Ways to Check If Your Thermostat Has Gone Bad

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woman checking thermostat for problems

If the thermostat in your home is failing, you need to get it fixed right away. This is not the kind of issue that you can safely ignore. Failing to get your thermostat fixed can lead to major expenditures of time, energy, and money. If you suspect something is wrong, the time to address the issue is now. A faulty thermostat in the Arizona summer heat can be a costly problem.

Troubleshooting and Testing Steps

woman checking thermostat for problemsWith any air conditioning problem, you want to troubleshoot following a few steps. There are a number of steps that you can use to test and troubleshoot your thermostat. These include the following:

Check the Thermostat Temperature

The first thing you need to do is check the temperature of your thermostat. Do this by checking the set point of your thermostat against the temperature in the room. The set point on your thermostat is the temperature you desire it to remain at. Your heater should only be running when your set point is above the temperature in the room.

Check the Connections on Your Thermostat

The next thing you will need to do is check the connections on your thermostat. You can take off the cover in order to expose the wire connections. The most common ones will be R for 24-volt power, W for heat, Y for cooling, G for your fan, and C for the common side of the 24 volts.

If there is no wire connection to C, this means that your thermostat is battery powered. Depending on how it is set, R will internally connect to W, Y, or G. This is to order the corresponding equipment to turn on. You need to be sure that all of these connections are tight and have firm contact.

Make Sure Your Thermostat Isn’t the Problem

Shut off the power to your furnace. Once the power is off, remove the wires from the thermostat and carefully label them. Twist the R and W wire ends together. Turn the power back on. At this point, the furnace should come on.

Check R to Y and R to G. Make sure that your cooling system and fan turn on. If all your equipment turns on when the wiring is correct but wasn’t when you had it directly hooked up to the thermostat, this is proof that your thermostat is faulty.

Problems Caused by a Bad Thermostat

There are a number of very serious problems and symptoms that can be caused by a bad thermostat. These can include, but will not be limited to the following:

Short Cycling

Short cycling can happen when your heater shuts down before completing its regular cycle. If this happens too often, it can lead to extreme wear and tear as well as rapid aging. This will entail multiple repair jobs as well as an eventual early replacement.

There are a number of reasons why your heater may begin to short cycle. One of the most common causes is a thermostat that becomes mis-calibrated. If this occurs, it will begin to sense temperatures incorrectly. This will lead to short cycling.

Blower Won’t Stop Running

Another major cause of trouble occurs when your blower is unable to stop running. Your thermostat uses a series of separate wires to turn your blower motor on and off. If it suddenly loses a connection to one of these wires, it could cause the motor to turn on and keep running with no ability to stop.

The only way to force a stop in this case will be to disconnect the entire system from the power source. This is not advisable because it wastes energy. Doing this too often will cause rapid wear and tear on the motor.

Air Conditioner Refuses to Turn On

There is also a set of wires on your thermostat that are intended to send the signals to your air conditioning and heater to turn on and off. If one of these wires is frayed or damaged, it could lead to your AC or heating being unable to turn on at all. This can be one of the most irritating and confusing of the many issues that a thermostat malfunction can lead to. The problem might seem to point to a full system breakdown when, in reality, it may only call for a minor thermostat repair.

Additional Symptoms You May Experience:

  • Furnace clicks but doesn’t turn on
  • Thermostat not cooling
  • Thermostat won’t change temperature

What is the Average Cost to Replace a Thermostat?

Nest Pro Smart ThermostatThe average cost to replace a thermostat in Phoenix or the surrounding area will run anywhere from about $260 to $311. A number of factors will play into this equation. There is the cost of the thermostat itself as well as whether you supply this part or depend on a professional service to locate it for you.

There are also other factors to consider. These may include the length of time it takes to do the job, as well as the cost of disposing safely of the unit once it has been removed. Talk to us today to get a preliminary estimate of the total cost of your repair so that there will be no surprises when the bill comes due. We carry many of the best brands of thermostats like: Honeywell, Carrier, Emerson and Nest Smart Thermostats. Many of the replacement thermostats we use now help with energy efficiency, are touch screen and can connect to your smart phone.

Contact the Phoenix AC & Heating Experts for More Info

If your home thermostat has malfunctioned, you have options. Your best bet will be to contact the Phoenix AC & Heating Experts to get your thermostat replaced. We have the knowledge, skills, and experience to do the job quickly and for a price you can easily afford. Get in touch with us today to learn more.