Indoor Thermostat
From Free Knowledge Base- The DUCK Project: information for everyone
A building thermostat is a device to control the heating and air-conditioning systems in a home, office, or other indoor environment.
The majority of modern heating/cooling/heat pump thermostats operate on 24 volts A/C.
4 Wire 24V HVAC Thermostat Wire Diagram
W : White Wire : Heat Y : Yellow or Black Wire : Cool G : Green : Fan R : Red : 24v
Jump W + R will turn on heater on a gas operated HVAC system. On the gas system the fan is triggered automatically at the heater when a certain temperature is reached.
Jump G + R to force the fan to turn on
