<B>Aprilaire 4851 Blower Activation Relay for 500, 600 & 700 Series Humidifiers (Automatic Control) Review</b><P>http://tinyurl.com/mpzpa5t <P><P> Aprilaire 4851 Blower Activation Relay for 500, 600 & 700 Series Humidifiers (Automatic Control) <P>Aprilaire #4851 Blower Activation Relay.<P>For Aprilaire series 500, 600, and 700 humidifiers that use the Automatic Digital Humidifier Controls (# 56 and # 58).<P>Allows digital control (#58) to turn on system fan when there is a call for humidification (but not heat).<P>This device will initiate HVAC fan operation when there is a call for humidity, even when there is no heat call.<P>
