Available in three sizes, the heater-cooler can fit into small- to medium-sized electrical and electronic enclosures. These are solid-state heat pumps that operate on the Peltier effect. The unit can be used to heat or cool full time. Also, with the optional temperature controller, the self-sensing system automatically activates a heating function to raise the internal temperature of the enclosure when it goes below the preset threshold, or cools the enclosure as temperatures rise above preset levels. The NEMA 4X-rated thermoelectric modules have few moving parts (only fans) and no filters to change.

Adalet, 4801 W. 150th St., Cleveland, OH 44135; 216-267-9000; www.adalet.com

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