F A Q

Frequently Asked Questions:

General:

  •  How does TECA rate air conditioner performance?
    TECA defines its rating point as the amount of heat removed when the enclosure temperature equals the ambient temperature, or at 0 delta T. This is the preferred industry method. Because of the differing performances at various ambients, we often state this as a range. Since there is no industry standards other manufacturers may choose different definitions; such as rating performance at 20° above ambient. It is important for a user to understand these subtleties to ensure they are “comparing apples to apples.”
  • What process does TECA use to arrive at their published performance curves?
    Our curves are a result of testing. The curves are a linear line fit to the results of the testing. The values used are the total load being removed by the air conditioner VS the average enclosure temperature (the average enclosure temperature in our test apparatus conforms very nicely with the return air to the air conditioner.
  • How does this process differ from those used by other manufacturers?
    Some companies define the delta T portion of the curve based on an average between the air conditioner supply air and the return air, while others use only the supply air temperature. We feel that the average enclosure temperature or return air temperature is a much better, accurate and repeatable method.
  • Why doesn’t TECA recommend or have filters?
    TECA has been building and selling standard thermoelectric air conditioners since the 1970s. In that time we have learned that, unfortunately, filters that do not get changed or cleaned with regularity breed problems. The result is a clogged filter and an overheated air conditioner. TECA units will not foul as fast nor as often as a filter.

Thermoelectric Technology:

  • Can I heat as well as cool with TECA’s thermoelectric units?
    Yes; many models have a heat option. These are designated by an HC suffix in the model number. To extend the life of the modules and to avoid the potential hazards which can result from misuse of the reverse polarity heating feature of the modules TECA often employs resistive heaters built into its heat/cool systems. Other times the reverse polarity effect is employed.
  • What are the advantages of a TECA unit over a compressor system?
    TECA units do not have any moving mechanical parts, except the fans. This makes them extremely reliable, as they do not require regular maintenance. They have a compact, simple structure and can be easily adapted and mounted to your enclosure. They do not contain any pollutants such as CFCs or other gasses.
  • What are the voltage requirements for TECA units?
    We have DC-powered units that run on 12/24/48VDC. We have AC-powered units that run on 120-240 VAC. 208 volt and 50/60/400 Hz are available as well.
  • Do any TECA units have UL, CSA, or CE approval?
    Yes, some units have been tested to UL and CSA standards by ETL labs, when appropriate, others when appropriate carry CE mark. See the UL/CSA/CE page of this site for products that meet these standards.
  • How long will a typical TECA unit last?
    The life expectancy of TECA modules is high due to the durability of solid state construction. The service life of our air conditioners is typically in excess of five years under normal conditions.

Applications:

  • Can thermoelectrics be used to cool/heat by direct contact?
    Yes, this can be done with our Cold Plate Series. We have both air-cooled and liquid-cooled versions.
  • Can TECA units be used for human comfort air conditioning?
    Yes, within limits. While one of our units would be perfect for a personal comfort item such as a cooling vest, it would take multiple units to cool residential or other larger spaces. Our largest unit is rated at 6000 BTU/hr, while a typical house requires 30,000 to 60,000 BTU/hr.
  • In what types of environments are TECA units used?
    We have units for indoor use, which are rated Nema-12. Nema-12 units are designed to protect against dust, falling dirt, and dripping, non-corrosive liquids. We also have units for indoor and outdoor use, which are rated Nema-4X. Nema-4X units are designed to protect against corrosion, windblown dust and rain, splashing water, and hose-directed water.
  • Can I use any of TECA’s units for cooling a laser?
    Yes, TECA makes a series of Liquid Chillers for these types of applications.
  • Are any TECA units explosion-proof?
    Yes. TECA’s XP Series is designed for Class 1, Division 2 hazardous environments. This series is also rated Nema-4X.
  • What do I need to know to select an air conditioner?
    You should know the maximum ambient temperature, the maximum allowable internal temperature and the total heat load.
  • Do I have to mount TECA air conditioners in a certain position?
    No, our Solid-State Air Conditioners will work in any position. Where there is a choice, side orientation is preferred by most users. Wherever the units are placed, the fans and fins need to be free of obstructions so that airflow is not impeded. Mounting upside-down is not recommended. More information about mounting.
  • Can TECA liquid chillers be used to cool potable water?
    Not directly. They can be used to chill the container in which water will be stored. The internal parts are not designed to come in contact with potable water.

Defining Terms:

  • What is “delta T”?
    “Delta T” refers to the temperature differential. We caution our customers to make sure what delta T refers to in each individual calculation. In our performance curves and equations, it can represent several things. For air-cooled air conditioners, it can indicate the temperature difference between ambient and enclosure temperatures or the temperature difference between ambient and the cold sink (cold side heat exchanger). For liquid-cooled air conditioners, it can refer to the temperature difference between cooling fluid and enclosure temperatures or the temperature difference between cooling fluid and the cold sink (cold side heat exchanger). For cold plates, it represents the temperature difference between ambient and cold plate temperature when using air cooled cold plates or the temperature difference between the cooling fluid and the cold plate.
  • What is “ambient temperature”?
    The ambient temperature is the temperature of the air surrounding the enclosure to be cooled. Typically, the room temperature.
  • What is meant by “maximum allowable internal temperature”?
    It is the highest temperature the electronics or other equipment in the enclosure can safely operate.
  • What is an “active load”?
    By “active load” we refer to the amount of heat generated within the enclosure. Typically this can be thought of as the “Volts times Amps equals Watts” type of heat generated by the electronics. In determining this value, one must be careful to calculate the amount of heat which remains in the enclosure. For example, an enclosure may contain a power supply, the relays and control system which control some function outside of the enclosure. The “active load” can be quickly estimated by measuring the “Volt times Amps” which enter and leave the enclosure. The difference can be assumed to remain in the enclosure.
  • If I can’t calculate my “active load” how can I determine it?
    If you can’t calculate it by summing the heat dissipation of the components, try subtracting the total energy leaving the enclosure from the total energy entering the enclosure, an energy balance. Another option is to remove any means of cooling the enclosure, run the components at full power and measure the delta T from enclosure to ambient and use the size of the enclosure with the TECA ® Sizing Software to “back” an answer out.
  • What is “passive load”?
    By “passive load” we refer to two types of loads: any solar or radiant load and the load through the walls of the enclosure to the delta T from ambient to enclosure. For solar loads, a good estimate is 15 watts per square foot of surface area. For the load through the enclosure walls, we recommend TECA ® Sizing Software.
  • What is total heat load?
    “Total heat load” is the total amount of heat (in watts or Btu/hr) that the air conditioner must remove. Typically this consists of the sum of the active and passive loads.
  • What is meant by “built for remote temperature control”?
    When a TECA unit is “built for remote temperature control,” it is set up to be controlled by an external yet hardwired controller. We build the relays (DC drive) into the unit and include a cable, which will provide power to the controller and to drive the relays. Units built for remote control are often used with TECA TC3300 temperature controllers.
  • What is meant by “integral controller”?
    An “integral controller” is a controller that is built into the unit.

Doing Business With TECA:

  • Does TECA build custom units?
    Yes. We are happy to work with our customers to meet their cooling/heating requirements any way that we can. Custom assemblies are a substantial part of our business. Contact us for information about custom units.
  • Does TECA have distributors?
    How can I purchase TECA products? We are a factory-direct company. Call 888-TECA-USA or (773) 342-4900 between 8:00am – 4:30pm Central Time to order.
    You can reach us 24 hours a day via fax or e-mail.
    Fax: (773) 342-0191
    Email: sales@thermoelectric.com
  • Can I place a blanket order to get a better price?
    Yes. A purchase order with total quantity and scheduled release dates would be required. Contact us for more details.
  • What are TECA’s credit terms?
    Terms of payment are Net 30 days after shipment, subject to approved credit. New accounts must furnish necessary credit references. Until credit has been established, payment in full with the order, L.O.C., or C.O.D. may be requested.
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