An air-treatment system comprises an air-intake chamber in fluid-flow communication with an air-treatment chamber and an air-exhaust chamber in fluid-flow communication with said air-treatment chamber. The air-intake chamber has an air-intake port placing said air-intake chamber in fluid-flow communication with an environment exteriorly of said air-intake chamber, said air-treatment chamber, and said air-exhaust chamber. The air-exhaust chamber has an exhaust-air port placing said air-exhaust chamber in fluid-flow communication with the environment exteriorly of said air-intake chamber, said air-treatment chamber, and said air-exhaust chamber. A canister assembly removably disposed within said air-intake chamber comprises a plurality of heat-conductable canisters each adapted for containing a heat-exchange substance. The canisters are disposed in spaced-apart arrangement permitting air flow between and around the canisters. A fan is disposed for drawing in air through said air-intake port, circulating said air between and around said canisters and exhausting said air through said exhaust-air port.