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Locate the battery compartment (found at the rear of the thermostat, on the circuit board). Install two AA size alkaline batteries (either Energizer or DURACELL brand) into the compartment. Ensure that the batteries are installed correctly using the polarity markings on the compartment
Read more: Lux TX1500 Instructions | eHow.com http://www.ehow.com/how_8452877_lux-tx1500-instructions.html#ixzz1l0A8Tls7
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