I believe e3 is an outdoor sensor problem, most people use manual mode, you should see a blue jumper that is connected to 2 OD terminals at the control, or if u use a sensor there should be a wire run outdoors, if you dont have the manual mode part you have to get it from an aprilaire dealer, cant just jump it out, it is a resistor
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I believe e3 is an outdoor sensor problem, most people use manual mode, you should see a blue jumper that is connected to 2 OD terminals at the control, or if u use a sensor there should be a wire run outdoors, if you dont have the manual mode part you have to get it from an aprilaire dealer, cant just jump it out, it is a resistor