Why would the furnace fan be tied to my master bath fan?
My furnace fan comes on with the fan in my master bath. And the vent fan when the furnace operates. Why would the furnace fan be tied to my master bath fan? I also see that the fan draws air from an outside vent. We have a smell coming out of our vents that smells like rotten hay. Never seen a setup like this. Not sure what to do...