Here’s How to Check If Your Heater Is Working

how to check if heater is working

If you need a heating system evaluation to ensure your unit works correctly, our team at JC Heating & Cooling can help. Call today for an appointment!

When temperatures drop outdoors, you’ll likely keep your home warm and cozy with the help of a heating system like a furnace or heat pump. Unfortunately, furnace functionality can change after being off all summer long, which can leave your household feeling more of the bitter cold than you want. Yet, knowing how to check if a heater is working is the first step to troubleshooting your system. 

As a premier furnace maintenance company in La Grange, Illinois, JC Heating & Cooling and our team of certified, factory-trained technicians are well-versed in addressing the needs of all types of heating systems. If you want to perform a heater inspection before booking a professional home heating assessment, consult our guide below to learn how. 

How to Check If Your Heating System Works

The last thing you want to deal with on a freezing winter day is a furnace that won’t turn on or stay on. Though the best thing to do is contact a qualified HVAC contractor if your heating unit stops working, you might be able to uncover the cause of your problem if you know how to check if a heater is working. 

Before calling a local heating and cooling company, use these tips to learn if your heater has a simple, easily fixable problem or a major issue that requires professional help. 

Turn the Heater On

Even if it’s still warm outdoors, you should turn on your heater. Doing this step before the temperatures drop will alert you to problems that need immediate attention so you can address them before winter. 

When you turn on your heater, let it run for about 15 minutes. If nothing happens during that time, move on to the next step.

Check the Power Switch

It’s easy to turn off a furnace accidentally. Perhaps you unknowingly hit the on/off switch the last time you checked your furnace, or maybe an electrician, plumber, or another technician accidentally hit the button while working around the unit. 

If the power switch is off, that could be the reason your heating system won’t work. Turn it on and see if the furnace turns on correctly.

Look for a Tripped Circuit Breaker

The on/off switch on the heater isn’t the only way the system can lose its power. You could also have a tripped circuit breaker on your hands.

Check your electrical panel and see if the breaker switch for the heating system is off. The appliance should resume working when you flip the switch on. 

If your furnace’s breaker keeps tripping, it’s likely due to the activation of a safety feature on the heater like one of these:

  • Vent Safety Switch: Proper ventilation is necessary for ridding buildings of flue gases. The vent safety switch ensures the gases can escape from the furnace safely. 
  • Upper Limit Switch: Many furnaces have an upper limit switch or furnace safety switch to detect extreme heat inside a furnace. The system will shut down if high temperatures from a faulty blower motor, control board, or capacitor activate the switch. 
  • Flame Sensor: A flame sensor or thermocouple will turn the furnace off if it detects a weak pilot light. A thermocouple prevents explosions and fires in older furnaces, while modern equipment uses flame sensors.

Activation of these safety sensors and switches will require a system reset to ensure the furnace will resume operation. Since these sensors ensure your safety, it’s best to contact an HVAC professional to inspect your system to ensure no hazards are present. If they identify a problem, they can fix it immediately. 

Replace Your Thermostat's Batteries

Sometimes, a furnace that won’t turn on will be fully functional, but the thermostat will have a problem. Your thermostat controls your HVAC system; if the device is faulty, the furnace won’t turn on. 

Dying batteries are the most common reason for thermostat failure. Replace the batteries and ensure the thermostat’s settings are on “heat” at a higher temperature than what the device currently reads. Unless the temperature setting is higher than your home’s current temperature, the equipment won’t trigger the furnace to work. 

Change the Air Filter

Your air filter might not seem like an important component in your heating system, but it is. The filter traps airborne particles as air circulates through the furnace and your home. Over time, the screen will become dirty with dust, pollen, bacteria, and other debris, which can shed onto the furnace’s interior components. 

Too much dirt and debris in your heater can prevent it from working correctly. Ideally, you should replace disposable air filters at least once every three months. When you replace your filter, be sure to close the cover completely, or the heater might not turn on. 

How to Test a Heat Pump

When you learn how to check if a heater is working, you should remember that some systems require additional steps. For example, you’ll need to turn a heat pump to “heat” mode, turn the temperature up about three degrees, and wait a minute to see if the heat turns on.

You may need to check the condenser unit outside to ensure that the component turns on as well. Contact an HVAC contractor if you notice unusual noises or don’t feel the heat kick on. 

Trust JC Heating & Cooling for Reliable Heating Appliance Verification

Whether you know how to check if a heater is working or are unsure how to troubleshoot your furnace or heat pump, you can rely on JC Heating & Cooling. As a five-star rated HVAC company in La Grange, Illinois, offering comprehensive heating and cooling services and customized solutions, our technicians can perform a heater performance test to identify the cause of your heater’s reduced output. 

JC Heating & Cooling is here to answer questions like “How does a boiler work?” while providing outstanding services and customer care. We’re available 24/7, so call us at (708) 367-6720 for an appointment.