When does the thermostat send a 12VDC signal?
When does the thermostat send a 12VDC signal? When the need for Cooling or Heating exists the thermostat sends a 12VDC(+) signal to the control relays or a P.C. board which in turn energizes the air conditioner components or the furnace. (Note: Relays and P.C. boards will be further discussed later in lesson II). What causes a fuse to blow in a house? Fuse panels haven’t been installed in homes for several decades; their technology lacks most of the safety features of modern circuit breakers. Any faulty wiring or connected parts risk a power fault (surge), which trips a circuit...