C terminal: Completes the circuit for continuous power, essential for smart displays and Wi-Fi modules. Power Sources and the Transformer Most residential thermostats operate on low voltage, which is supplied by a transformer located near the furnace or air handler.
Thermostat Wiring Step by Step Guide
The Basics of Thermostat Wiring Every thermostat, from basic mechanical units to advanced Wi-Fi controllers, relies on a set of terminals labeled with letters. Multi-Stage and Heat Pump Setups W1 and Y1: Primary heating and cooling stages.
O and B terminals: Control reversing valves on heat pumps, switching between heating and cooling modes. The R wire carries the positive return from the transformer, while the C wire often connects to the neutral leg to provide a steady 24-volt supply for digital thermostats.
Thermostat Wiring Step by Step Guide
Remove the thermostat cover and note the wire colors attached to each letter. Thermostat wires: Connect to the low-voltage side, with the R terminal acting as the hot side.
More About How thermostats are wired
Looking at How thermostats are wired from another angle can help expand the discussion and give readers a second clear paragraph under the same section.
More perspective on How thermostats are wired can make the topic easier to follow by connecting earlier points with a few simple takeaways.
