Thermostat communication has evolved substantially in recent years. For decades, the basic communication between thermostat and HVAC components was a simple four-wire system: power, furnace, AC, and fan. The simple concept provided on/off operation of the furnace and air conditioner based on an electromechanical switch that sensed temperature in a single room. As digital programmable thermostats came along, however, the wires became more numerous and the functions more complex in order to add automation and enhanced monitoring to your HVAC system. 

Today’s advanced smart thermostats are basically small computers that mount on your wall. In addition to a multiplicity of additional features, these new units may also include thermostat communication technology that frees the system from the limits of wired operation while expanding system control and monitoring functions.

Some basic features of these systems include:  

• The main thermostat typically wirelessly connects with the home router and communicates with HVAC components via Wi-Fi.  
• In most cases, components in these systems are made by the major manufacturer of the air conditioner or furnace or by a third-party such as Nest.
• These systems may incorporate multiple temperature-monitoring sensors throughout the house in order to fine-tune temperature adjustments.
• Communicating thermostats are increasingly common in homes with variable-speed HVAC components. In this application, the system not only monitors and adjusts temperature but also supports control of airflow volume throughout the house.  
• In addition to operating the air conditioner and furnace, depending on the brand, these thermostats may communicate with and control other HVAC devices, including whole-house dehumidifiers and air purifiers, as well as home devices such as lighting and security systems.
• All control functions of the HVAC system, as well as extensive monitoring of indoor conditions, are accessible remotely by smartphone or tablet with a dedicated app.

For more information about the latest technology in thermostat communication, talk to the HVAC professionals at Powers Heating & Air.