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Aprilaire 51

110 Volt Current Sensing Relay

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The current sensing relay senses a current in your furnace's 110 volt  fan power line by proximity. Simply run the fan wire through the top loop of the relay and when the fan turns on, the relay closes, allowing the 110 volt power on the relay side to flow through and turn on any device, such as a 110 volt humidifier, duct booster fan, etc. 

In 2002 Alpine Home Air Products became the first company to sell heating, air conditioning and indoor air-quality products online. We have proudly served hundreds of thousands of customers, helping them save time and money by buying their products direct.