How To Reset An AC Thermostat?



air conditioning service repair

When your home air conditioner stops working in Phoenix, AZ it becomes an instant emergency. We have reason for concern without a working AC unit here in the Valley. Especially on hot summer days like this week’s 115° temperatures forecasted. Not all AC repairs are major however, so there are a few things you can check before scheduling AC repair. Let’s start by answering the title question, How To Reset An AC Thermostat?


Resetting a Non-Working AC Thermostat

There are many different types of thermostat on the market today, so knowing what you have is step one.

  • Is your thermostat analog or digital?
  • Does your thermostat require batteries in order to maintain a program?
  • Are you dealing with a manufacturer proprietary “communicating” thermostat or is it universal?

These are some of the questions you need to answer in order to determine if your thermostat can be reset. Let’s look at them one by one so you know what you’re dealing with.

Is your thermostat analog or digital? This one is pretty easy. If your thermostat has a display with digital numbers instead of printed numbers on a dial – it’s digital. If it has printed numbers and you have to turn a dial or slide a lever – it’s analog.


Answer these three questions and follow the instructions to reset your air conditioner’s thermostat.


Question 1: Do you have a digital thermostat?

NO > There is no “reset” for analog thermostats. Continue to the step by step instructions below to reset your AC unit.

YES > Continue to question 2.


Question 2: Does your AC thermostat require batteries?

thermostat settings

NO > Continue to question 3.

YES > Step 1: Replace batteries.

Note: Use regular alkaline batteries only, most use either AA or AAA batteries.

Step 2: Did your ac thermostat reset?

NO > Continue to question 3.

YES > Unless there is another problem with your air conditioning & heating system your unit should begin operating normally.

NOTE: You may have to reenter your preferred schedule/program. Refer to manufacturer programming instructions.



Question 3: Do you have a “communicating” proprietary manufacturers thermostat?

NO > Continue to the instructions below.

YES / UNSURE > Most HVAC (Heating, Ventilation, & Air Conditioning) equipment manufacturers are moving to proprietary thermostats that “communicate” running conditions and error codes between the thermostat, condenser, and air handler or furnace. Unlike older thermostats which are merely a fancy “on/off switch”; communicating thermostats are complex & maintain helpful information for service technicians. Do not reset your AC thermostat if it is communicating – call for professional service. This information helps the service technician determine what the fault code is. Resetting the AC thermostat before repairing the issues that caused the unit to stop working can damage your air conditioner.


Step by Step Instructions to Reset Your AC Thermostat

  • Locate your homes main circuit breaker panel.
  • Locate the circuit breaker identified as outdoor unit or condenser. Turn it off.
  • Locate the circuit breaker identified as air handler or furnace. Turn it off.
  • Switch on the circuit breaker for the outdoor unit.
  • Switch on the circuit breaker for the indoor unit.
  • Check your thermostat and determine if these steps reset it to full functionality.



Did These Steps Reset Your Thermostat? Is Your Air Conditioner Cooling Again?

NO > Unfortunately, either your thermostat is faulty and needs to be replaced, or there is another problem with your HVAC system. Contact your local air conditioning service company & schedule professional diagnosis and repair.

YES > If everything appears to be okay for a few hours your problem is most likely solved. Pay attention to unusual noises, smells, and running conditions of your AC & heating system. If anything doesn’t “feel right”, you should schedule professional AC service.


Did you like How To Reset An AC Thermostat? You may also like:

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If you live within 35-miles of Mesa, AZ., Magic Touch Mechanical provides 5-Star Air Conditioning Service, Repairs, Maintenance, & Installation in your neighborhood! Contact us today to schedule service we guarantee you’ll love!

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