What to Do if Your Heater Won’t Turn On

There’s nothing worse than turning on your heater on a chilly day only to find that it won’t start. Whether you rely on a gas furnace, an electric heater, or a heat pump, a heater that won’t turn on can leave you feeling frustrated and uncomfortable. Before you start worrying about costly repairs, there are a few common issues that you can check yourself. However, if troubleshooting doesn’t resolve the problem, it’s best to call an expert like Stone Heating and Air to diagnose and fix the issue. Here are some of the most common reasons why a heater won’t turn on, what steps you can take to troubleshoot the problem, and when it’s time to call a professional.

Common Reasons Your Heater Won’t Turn On

Several factors can prevent your heating system from starting up properly. Understanding the root cause can help determine whether you can resolve the issue yourself or if professional help is needed.

1. Thermostat Issues

One of the most common reasons a heater won’t turn on is a problem with the thermostat. If the thermostat isn’t functioning properly, it won’t signal the heating system to start.

How to check it:

• Make sure the thermostat is set to “HEAT” mode.
• Increase the temperature setting by a few degrees to see if the system responds.
• Replace the thermostat batteries if it’s a battery-operated unit.
• If your thermostat is programmable or smart, check for software issues or settings that may have disabled heating.

2. Power Supply Problems

Even gas-powered heaters rely on electricity to operate components like the thermostat, igniter, and blower fan. A tripped breaker, a blown fuse, or an unplugged power cord could be to blame.

How to check it:

• Check your home’s electrical panel for tripped breakers. If the heater’s breaker has tripped, reset it and see if the system turns on.
• If your heater has an on/off switch, make sure it’s turned on.
• Ensure the unit is plugged in if it’s an electric heater.

3. Pilot Light or Ignition Failure

For gas furnaces, a pilot light or electronic ignition failure can prevent the unit from heating your home. A dirty or faulty igniter may require cleaning or replacement.

How to check it:

• If you have a gas furnace with a standing pilot light, check if it’s lit. If not, follow the manufacturer’s instructions to relight it.
• If you have an electronic ignition system, listen for a clicking sound when the furnace attempts to ignite. If there’s no clicking sound, the igniter may be faulty.

4. Clogged Air Filter

A dirty air filter can restrict airflow, causing the system to overheat and shut down for safety reasons. If airflow is blocked, the heater may not turn on or function efficiently.

How to check it:

• Locate the air filter and check for dust and debris. A dirty filter can block airflow and shut down the system.
• If the filter is dirty, replace it with a clean one.
• Regularly changing your air filter can prevent future issues and improve efficiency.

5. Gas Supply Issues

If you have a gas furnace, make sure the gas valve is open and that there are no gas supply issues in your home. A disruption in the gas line will prevent the heater from working.

How to check it:

• Make sure the gas valve leading to the furnace is fully open.
• If you suspect a gas supply issue, contact your gas company. If you smell gas, leave your home immediately and call emergency services.

6. Blocked or Closed Vents

Blocked or closed vents can disrupt airflow, making it difficult for the system to operate properly. Make sure all vents are open and unblocked.

How to check it:

• Ensure all vents are open and unobstructed.
• If you have a central heating system, make sure no furniture, rugs, or objects are blocking airflow from vents.

7. Faulty Limit Switch or Blower Motor

If the blower motor or limit switch is faulty, the heater may not run even if everything else is functioning properly. These components typically require professional attention.

When to Call Stone Heating and Air

If your heater isn’t working and troubleshooting hasn’t solved the problem, don’t wait until the temperatures drop further—call Stone Heating and Air for expert assistance. As a Carrier Factory Authorized Dealer, we offer top-quality service and access to industry-leading Carrier heating systems, ensuring your home stays warm and energy-efficient all season long. Our experienced technicians can quickly diagnose and fix heating system issues to restore comfort to your home. Here are a few scenarios where expert help is necessary:

1. Your Furnace Won’t Ignite or Stay Lit

If your furnace’s pilot light won’t stay lit or the electronic ignition system fails, a professional technician can safely diagnose and fix the issue.

2. Unusual Noises or Odors

Loud banging, screeching, or rattling noises coming from your heater could indicate a mechanical problem. Similarly, strange odors (like burning plastic or rotten eggs) may signal serious issues that require immediate attention.

3. Repeated Circuit Breaker Trips

If your heater keeps tripping the breaker, it could be due to an electrical problem that needs professional repair. Continuing to reset the breaker without addressing the issue can be dangerous.

4. Your System Short Cycles

If your heating system turns on and off frequently without reaching the desired temperature, it could be due to an overheating issue, faulty sensor, or airflow problem. A technician can diagnose and resolve the problem.

5. Your Heater Runs But Doesn’t Heat Your Home

If your heater is running but not producing warm air, there may be an issue with the blower motor, gas supply, or heating elements.

6. You Haven’t Had a Tune-Up in a While

Regular maintenance is essential for keeping your heater running efficiently. If it’s been a year or more since your last professional HVAC tune-up, scheduling a service appointment can prevent unexpected breakdowns.

Whether you need a repair, a system tune-up, or a full replacement, our experienced technicians are here to provide reliable solutions tailored to your needs. Contact Stone Heating and Air today to schedule a service appointment and experience the comfort and reliability of Carrier heating products backed by professional, customer-focused service.

Don’t let a faulty heater leave you in the cold! Contact Stone Heating and Air today to schedule a service appointment and get your heating system back up and running.