Smart Thermostat vs. Programmable Thermostat: What’s the Difference?

Quick answer: A programmable thermostat follows a schedule you set at the wall. A smart thermostat adds Wi-Fi for phone control, and many models learn your routine, notice when nobody is home and report how long your system runs. Either one saves energy only if its schedule matches how you live.

What does a programmable thermostat do?

It changes the temperature on a timetable. You might set a warmer cooling setpoint (the temperature you pick) for weekday work hours and a comfortable one for evenings, and it switches on its own. Most models allow separate weekday and weekend schedules. With no internet connection, every change happens on the buttons or touchscreen at the wall.

The weak spot is people. Plenty of programmable thermostats spend their whole lives on “hold”, a fixed temperature that ignores the schedule, either because nobody set the schedule or because it stopped matching the household two jobs ago.

What can a smart thermostat do that a programmable one can’t?

It connects to Wi-Fi, so you can run it from your phone, and it can automate the schedule. ENERGY STAR lists the common features:

• Remote control from your phone, anywhere you have internet.
• Geofencing, which uses your phone’s location to tell when you’ve left or are heading home.
• Learning, which picks up your preferred temperatures and builds a schedule for you.
• Reporting on how long the system runs, plus software updates over the air.

Some models also accept remote room sensors, send filter reminders and flag unusual temperatures. That last one earns its keep when you’re out of town during a July heat wave or a January freeze.

Does a smart thermostat save more energy?

Not automatically. The thermostat that saves more is the one whose schedule you actually use. A well-programmed thermostat can do the job. A smart thermostat’s edge is that it keeps working when your routine changes.

Smart thermostats that earn the ENERGY STAR label are certified on savings measured in real homes. In Austin, the biggest lever is the cooling setpoint while the house is empty, covered in what to set your thermostat to when you’re away.

What kind of thermostat does a heat pump need?

Ideally one built for heat pumps. The Department of Energy cautions against deep temperature setbacks on a heat pump (big drops while you’re out or asleep) unless the thermostat is built for heat pumps. When a basic thermostat asks for a big jump in the morning, it can call in the electric heat strips, the heat pump’s costly backup.

A heat pump model brings the temperature back gradually instead. Aux heat vs. emergency heat explains what those strips are doing.

Should you get a smart or programmable thermostat?

It depends on your routine and your equipment:

• Programmable suits a steady schedule, no need for phone control and a taste for simple.
• Smart suits irregular hours, frequent travel, an interest in usage data or a utility thermostat program.
• The maker’s own control may be required to run every feature of a two-stage or variable-speed system, one that can run at more than one speed.

Most smart thermostats also need a C-wire (a constant 24-volt power wire), which some older homes lack. Check before you buy, as covered in whether a smart thermostat is worth it. Gold Eagle installs and sets up thermostats.

What should you do next?

• Check whether your thermostat is actually running a schedule or sitting on “hold”.
• Set a warmer cooling setpoint for the hours the house is empty.
• Keep setbacks modest on a heat pump, or use a heat pump model.
• Confirm which control the equipment maker requires before buying for a two-stage or variable-speed system, or ask Gold Eagle.

Related guides: Smart Thermostats: Are They Worth It?, What Should You Set Your Thermostat to When You’re Away? and Aux Heat vs. Emergency Heat: What Your Heat Pump Thermostat Is Telling You.

About Gold Eagle Services: This guide comes from the team at Gold Eagle Services, a family-run Austin HVAC, indoor air quality and mold remediation company founded in 2017. We’re licensed (TACLA119235 and RCO1783), insured and bonded, and we serve homes across the greater Austin area.

Need help with this in your home? Learn about our air conditioning repair and installation, or call 512-489-4653 to schedule a visit.

Related Gold Eagle service: AC repair in Austin