigerant output line 704 to the refrigerant bypass line 708, as shown by an arrow 716, and pass the remaining portion of the heated refrigerant from the refrigerant output lint 704 to the main refrigerant line 710, as shown by an arrow 718.

When the heated refrigerant passes through the portion 712 of the refrigerant bypass line 708, the flat accumulating portion 604 of the sub-base drip pan 600 is heated. This will ensure that, in the case that the sub-base drip pan 600 is so cold that condensate would freeze when it touches the sub-base drip pan 600, the sub-based drip pan 600 will be heated to prevent condensate from freezing thereon. The heated refrigerant then passes through the portion 714 of the refrigerant bypass line 708 to eventually flow out the main refrigerant line 710 to the outdoor heat exchanging coil 214.

As shown in the timing diagram 804 of FIG. 8A, the heating process starts at the time t₁, which is when the processor 402 receives the frost detection signal 410 from frost detector 226. Returning to FIG. 3, after the heating process is initiated (S306), a period of time passes (S308). As mentioned above, a reason to heat the sub-base drip pan is to prevent condensate from freezing to the sub-base drip pan in the event that the sub-base drip pan is freezing. Therefore, a predetermined amount of time may be required to ensure that the sub-base drip pan is sufficiently heated. In some instances, this predetermined amount of time may be on the order of approximately 10 seconds. More specifically, as shown in FIG. 8A, in the timing diagram 806, the defrost process starts at a time t₂, a period of time Δ₁after the heating process has started.

Returning to FIG. 3, after the predetermined time has passed (S308), a defrost process is initiated (S310). For example, as shown in FIG. 2, the controller 224 instructs the valve 217 to operate in a defrost mode, wherein the valve 217 shuttles the heated refrigerant is delivered as a compressed gas to the outdoor heat exchanging coil 214. The refrigerant will pass through the outdoor heat exchanging coil 214, thus heating the outdoor heat exchanging coil 214 and melting any frost that has built up on the outdoor heat exchanging coil 214.

As shown in FIG. 4A, processor 402 executes instructions in the defrost program 408 to generate a defrost instruction 412, which is transmitted to the valve 217 via the communication line 231. As shown in the timing diagram 806 of FIG. 8A, and as mentioned above, the defrost process starts at the time t₂. Returning to FIG. 3, after the defrost process is initiated (S310), a period of time passes (S312). As mentioned above, the condensate may be pumped away from the outdoor heat exchanging coil 214, vaporized, and then the vapor blown out to the outdoors with a fan. However, as shown in FIG. 2, operating the condensate pump 208, the vaporizer 210, and the discharge fan 212 constantly would waste energy in the event that there is no condensate to remove. To minimize energy loss, in some instances, the condensate pump 208, the vaporizer 210, and the discharge fan 212 are not turned on until there is condensate to remove. More specifically, as shown in FIG. 8A, in the timing diagram 806, the defrost process starts at the time t₂. However, the condensate pump 208, the vaporizer 210, and the discharge fan 212 are not turned on until time t₃, a period of time Δ₂after the defrost process starts. It may take some time for some frost to melt to create condensate to remove. This delay time period, Δ₂, accounts for this.

Returning to FIG. 3, after the period of time passes (S312), an extraction process is initiated (S314). For example, as shown in FIG. 2, the controller 224 instructs the condensate pump 208 to pump the condensate from the sub-base drip pan 220 to the vaporizer 210 and instructs the discharge fan 212 to blow the resulting vapor to the outdoors.

As shown in FIG. 4A, the processor 402 executes instructions in the defrost program 408 to transmit a discharge fan instruction 420 to the discharge fan 212 via the communication channel 236, transmit a condensate pump instruction 416 to the condensate pump 208 via the communication channel 238, and to transmit a vaporizer instruction 418 to the vaporizer 210 via the communication channel 240. Upon receiving the discharge fan instruction 420, the discharge fan 212 turns on. Upon receiving the condensate pump instruction 416, the condensate pump 208 turns on. Upon receiving the vaporizer instruction 418, the vaporizer 210 turns on.

Returning to FIG. 2, when the outdoor coil 214 starts defrosting, condensate falls, due to gravity, to and passes through the perforated plate 218, as shown by the arrow 242. The sub-base drip pan 220 catches the condensate that falls through the perforated plate 218. The condensate is then heated by heating element 228 with the sub-base drip pan 220. The heated condensate is then pumped by the condensate pump 208, as shown by the arrow 244, and output, as shown by output stream 246.

At this point, the vaporizer 210 converts the heated pumped condensate to vapor. The discharge fan 212 then blows the vapor out through the outdoor side, as shown by the arrow 248, wherein the vapor exits to the outside of the air conditioning unit 200. Because the condensate is ejected from the air conditioning unit 200 as a vapor, it will not drip onto passersby or form into icicles under the air conditioning unit 200. By using the heating element 228 to heat the condensate, the condensate is prevented from refreezing while in the outdoor side 204.

In the embodiment of FIG. 2, the discharge fan 212, the condensate pump 208, and the vaporizer 210 are disposed on the indoor side 202 of the air conditioning unit 200. It should be noted that at least one of these elements may be positioned in the outdoor side 204 of the air conditioning unit. However, positioning these elements on the indoor side 202 aids in maintenance of the discharge fan 212, the condensate pump 208, and the vaporizer 210. In particular, if disposed in the outdoor side 204, if any of the discharge fan 212, the condensate pump 208, or the vaporizer 210 need maintenance, then the entire air conditioning unit 200 may need to be removed to access them.

In certain embodiments, the discharge fan 212 and the vaporizer 210 may be disposed on the outdoor side 204. This will be described in greater detail with reference to FIGS. 9-11.

FIG. 9 illustrates a side view of an embodiment of the discharge fan 212, the outdoor heat exchanging coil 214, and the vaporizer 210 of the air conditioning unit 200. In this example, the outdoor heat exchanging coil 214 is configured to be disposed between the discharge fan 212 and the vaporizer 210. When the discharge fan 212 blows air through the outdoor heat exchanging coil 214, the vaporizer 210 emits the vapor into the air flow coming out of the outdoor heat exchanging coil 214. This will reduce the additional buildup of water on the outdoor heat exchanging coil 214 and thus reduce frost build up in future heating mode operations of the air conditioning unit 200.

FIG. 10 illustrates a side view of an embodiment of the discharge fan 212, the outdoor heat exchanging coil 214, and the vaporizer 210 of the air conditioning unit 200. In this example, the vaporizer 210 is configured to be disposed between the discharge fan 212 and the outdoor heat exchanging coil 214. When the discharge fan 212 blows air through the outdoor heat exchanging coil 214, the vaporizer 210 emits the vapor into the air flow going into the outdoor heat exchanging coil 214. This will increase the additional buildup of water on the outdoor heat exchanging coil 214, as compared to the example discussed above with reference to FIG. 9. However, the configuration in FIG. 10 saves space as the vaporizer 210 does not extend out past the outdoor heat exchanging coil 214.

It should be noted the placement of the vaporizer 210 may additionally be disposed to optimize removal of vapor. This will be described in greater detail with reference to FIG. 11.

FIG. 11 illustrates a front view of an embodiment of the discharge fan 214 and vaporizers of the air conditioning unit 200. Air flow through the outdoor heat exchanging coil is not uniform. On the contrary, a medium and high exit air flow zone 1102 is disposed on an outer periphery, whereas a low air flow and recirculation zone 1104 is centrally disposed. Therefore, in order to optimize removal of vapor generated by the vaporizer 210, the vaporizer can be disposed so as to emit the vapor in the medium and high exit air flow zone 1102. As shown in the figure, a plurality of vaporizers, an example of which is labeled as vaporizer 210, are distributed so as to emit vapor 1106 into the medium and high exit air flow zone 1102.

Returning to FIG. 3, after the extraction process is initiated (S314), the defrost process is terminated (S316). For example, as shown in FIG. 2, the controller 224 instructs the valve 217 to return to the heating mode via the communication line 231. This will be described in greater detail with reference to FIG. 4B.

FIG. 4B illustrates the controller of the air conditioning unit of FIG. 2 at a subsequent state of operation. As shown in the figure, the processor 402 executes instructions in the defrost program 408 and transmits a cooling instruction 422 to the valve via the communication line 231. In certain embodiments, the defrost process is performed for a predetermined period of time. In some instances, the predetermined period of time includes 3 minutes.

In some instances, the frost detector 226 may send a detection signal 424 to the processor 402 via the communication line 230. The detection signal 424 indicates that the detected temperature of the outdoor heat exchanging coil 214 has risen above a threshold temperature, which indicates that no more frost is on the outdoor heat exchanging coil 214. In these embodiments, the processor 402 executes instructions in the defrost program 408 to transmit the cooling instruction 422 based on the receipt of the detection signal 424 from the frost detector 226. As shown in FIG. 8A, in the timing diagram 806, it can be seen that the defrost process is performed at the function 816 between times t₂and t₄.

Returning to FIG. 3, after the defrost process is terminated (S316), another period of time passes (S318). For example, as shown in FIG. 4B, the processor 402 will execute instructions in the defrost program 408 to cause the processor 402 to wait a predetermined period of time after the defrost process is terminated before terminating the extraction process. Returning to FIG. 3, after the period of time passes (S318), the extraction process is terminated (S320). For example, as shown in FIG. 2, the controller 224 may instruct the condensate pump 208 to stop pumping via the communication line 238, instruct the vaporizer 210 to stop vaporizing via the communication line 240, and instruct the discharge fan 212 to stop blowing via the communication line 236.

As shown in FIG. 4B, the processor 402 is configured to transmit a stop pumping signal 426 to the condensate pump 208 via the communication line 238 to cause the condensate pump 208 to stop pumping, transmit a stop vaporizing signal 428 to the vaporizer 210 via the communication line 240 to cause the vaporizer 210 to stop vaporizing, and transmit a stop blowing signal 430 to the discharge fan 212 via the communication line 236 to cause the discharge fan 210 to stop blowing.

As shown in FIG. 8A, in the timing diagram 808, the function 818 shows the condensate pump 208, the vaporizer 210 and the discharge fan 212 operating from a time t₃to a time t₅. In some instances, the period of time from the time t₃to the time t₅is on the order of 5 minutes. It should be noted that the condensate pump 208, the vaporizer 210, and the discharge fan 212 stop operating at a time period Δ₃after the defrost process terminates and after the heating element 228 stops heating. This ensures that any condensate that falls at the end of the defrost process will make its way through the water transport system 222, be vaporized by the vaporizer 210, and be blown out by the discharge fan 212.

In this example, the condensate pump 208, the vaporizer 210, and the discharge fan 212 are all indicated as stopping at the same time, t₅. However, in one or more embodiments, the condensate pump 208, the vaporizer 210, and the discharge fan 212 may stop at different times. In particular, in some instances, the condensate pump 208 may stop first, followed by the vaporizer 210, and finally followed by the discharge fan 212.

Returning to FIG. 3, after the extraction process is terminated (S320), the heating process is terminated (S322). For example, as shown in FIG. 2, the controller 224 is configured to instruct the heating element 228 to stop heating via the communication line 234. This will be described in greater detail with reference to FIG. 4B. As shown in the FIG. 4B, the processor 402 executes instructions in the defrost program 408 and transmits a stop heating instruction 432 to the heating element 228 via the communication line 234.

As shown in FIG. 8A, in the timing diagram 804, it can be seen that the heating process is performed at function 814 between times t₁and t₅.

Returning to FIG. 3, after the heating process is terminated (S322), method 300 ends (S324). Accordingly, as a result of method 300, when the outdoor heating exchange coil is defrosted the condensate is collected, heated by the heating element 228, pumped to the indoor side 202 of the air conditioning unit, and vaporized by the vaporizer 210. The vapor is then blown outside of the air conditioning unit by the discharge fan 212. Therefore, the condensate resulting from the defrost process does not drip out from the bottom of the air conditioning unit 200 and does not form icicles on the outside bottom of the air conditioning unit 200.

In the embodiments discussed above with reference to FIGS. 3 and 8A, the heating process is started before the defrosting process. However, in one or more embodiments, the heating process may start after the defrosting process. This will be described in greater detail with reference to FIG. 8B.

FIG. 8B illustrates a second set of timing diagrams of one or more processes of the air conditioning unit 200. A timing diagram 820 corresponds to the operating of the frost detector 226. A timing diagram 822 corresponds to the operating of the heating element 228. A timing diagram 824 corresponds to the performance of a defrost mode of operation of the air conditioning unit 200. A timing diagram 826 is drawn to the operation of the condensate pump 208, the vaporizer 210, and the discharge fan 212. The timing diagrams 820, 822, 824, and 826 have a common x-axis 828, although this is shown as four separate axes to separate the respective timing diagrams.

In this example, the processor 402 receives the frost detection signal 410 from the frost detector 226 at a time t₆, as shown by function 830 of timing diagram 820, when the detected temperature drops below a predetermined threshold temperature. In contrast with the embodiment discussed above with reference to FIGS. 3 and 8A, in this example, the defrost process starts when the processor 402 receives the frost detection signal 410 at a time t₆, as shown by the function 834. Then, after a predetermined time delay, Δ₄, the heating process starts at a time t₇. The heating process may be delayed in these embodiments to save power. The defrost process is performed from the time t₆to a time t₉, as shown by a function 834. The heating process is performed from the time t₇to a time t₁₀as shown by a function 832. The heating process continues for the time period Δ₃after termination of the defrost process. The condensate pump 208, the vaporizer 210, and the discharge fan 212 start operating the time period Δ₂after the heating process starts at time t₈. The function 836 shows the condensate pump 208, the vaporizer 210 and the discharge fan 212 operating from a time t₈to the time t₁₀.

FIG. 8C illustrates a third set of timing diagrams of one or more processes of the air conditioning unit 200. A timing diagram 838 corresponds to the operating of the frost detector 226. A timing diagram 840 corresponds to the operating of the heating element 228. A timing diagram 842 corresponds to the performance of a defrost mode of operation of the air conditioning unit 200. A timing diagram 844 is drawn to the operation of the condensate pump 208, the vaporizer 210, and the discharge fan 212. The timing diagrams 838, 840, 842, and 844 have a common x-axis 846, although this is shown as four separate axes to separate the respective timing diagrams.

In this example, the processor 402 receives the frost detection signal 410 from the frost detector 226 at a time t₁₁, as shown by function 848 of timing diagram 838, when the detected temperature drops below a predetermined threshold temperature. In contrast with the embodiment discussed above with reference to FIGS. 3 and 8B, in this example, the heating process starts at the same time that the condensate pump 208, the vaporizer 210 and the discharge fan 212 start operating, which is at a time t₁₃, as shown by the function 854.

In this example, the defrost process starts at a time t₁₂, a predetermined delay period Δ₅after the processor 402 receives the frost detection signal 410 from the frost detector 226. Then, after a predetermined time delay, Δ₆, the heating process, the condensate pump 208, the vaporizer 210, and the discharge fan 212 start at a time t₁₃. The heating process may be delayed in these embodiments to save more power because it does not start until the condensate pump 208, the vaporizer 210, and the discharge fan 212 start.

The defrost process is performed from the time t₁₂to a time t₁4, as shown by a function 852. The heating process is performed from the time t₁₃to a time tis, as shown by a function 850. The heating process continues for the time period Δ₃after termination of the defrost process. The condensate pump 208, the vaporizer 210, and the discharge fan 212 start operating the time period Δ₆after the defrost process starts at time t₁₂. The function 854 shows the condensate pump 208, the vaporizer 210, and the discharge fan 212 operating from a time t₁₃to the time t₁₅.

FIGS. 12A-1B illustrate a portion of another air conditioning unit 1200 (FIG. 12A shows a top-down view of the air conditioning unit 1200 and FIG. 12B shows a side view of the air conditioning unit 1200). Particularly, FIGS. 12A-12B show air conditioning unit configurations used to prevent frost buildup around an outdoor fan 1202 of the air conditioning unit 1200.

Air conditioning unit 1200 may include similar elements as air conditioning unit 200 or any other air conditioning unit described herein or otherwise. For example, air conditioning unit 1200 may include outdoor coil 1204 (which may be the same as outdoor coil 214), compressor 1206 (which may be the same as compressor 216), expansion valve 1207, drain pan 1208, etc. Air conditioning unit 1200 also includes sump loop 1210, which is provided proximate to the outdoor fan 1202. For example, the sump loop 1210 may partially or fully surround the outdoor fan 1202 or may be provided proximate to the outdoor fan 1202 in any other suitable arrangement. To prevent frost accumulation (or remove frost that has already accumulated) on the outdoor fan 1202, hot refrigerant from the compressor 1206 may flow through the sump loop 1210 and around the outdoor fan 1202. The hot refrigerant heats the sump loop 1210, which prevents the frost accumulation (or removed frost that has accumulated).

It should be noted that in the embodiments discussed above, a condensate pump pumps condensate to a vaporizer, which vaporizes the condensate, which is then blown out from the air conditioning unit by a discharge fan. However, in one or more other embodiments, the condensate may be pumped to an external area of the air conditioning unit. For example, in some cases, the condensate may be pumped to a sink or drain that is external to the air conditioning unit.

In typical air conditioning units, when a defrost procedure is performed to remove frost from the outdoor heat exchanging coils, the resulting condensate drips from the outdoor portion of the air conditioning unit. Further, in some cases, this condensate may form icicles on the outside of the air conditioning unit. These icicles may be problematic for passersby or property if they detach from the air conditioning unit and fall.

In accordance with one or more embodiments of the present disclosure, when a defrost procedure is performed to remove frost from the outdoor heat exchanging coils, the resulting condensate collected in a drip pan is heated in the drip pan and pumped to a vaporizer. The vapor is then ejected from the air conditioning unit. As such, there is no dripping of the condensate from the air conditioning unit and there are no icicles forming on the air conditioning unit from the condensate.

It should be apparent that the foregoing relates only to certain embodiments of the present disclosure and that numerous changes and modifications may be made herein by one of ordinary skill in the art without departing from the general spirit and scope of the disclosure.

Although specific embodiments of the disclosure have been described, numerous other modifications and alternative embodiments are within the scope of the disclosure. For example, any of the functionality described with respect to a particular device or component may be performed by another device or component. Further, while specific device characteristics have been described, embodiments of the disclosure may relate to numerous other device characteristics. Further, although embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as illustrative forms of implementing the embodiments. Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments could include, while other embodiments may not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments.

Systems and Methods for Heating and Removing Condensation from Air Conditioning Units

Information

Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

International Classifications

Abstract

Description

Claims

CROSS-REFERENCE TO RELATED APPLICATIONS

Provisional Applications (1)