US20060005548A1

US20060005548A1 - Countertop thermoelectric assembly

Info

Publication number: US20060005548A1
Application number: US10/887,184
Authority: US
Inventors: Keith Ruckstuhl
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-07-08
Filing date: 2004-07-08
Publication date: 2006-01-12

Abstract

A countertop thermoelectric assembly includes a countertop forming a food preparation surface at an upper side thereof, at least one Peltier effect device located below the countertop, a thermal transfer plate located between the countertop and the thermoelectric device, a heat sink in thermal communication with the thermoelectric unit, and a controller to selectively operate the thermoelectric unit to cool and/or warm the food preparation surface formed by the countertop. A first temperature sensor located to provide signals representative of a temperature of the countertop. A second temperature sensor located to provide signals representative of a temperature of the heat sink. A condensation shield is located below the heat sink. A moisture sensor is located to provide signals representative of moisture at the condensation shield. At least one fan is located below the countertop to direct air over the heat sink and/or the condensation shield.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable

REFERENCE TO MICROFICHE APPENDIX

Not Applicable

FIELD OF THE INVENTION

The present invention generally relates to a device for cooling and/or heating a food preparation surface such as a kitchen countertop and, more particularly, to an assembly having a thermoelectric or “Peltier effect” unit for cooling and/or heating a food preparation surface such as a kitchen countertop.

BACKGROUND OF THE INVENTION

It is sometimes desirable to have a cool working or preparation surface when preparing certain foodstuffs such as, for example, confectioneries like fudge. Such food preparation surfaces are often made from natural stone such as, for example, granite. The natural stone has thermal properties such that it tends to remain relatively cool in most kitchen environments, particularly when the stone has a relatively large thickness. Granite also has other properties such as hardness, scratch resistance, ease of cleaning which make it a desirable material for food preparation surfaces. In commercial kitchens, granite food preparation surfaces and other thermally conductive food preparation surfaces such as, for example, stainless steel are sometimes provided with refrigeration systems to insure a desirable temperature of the preparation surface. An additional benefit of using a granite or other cold preparation surface is that it somewhat cools the ambient temperature of an otherwise warm kitchen environment.
Granite, stainless steel, and the like are also popular materials for countertops in residential kitchens because of their natural beauty as well as the above-identified properties suitable for food preparation surfaces. However, because of the relatively thin material thickness of residential countertops, the food preparation surface is typically not as naturally cool as desired for preparing some foodstuffs such as, for example, confectionaries like fudge. Additionally, the refrigeration systems used in commercial kitchens are cost and space prohibitive for most residential kitchens.
It is also sometimes desirable to have a warm working or preparation surface when preparing certain foodstuffs such as, for example, baked goods like bread. In commercial kitchens, food preparation surfaces are sometimes provided with heater systems to insure a desirable temperature at the preparation surface. Residential cooking stoves or ranges sometimes have smooth top cooking surfaces but these cooking surfaces provide temperatures which are too high to operate as a food preparation surface for some operations where cooking is not desired such as, for example, a warm surface for rising bread. Additionally, the heater systems used in commercial kitchens are cost and space prohibitive for most residential kitchens.
Therefore, most “home chefs” must make do with less than ideal conditions and commercial chefs must purchase multiple systems which are relatively expensive and space consuming. Accordingly, there is a need in the art for an improved device for cooling and/or heating food preparation surfaces such as a countertop or the like.

SUMMARY OF THE INVENTION

The present invention provides a countertop thermoelectric assembly which overcomes at least some of the above-noted problems of the related art. According to the present invention, a thermoelectric assembly comprises, in combination, a panel forming a preparation surface at an upper side thereof, at least one thermoelectric unit located below the panel and in thermal communication with the panel, a heat sink in thermal communication with the thermoelectric unit, and a controller in electrical communication with the thermoelectric unit to selectively operate the thermoelectric unit to change a temperature of the preparation surface.
According to another aspect of the present invention, a countertop thermoelectric assembly comprises, in combination, a portion of a countertop forming a food preparation surface at an upper side thereof and at least one thermoelectric unit located below the countertop and in thermal communication with the countertop. The thermoelectric unit is a Peltier effect device. A thermal transfer plate is located between the countertop and the thermoelectric device. A heat sink is in thermal communication with the thermoelectric unit. A controller is in electrical communication with the thermoelectric unit to selectively operate the thermoelectric unit to change a temperature of the food preparation surface formed by the countertop. A first temperature sensor is in electrical communication with the controller and located to provide signals representative of a temperature of the countertop. A second temperature sensor is in electrical communication with the controller and located to provide signals representative of a temperature of the heat sink.
According to yet another aspect of the present invention, a countertop thermoelectric assembly comprises, in combination, a portion of a countertop forming a food preparation surface at an upper side thereof and at least one thermoelectric unit located below the countertop and in thermal communication with the countertop. The thermoelectric unit is a Peltier effect device. A thermal transfer plate is located between the countertop and the thermoelectric device. A heat sink is in thermal communication with the thermoelectric unit. A controller is in electrical communication with the thermoelectric unit to operate the thermoelectric unit to selectively cool and warm the food preparation surface formed by the countertop. A first temperature sensor is in electrical communication with the controller and located to provide signals representative of a temperature of the countertop. A second temperature sensor is in electrical communication with the controller and located to provide signals representative of a temperature of the heat sink. A condensation shield is located below the heat sink and a moisture sensor in electrical communication with the controller and located to provide signals representative of moisture at the condensation shield.
From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology and art of thermal control units for food preparation surfaces. Particularly significant in this regard is the potential the invention affords for providing a high quality, reliable, low cost assembly. Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.

BRIEF DESCRIPTION OF THE DRAWINGS

These and further features of the present invention will be apparent with reference to the following description and drawing, wherein:
FIG. 1 is a top plan view of a countertop thermoelectric assembly according to the present invention;
FIG. 2 is a front elevational view of the countertop thermoelectric assembly of FIG. 1;
FIG. 3 is a side elevational view of the thermoelectric assembly of FIGS. 1 and 2;
FIG. 4 is a diagrammatic view of the thermoelectric assembly of FIGS. 1 to 3;
FIG. 5 is a diagrammatic view of an alternative thermoelectric assembly according to the present invention; and
FIG. 6 is a diagrammatic view of the thermoelectric assembly of FIG. 5 showing inlet and outlet vents.
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of a countertop thermoelectric assembly as disclosed herein, including, for example, specific components, shapes and dimensions will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration. All references to direction and position, unless otherwise indicated, refer to the orientation of the countertop thermoelectric assembly illustrated in the drawings. In general, up or upward refers to an upward direction within the plane of the paper in FIGS. 2 and 3 and down or downward refers to a downward direction within the plane of the paper in FIGS. 2 and 3. Also in general, fore or forward refers to a direction toward the front of the countertop and/or kitchen cabinet, that is, a rightward direction within the plane of the paper in FIG. 3 and aft or rearward refers to a direction toward the rear of the countertop and/or kitchen cabinet, that is, a leftward direction within the plane of the paper in FIG. 3.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS

It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the improved countertop thermoelectric assemblies disclosed herein. The following detailed discussion of various alternative and preferred embodiments will illustrate the general principles of the invention with reference to countertop thermoelectric assemblies for use in cooling and/or heating residential or home food preparation surfaces such as kitchen countertops. Other embodiments suitable for other applications such as, for example, commercial food preparation surfaces or the like will be apparent to those skilled in the art given the benefit of this disclosure.
Referring now to the drawings, FIGS. 1 to 4 show a countertop thermoelectric assembly 10 installed on a residential kitchen countertop according to the present invention. The thermoelectric assembly 10 includes a panel such as a countertop 12 forming a food preparation surface 14, at least one thermoelectric device or unit 16 located below the countertop 12 and in thermal communication with the countertop 12, a thermal transfer plate or cold sink 18 located between the countertop 12 and the thermoelectric unit 16, a thermal transfer body or heat sink 20 in thermal communication with the thermoelectric unit 16, and a controller or control unit 22 in electrical communication with the thermoelectric unit 16 to selectively operate the thermoelectric unit 16 to cool and/or warm the preparation surface 14.
The illustrated thermoelectric assembly 10 is installed on a standard kitchen cabinet 24 supporting the countertop or panel 12. The panel 12 covers the open top of the cabinet 24 and has a planar top surface which forms the food preparation surface 14 and a planar bottom surface 26 facing the interior space of the cabinet 24. The panel 12 preferably comprises a solid surface counter material such as, for example, natural stone like granite or marble, stainless steel, poured concrete or man-made solid surface counter materials but any other suitable material can alternatively be utilized. The illustrated countertop 12 includes an insert panel 28 held in an opening in the panel 12 by a support bracket 30. The illustrated support bracket 30 is generally Z-shaped in cross-section but another other suitable bracket or support means can alternatively be utilized. The illustrated insert panel 28 has a planar top surface 2 which forms the food preparation surface and a planar bottom surface facing the interior space of the cabinet 24. The insert panel 28 is positioned so that the upper surfaces of the panel 12 and the insert panel 28 form the substantially continuous food preparation surface 14. The insert panel 28 preferably comprises solid surface counter material such as, for example, a natural stone material like granite or marble, or man-made solid surface counter materials but any other material suitable for cooling and/or warming by the thermoelectric unit 16 can alternatively be utilized. It noted that the insert panel 28 can alternatively be eliminated so that the thermoelectric unit 16 directly cools and/or warms the panel 12 without the opening or the insert panel 28. It is further noted that the insert panel 28 is preferably eliminated when the panel 12 comprises a suitable material for cooling and/or warming by the thermoelectric unit 16 such as, for example, a natural stone material (best shown in FIG. 4) but the insert panel 28 is preferably utilized when the panel 12 comprises a material not suitable for cooling and/or warming by the thermoelectric unit 16 such as, for example, a laminate material (best shown in FIGS. 1 to 3).
The illustrated cabinet 24 has a drawer 32 located near the top of the cabinet 24 which opens in a forward. Mounted in this manner, the open top of the drawer 32 faces the bottom surface 26 of the countertop 12 when the drawer 32 is closed. Below the drawer 32 is a hinged door 34 which selectively provides access to a storage space 36 located below the drawer 32. It is noted that the cabinet 24 can alternatively have any suitable, size, shape, and form such as, for example, the drawer 32 and/or hinged door 34 could be altered and/or eliminated.
As best shown in FIG. 4, the illustrated thermoelectric unit 16 is located below the panel 12 and in thermal communication with the panel 12 so that operation of the thermoelectric unit 16 cools and/or heats the panel 12 so that the food preparation surface 14 is at a desired temperature. The thermoelectric unit 16 is preferably a Peltier effect device, that is a device sometimes referred to as a “semiconductor refrigerator” that works according to the Peltier effect and either cools or warms an object depending on the direction of current flow therethrough. Such a thermoelectric device 16 typically includes an array of semiconductor couples electrically connected in series and thermally connected in parallel. The semiconductor couples are typically sandwiched between metalized ceramic substrates. When DC electric current is applied in series to the thermoelectric device 16, it acts as a heat pump with heat being absorbed on the cold side, thereby cooling it, while heat is dissipated at the other side. Reversing the current causes the direction of heat flow to be reversed. Attaching a heat sink 20 and a cold sink 18 to the respective hot and cold sides enhances the efficiency of the thermoelectric device 16.
It is noted that more than one thermal electric unit 16 can be stacked together to produce a sharper thermal gradient and decrease the cooling or warming time for the area of the food preparation surface 14 to be cooled or warmed. It is also noted that more than one thermal electric unit 16 or more than one stack of thermoelectric units 16 can be utilized to increase the overall area of the food preparation surface 14 to be cooled or warmed or, if adequately spaced, to provide more than one distinctly different area of the food preparation surface 14 to be independently cooled or warmed. The thermoelectric assembly 10 of FIGS. 1 to 3, utilizes four of the thermoelectric units 16 to create a relatively large area of the food preparation surface 14 which is cooled and warmed.
As best shown in FIG. 4, the thermal transfer plate 18 is a substantially planar member located between the thermoelectric unit 16 and the bottom surface 26 of the panel 12. The thermal transfer plate 18 preferably is sized substantially equal to area of the food preparation surface 14 which is desired to be cooled and/or warmed. The thermal transfer plate 18 provides a larger footprint than the thermoelectric unit 16 to aid in the transfer of heat over a larger area. The thermal transfer plate 18 preferably comprises a material having a relatively high coefficient of thermal conductivity such as, for example, copper, aluminum, and/or the like. The thermal transfer plate 18 is preferably provided with a suitable thermal transfer medium 38 such as, for example, thermal transfer grease or tape at its interfaces with the panel 12 and the thermoelectric unit 16 to improve heat transfer therebetween.
The heat sink 20 is located below the thermoelectric unit 16 and in thermal communication therewith. The heat sink 20 can be unitary with the thermoelectric unit 16 or suitably connected thereto. The heat sink 20 is preferably provided with a suitable thermal transfer medium 40 such as, for example, thermal transfer grease or tape at its interface with the thermoelectric unit 16 to improve heat transfer therebetween. The heat sink 20 is sized and shaped to provide a suitable surface area for the transfer of heat. The heat sink 20 is preferably provided with fins 42 to increase its exterior surface area. The heat sink 20 preferably comprises a material having a relatively high coefficient of thermal conductivity such as, for example, copper, aluminum, and/or the like.
A layer of thermally insulating material 44 is preferably provided at the lower side of the thermal transfer plate 18 to ensure that the thermal gradient does not “self cancel.” The layer 44 preferably cover substantially all of the lower surface of the thermal transfer plate 18 which is not covered by the thermoelectric unit or units 16. The layer 44 can comprise any suitable thermally insulating material.
The controller or control unit 22 is adapted to control operation of the thermoelectric assembly 10 so that the thermoelectric unit 16 selectively cools and/or warms the panel 12. The control unit 22 is in electrical communication with the thermoelectric unit 16 and a suitable power supply 46. The electric communication can be provided by hard wiring, wireless technology, or a combination. The wireless technology utilized can be, for example, X-10, Bluetooth, or other communication protocols. The illustrated control unit 22 is located above the countertop 12 but can alternatively be located at any other desired location. The control unit 22 preferably includes user input means for initiating cooling and/or warming of the panel 12 by the thermoelectric unit 16, selecting one of multiple temperature settings such as, for example high and low settings (the control unit 22 can alternatively permit the input of a desired temperature), selecting a duration of time for operation of the thermoelectric unit 16 until operation of the unit automatically shuts off such as, for example, duration of between thirty minutes and two hours (the control unit 22 can alternatively operate the thermoelectric unit 16 for a predetermined non-user adjusted period of time),and selecting between more than one temperature controlled zone when applicable. It is noted that the thermoelectric assembly 10 operates within a temperature range which warms the panel 12 to aid in food preparation but does not heat the panel 12 to a temperature which cooks food.
The illustrated thermoelectric assembly 10 also includes first and second temperature sensors 48, 50 which are in electrical communication with the control unit 22. The first temperature sensor 48 is located at the bottom surface 26 of the countertop 12 to provide a signal representative of the temperature at the countertop 12. The control unit 22 can use this signal to stop operation of the thermoelectric unit 16 or activate a fan (as described in more detail hereinafter) when the countertop temperature reaches a predetermined cutoff temperature or when a predetermined temperature gradient is present across the thermoelectric unit 16. The second temperature sensor 50 is located at the heat sink 20 to provide a signal representative of the temperature of the heat sink 20. The control unit 22 preferably uses this signal to stop operation of the thermoelectric unit 16 or activate a fan (as described in more detail hereinafter) when the heat sink 20 temperature reaches a predetermined cutoff temperature or when a predetermined temperature gradient is present across the thermoelectric unit 16. The temperature sensors 48, 50 can be any suitable type of device which provides a signal representative the temperature of a desired location.
The illustrated thermoelectric assembly 10 of FIGS. 1 to 3, includes a condensation guard 52 in the form of a tray or container for catching and holding condensation which drips from the heat sink 20. The illustrated condensation guard 52 sits in the drawer 32 of the cabinet 24 below the heat sink 20 when the drawer 32 is closed. It is noted that the condensation guard 52 can take other shapes, sizes and locations.
As best shown in FIG. 4, the various components of the thermoelectric assembly 10 are preferably sized and shaped so that the thermoelectric assembly 10 has a height small enough that the thermoelectric assembly 10 is located entirely above the top of the drawer 32. The components of the thermoelectric assembly 10 preferably extend below bottom surface 26 of the panel 12 no more than about 1.5 to about 2 inches. Sized in this manner, the drawer 32 can be opening and closed in a normal manner without damage to the thermoelectric assembly 10 and/or drawer 32 or alteration to the cabinet 24 or the drawer 32. If the thermoelectric assembly 10 extends below the top of the drawer 32, the drawer 32 is preferably provided with a notch or openings 54, so that the drawer 32 can be opened and closed without contacting the thermoelectric assembly 10.
It is noted that solid surface countertops do not allow any direct means of attachment thereto. Therefore, when a solid surface countertop is present, a mounting bracket assembly is used to secure the thermoelectric assembly 10 to the cabinet 24 and support the thermoelectric assembly 10 in the desired position in contact with the bottom surface 26 of the panel 12. It is believed that a mounting bracket similar to a cabinet drawer runner can be affixed horizontally in the cabinet 24 with a spring member and/or adjusting member which provides upward pressure to keep the assembly pressed against the bottom surface 26 of the panel 12. When an insert panel 28 is used in conjunction with a non-solid surface countertop, a mounting bracket can secure the thermoelectric assembly 10 as described above, directly to the countertop 12, or to the support bracket 30 of the insert pane 28.
FIGS. 5 and 6 show a countertop thermoelectric assembly 60 according to a second embodiment of the invention which is substantially the same as the thermoelectric assembly 10 of FIGS. 1 to 4 and common reference numbers are utilized throughout. The thermoelectric assembly 60 additionally includes at least one electric fan 62 which is located to direct air over the heat sink 20 to aid in the dissipation of heat therefrom. Additional fans 62 can be provided for this and/or other purposes such as for example, ventilation, backup in case of failure of the first fan 62, to dry the condensation guard 52. The illustrated embodiment positions a single fan 62 for directing air over both the heat sink 20 and the condensation guard 52.
The illustrated thermoelectric assembly 60 also is provided with a housing or enclosure 64 which encloses the thermoelectric unit 16 and the heat sink 20. The enclosure 64 is provided with an air inlet 66 and an air outlet 68. The illustrated air inlet 66 and air outlet 68 are connected to inlet and outlet vents 70, 72 in the front of the cabinet 24 by inlet and outlet ducts or conduits 74, 76. The ducts 74, 76 are preferably flexible tubes but can alternatively can any suitable form. Fresh air from the room enters the first vent 70 and travels through the first duct 74 to the air inlet 66, through the air inlet 66 into the enclosure 64, through the enclosure 64 over the heat sink 20 and condensation guard 52, out of the enclosure 64 through the air outlet 68, through the second duct 76 to the second vent 72 and back into the room. Circulation continues as long as the fan 62 operates. It is noted that alternatively, the inlet vent 70 and inlet duct 74 can be eliminated so that are is drawn from the interior space 36 of the cabinet 24 when there is adequate air mass available within the cabinet. The fan 62 can operate whenever the thermoelectric unit 16 is operating and/or can be activated when certain predetermined conditions are present. The illustrated condensation guard 52 is in the form of a tray at the bottom of the enclosure 64. The illustrated condensation guard 52 forms the lower portion of the enclosure 64 and provides protection against condensation dripping into the drawer 32 from the heat sink 20.
The illustrated thermoelectric assembly 60 also is provided with a water or moisture sensor 78 in electrical communication with the with the control unit 22. The moisture sensor 78 is located to provide a signal representative of the moisture at the condensation guard 52 and/or within the enclosure 64. The control unit 22 preferably uses this signal to continue operation of the fan 62 or activate the fan 62 until all water in the condensation guard 52 and/or enclosure 64 is evaporated. The moisture sensor 78 can be any suitable type of device which provides a signal representing the presence of moisture or water at a desired location.
From the above description, it should be appreciated that the present invention provides a countertop thermoelectric assembly 10 and method for warming and cooling a countertop which is relatively simple and inexpensive to produce and operate.
From the foregoing disclosure and detailed description of certain preferred embodiments, it will be apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the present invention. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled.

Claims

1. A thermoelectric assembly comprising, in combination:

a built-in kitchen cabinet having a hinged door to selectively provide access to an interior storage space of the kitchen cabinet;

wherein the kitchen cabinet has an open top;

a kitchen countertop supported on a top of the kitchen cabinet and closing the open top of the kitchen cabinet;

wherein at least a portion of the countertop forms a food preparation surface at an upper side thereof;

at least one thermoelectric unit located below the countertop within the kitchen cabinet and in thermal communication with the countertop;

a heat sink in thermal communication with the thermoelectric unit; and

a controller in electrical communication with the thermoelectric unit to selectively operate the thermoelectric unit to change a temperature of the food preparation surface without substantially changing a temperature of the interior storage space.

2. The thermoelectric assembly according to claim 1, wherein the thermoelectric unit is a Peltier effect device.

3. The thermoelectric assembly according to claim 1, wherein the countertop comprises at least one material selected from the group of natural stone, stainless steel and concrete.

4. The thermoelectric assembly according to claim 1, wherein the kitchen cabinet includes a storage drawer located between the open top and the interior storage space and the thermoelectric device is located above the drawer and does not substantially change an interior temperature of the storage drawer.

5. The thermoelectric assembly according to claim 1, further comprising a thermal transfer plate located between the countertop and the thermoelectric device.

6. The thermoelectric assembly according to claim 5, wherein the thermal transfer plate comprises a material having a relatively high thermal conductivity.

7. The thermoelectric assembly according to claim 5, wherein the thermal transfer plate extends beyond the thermoelectric unit and at least a portion of a lower side of the thermal transfer plate is provided with insulation.

8. The thermoelectric assembly according to claim 1, further comprising a temperature sensor in electrical communication with the controller and located to provide signals representative of a temperature of the preparation surface.

9. The thermoelectric assembly according to claim 8, further comprising at least one fan located below the countertop and within the kitchen cabinet to direct air over the heat sink, and wherein the controller operates the fan after the controller stops operation of the thermoelectric until signals from the temperature sensor indicate that a thermal load of the thermoelectric unit is above or below a predetermined level.

10. The thermoelectric assembly according to claim 1, further comprising a temperature sensor in electrical communication with the controller and located to provide signals representative of a temperature of the heat sink.

11. The thermoelectric assembly according to claim 10, further comprising at least one fan located below the countertop and within the kitchen cabinet to direct air over the heat sink, and wherein the controller operates the fan after the controller stops operation of the thermoelectric until signals from the temperature sensor indicate that a thermal load of the thermoelectric unit is above or below a predetermined level.

12. The thermoelectric assembly according to claim 1, further comprising at least one fan located below the countertop and within the kitchen cabinet to direct air over the heat sink.

13. The thermoelectric assembly according to claim 12, further comprising an enclosure about the heat sink and the fan and having an air outlet.

14. The thermoelectric assembly according to claim 13, wherein the air inlet and the air outlet are each in communication with an external environment about the kitchen cabinet through vents in a front wall of the kitchen cabinet.

15. The thermoelectric assembly according to claim 1, further comprising a condensation shield located below the heat sink.

16. A thermoelectric assembly comprising, in combination:

a panel forming a preparation surface at an upper side thereof;

at least one thermoelectric unit located below the panel and in thermal communication with the panel;

a heat sink in thermal communication with the thermoelectric unit;

a controller in electrical communication with the thermoelectric unit to selectively operate the thermoelectric unit to change a temperature of the preparation surface;

a condensation shield located below the heat sink; and

a moisture sensor in electrical communication with the controller and located to provide signals representative of moisture at the condensation shield.

17. The thermoelectric assembly according to claim 16, further comprising at least one fan located below the panel to direct air over the condensation shield, and wherein the controller operates the fan after the controller has stopped operation of the thermoelectric unit when signals from the moisture sensor indicate moisture is not present at the condensation shield.

18. The thermoelectric assembly according to claim 16, further comprising at least one fan located below the panel to direct air over the condensation shield, and wherein the controller operates the fan when signals from the moisture sensor indicate moisture is present at the condensation shield.

19. The thermoelectric assembly according to claim 1, wherein the controller is in electrical communication with the thermoelectric unit to operate the thermoelectric unit to selectively cool and warm the preparation surface.

20. A countertop thermoelectric assembly comprising, in combination:

wherein the kitchen cabinet has an open top;

a kitchen countertop supporting the kitchen cabinet and closing the open top of the kitchen cabinet;

wherein at least a portion of a the countertop forms a food preparation surface at an upper side thereof;

at least one thermoelectric unit located below the countertop within the kitchen cabinet and in thermal communication with the countertop through the open top of the kitchen cabinet;

wherein the thermoelectric unit is a Peltier effect device;

a thermal transfer plate located between the countertop and the thermoelectric device;

a heat sink in thermal communication with the thermoelectric unit;

a controller in electrical communication with the thermoelectric unit to selectively operate the thermoelectric unit to change a temperature of the food preparation surface formed by the countertop without substantially changing a temperature of the interior storage space;

a first temperature sensor in electrical communication with the controller and located to provide signals representative of a temperature of the countertop; and

a second temperature sensor in electrical communication with the controller and located to provide signals representative of a temperature of the heat sink.

21. The countertop thermoelectric assembly according to claim 20, further comprising at least one fan located below the countertop to direct air over the heat sink.

22. The countertop thermoelectric assembly according to claim 21, further comprising an enclosure about the heat sink and the fan and having an air outlet.

23. The thermoelectric assembly according to claim 20, wherein the controller is in electrical communication with the thermoelectric unit to operate the thermoelectric unit to selectively cool and warm the preparation surface.

24. A countertop thermoelectric assembly comprising, in combination:

a portion of a countertop forming a food preparation surface at an upper side thereof;

at least one thermoelectric unit located below the countertop and in thermal communication with the countertop;

wherein the thermoelectric unit is a Peltier effect device;

a heat sink in thermal communication with the thermoelectric unit;

a controller in electrical communication with the thermoelectric unit to operate the thermoelectric unit to selectively cool and warm the food preparation surface formed by the countertop;

a first temperature sensor in electrical communication with the controller and located to provide signals representative of a temperature of the countertop;

a second temperature sensor in electrical communication with the controller and located to provide signals representative of a temperature of the heat sink;

a condensation shield located below the heat sink; and

25. The countertop thermoelectric assembly according to claim 24, further comprising at least one fan located below the countertop to direct air over the heat sink.

26. The countertop thermoelectric assembly according to claim 25, further comprising an enclosure about the heat sink and the fan and having an air outlet.

27. The countertop thermoelectric assembly according to claim 24, further comprising at least one fan located below the countertop to direct air over the condensation shield.

28. The countertop thermoelectric assembly according to claim 1, wherein the countertop includes an insert panel having a planar top surface forming the food preparation surface and flush with a planar top surface of a portion of the countertop surrounding the insert panel.

29. The thermoelectric assembly according to claim 4, wherein the thermoelectric unit has a low profile so that the thermoelectric unit is located entirely above the effective storage space of the drawer.

30. The countertop thermoelectric assembly according to claim 20, wherein the kitchen cabinet includes a storage drawer located between the open top and the interior storage space and the thermoelectric device is located above the drawer and does not substantially change an interior temperature of the storage drawer.

31. The countertop thermoelectric assembly according to claim 30, wherein the thermoelectric unit has a low profile so that the thermoelectric unit is located entirely above the effective storage space of the drawer.

32. The countertop thermoelectric assembly according to claim 20, wherein the countertop includes an insert panel having a planar top surface forming the food preparation surface and flush with a planar top surface of a portion of the countertop surrounding the insert panel.